56 replies to this topic

[cheapracer]

Here's some nice light reading if you have a moment ....

http://www.hotrodder...tch-built/Cover

[Lee Nicolle]

Here's some nice light reading if you have a moment ....

http://www.hotrodder...tch-built/Cover

Some of that scares me, and some is a good idea.
But why use a big heavy I beam at all. A fad rod will always be a traditional beam. and drive bloody awful.
And a full fenderes car can use a modern double wishbone front suspension. generally from a ute these days and get softer coils wound to suit the weight of the car.
And there is so many fabricated suspension kits around these days to build your own, most sem ok though it is suck it and see i they work properly.

as a complete aside. My 40 year old Super modified has always been a slipper spring on the right side. metal against metal. I had a nylon sleeve made that fits on the slide. The car feels better, rides better and adjusts better because of the lack of friction.A friend had some made for his slipper spring car trailer and it rides nicer empty and with light loads as the spring is sliding instead of frozen against the chassis.
The roller bearing set up would be even better but takes too much away from originality.
The roller bearing set up you can buy from several suppliers. Straight out of the AFCO catalogue. A lot of speedway sedans use it on the rear springs.
The AFCO catalogue can be downloaded off the net.There is a lot of innovative ideas advailable to be bought.
Though really all suited for race use not road cars!

[johnny yuma]

Ground clearance in middle of front looks a problem.A high crown would turn it into a nice grader or scraper.

[Lee Nicolle]

Ground clearance in middle of front looks a problem.A high crown would turn it into a nice grader or scraper.

Drop axle hot rods have done that for years. You are very selective where you drive those things.

[Todd]

Why did Ford redesign their swing axle front end in 1980 to have one long and one short axle? Insane.

[Lee Nicolle]

Why did Ford redesign their swing axle front end in 1980 to have one long and one short axle? Insane.

I agree, you would think that it would generate heaps of bump steer, and weird handling in general. But they actually drive well for a commercial vehicle. But to me still far too heavy for a hotrod.
Still the worlds manufacturers all produce cars and commercials that are inherently unstabe and unsafe,,,, Front wheel drive, though most drive ok. But engineering to make a bad design good or a good design better. Hmmmm lets see!

[bigleagueslider]

Classic American hot rods are more about style than handling. Think about an open T-bucket rod, with a 600HP blown small block, 16 inch wide tires in the back, and a drop axel with spoke wheels and narrow motorcycle tires on the front. There are lots of them. This rod can easily lift the front end, and there is nothing to keep the occupants from having their heads crushed when it goes end-over.



At that point, the handling qualities of the front suspension are not so critical.

[gruntguru]

In fact I can't think of anything that might matter much while your head is being crushed.

[Tony Matthews]

Apart from whether you are wearing clean underwear.

[gruntguru]

(You would be crazy to drive one of those things wearing dirty underwear.)

[Lee Nicolle]

Classic American hot rods are more about style than handling. Think about an open T-bucket rod, with a 600HP blown small block, 16 inch wide tires in the back, and a drop axel with spoke wheels and narrow motorcycle tires on the front. There are lots of them. This rod can easily lift the front end, and there is nothing to keep the occupants from having their heads crushed when it goes end-over.



At that point, the handling qualities of the front suspension are not so critical.

Hoo boy, that is an accident waiting to happen. Motorcycle wheels and NO FRONT BRAKES. Hot Rod clubs stamped that rubbish out here 30 years ago.
Apart from the total lack of steering both rims and tyres are grossly overloaded.
And no road authority would ever pass that for registration,,, EVER.
While a fad bucket will always be a very average thing with beam axles and fat skinny tyres that car is just plain moronic. And no acing organisation would accept it either.
Back in the dim dark ages when some dragsters had motorcycle wheels on the front at least they never had all that weight hanging over the tyres because of the length of the chassis.

As an aside here in Adelaide there is a very nice 68 or so Caddy doing the cruises, but it has 20" wire wheels. A US fad. All the wheels wobble and it tram tracks and bump steers everywhere. Not quite as dangerous but nearly

[Magoo]

Why did Ford redesign their swing axle front end in 1980 to have one long and one short axle? Insane.

To provide commonality with the Dana TTB front axle used on the 4WD versions. It's not as odd as it looks.

Why anyone would use Ford truck twin I-beam front end on a street rod is what makes no sense to me. It's heavy, bulky, ugly, and hilariously overbuilt the application. The split-beam or swing axle concept is ok enough but the components are way out of scale.

[Magoo]

Hoo boy, that is an accident waiting to happen. Motorcycle wheels and NO FRONT BRAKES. Hot Rod clubs stamped that rubbish out here 30 years ago.
Apart from the total lack of steering both rims and tyres are grossly overloaded.
And no road authority would ever pass that for registration,,, EVER.
While a fad bucket will always be a very average thing with beam axles and fat skinny tyres that car is just plain moronic. And no acing organisation would accept it either.
Back in the dim dark ages when some dragsters had motorcycle wheels on the front at least they never had all that weight hanging over the tyres because of the length of the chassis.

Agreed. The car shown here is more of a garage queen. I'm sure no one was more disappointed than the owner the first time he tried to actually drive it. Even the more conservative Fad Ts are severe compromises on the road.

[Todd]

That T-bucket is perfectly street legal provided it is titled as a 1923 Ford. It meets all existing safety standards of its year of construction.

[Tony Matthews]

It meets all existing safety standards of its year of construction.

[cheapracer]

Why anyone would use Ford truck twin I-beam front end on a street rod is what makes no sense to me.

Ahh just a bit of fun, looks ok to me.

Wow, great story here Guys on the "Norman Timbs Buick Special, I can barely believe it's a 1950's car! ...

http://www.kustomram...;_Buick_Special

[Tony Matthews]

Terrific! Other shots make it look slightly better balanced, I think, as the top-lighting makes the rear wing/fender look slightly odd.

[cheapracer]

I just can't believe it ended up being discarded as it was before being found and restored (thank goodness it was), based on it's age its one of the most outstanding cars I have ever seen.

[Tony Matthews]

I am looking forward to being found and restored...

[cheapracer]

I am looking forward to being found and restored...

Yes, was found in 2002 and the restoration result is the picture above.

[kikiturbo2]

I am looking forward to being found and restored...

[Magoo]

Many of these handbuilt specials exist today in far better condition than when they were new. A good number of them were never fully completed the first time around. I don't know about the Timms Buick specifically, but I have my doubts it was ever that nice. If you look at the period photos, err...

[cheapracer]

Many of these handbuilt specials exist today in far better condition than when they were new. I don't know about the Timms Buick specifically, but I have my doubts it was ever that nice. If you look at the period photos, err...

Of course but that's the same for all of them, paint being the biggest step forward - I don't remember race cars I saw in the 60's ever being shiny (like todays shiny).

And as my Dad often said to us kids near the car; "Watch the Duco....!"

[Lee Nicolle]

Many of these handbuilt specials exist today in far better condition than when they were new. A good number of them were never fully completed the first time around. I don't know about the Timms Buick specifically, but I have my doubts it was ever that nice. If you look at the period photos, err...

In those period pics that car did look very good. The 2009 shots depend on lighting. The arty shot it looks more burgundy than deep metallic red.
2 pack paint ofcourse will give a shinier finish. While not my sort of car I can well appreciate the work that went into it. Though using a Buick straight 8 is a little puzzling with the engine back that far surely a V8 would have been a better fit.Shorter and lower. Since it used a lot of Merc stuff why not the engine too. And there would have been some OHV engines around by then too.

[Kelpiecross]

In those period pics that car did look very good. The 2009 shots depend on lighting. The arty shot it looks more burgundy than deep metallic red.
2 pack paint ofcourse will give a shinier finish. While not my sort of car I can well appreciate the work that went into it. Though using a Buick straight 8 is a little puzzling with the engine back that far surely a V8 would have been a better fit.Shorter and lower. Since it used a lot of Merc stuff why not the engine too. And there would have been some OHV engines around by then too.

I hate to appear ignorant but which pctures are being discussed here? Which car with a Buick straight 8?

[desmo]

In the link cheapy posted.

Ahh just a bit of fun, looks ok to me.

Wow, great story here Guys on the "Norman Timbs Buick Special, I can barely believe it's a 1950's car! ...

http://www.kustomram...;_Buick_Special

[Kelpiecross]

[quote name='desmo' date='Aug 3 2011, 14:46' post='5215213']
In the link cheapy posted.
Thank you Desmo.

[johnny yuma]

In those period pics that car did look very good. The 2009 shots depend on lighting. The arty shot it looks more burgundy than deep metallic red.
2 pack paint ofcourse will give a shinier finish. While not my sort of car I can well appreciate the work that went into it. Though using a Buick straight 8 is a little puzzling with the engine back that far surely a V8 would have been a better fit.Shorter and lower. Since it used a lot of Merc stuff why not the engine too. And there would have been some OHV engines around by then too.

The styling/architecture may have accommodated a long narrow tall engine better than a V8. Of course the Buick was an itself an OHV of 300ci or thereabouts,but in 1948/49 when the car was being built,the only OHV V8 to my knowledge in USA mass production was the Oldsmobile Rocket 88,a bulky heavy engine and maybe unobtainable at design stage. The Buick motor looks to be the twin carb factory job..in a car weighing only 2500 lbs it would have gone all right--better than a stock sidevalve V8 of the day.

[Lee Nicolle]

The styling/architecture may have accommodated a long narrow tall engine better than a V8. Of course the Buick was an itself an OHV of 300ci or thereabouts,but in 1948/49 when the car was being built,the only OHV V8 to my knowledge in USA mass production was the Oldsmobile Rocket 88,a bulky heavy engine and maybe unobtainable at design stage. The Buick motor looks to be the twin carb factory job..in a car weighing only 2500 lbs it would have gone all right--better than a stock sidevalve V8 of the day.

Nothing against the Buick, they were a good engine in the day. But they are big long tall heavy lump. I helped pull one out in the dim past, it was about twice is big as a grey Holden. Wheras the Ford is a short, low heavy lump!!

[Magoo]

I think the choice of the Buick 8 comes down to: The guy must have liked Buicks. We see that all the time here and elsewhere in the way people plan their projects. Guys select a particular engine or combo not because it is optimal for the project, but because they have developed some affinity or affection for it. The difficulty posed by the choice may even be part of the appeal, a special challenge. In the words of my buddy Ken (Posies) Fenical, "Anyone can restore a car. It takes a real man to cut one up."

[cheapracer]

I think the choice of the Buick 8 comes down to: The guy must have liked Buicks.

It really is that simple.

[fredeuce]

A fad rod will always be a traditional beam. and drive bloody awful.

They don't alway have to drive bloody awful Lee. Those early Ford front ends were quite effective in their day and still are if set up correctly.

The problem that arises when people modify them is that it usually involves putting wheels on them that are not suited to the design. In particular looking at the twin I beam set-up as depicted in fig.3-3those wheels are all wrong . Have a look at where the king pin is located. A small diameter wheel with wide low profile tyre results in a significant scrub radius. That means as I'm sure you're aware that those fat tyres at the outer shoulder act like big levers and will pull you around all over the place dictated by terrain and road contour. Often this leads to constructors compensating for this by cranking in a good deal of caster to try to give it straight line stability. That translates to heavy steering , particularly in tight situations like car parks. This Twin I - beam installation has little caster at all. I can't imagine this would be very stable on the road.

I went through this experience myself with the low profile wider tyres on an early ford beam axle. I was glad to see the end of those tyres . I went from a 195/60/15 to a 185/80/15 tyre and problem solved.

As for the eliptic leaf spring they always need some assistance to prevent them from binding. I found that using the teflon works to a degree but it does hammer out over time. I took the strips out of mine and simply dressed the edges to avoid the ends digging to the leaves below and the placed a needle roller under the tip. The whole spring is assembled with a liberal dose of grease between the leaves . Once that was done I installed shrink tube from adjacent to the spring eye up to the centre with a space in the middle to allow the spring to seat up into the crossmember. This kept the road grime out and prevents the greas from drying out.

Once I had these improvements in place my rod would drive on open roads and off road with ease and stability. You could drive it easily with one hand on the wheel negotiate any bumps and dips and always keeps true. The spring works well and improved the ride considerably. The faster you go in it the better it gets. It is interesting to see that Sprint Cars today still run a beam axles!

[Lee Nicolle]

They don't alway have to drive bloody awful Lee. Those early Ford front ends were quite effective in their day and still are if set up correctly.

The problem that arises when people modify them is that it usually involves putting wheels on them that are not suited to the design. In particular looking at the twin I beam set-up as depicted in fig.3-3those wheels are all wrong . Have a look at where the king pin is located. A small diameter wheel with wide low profile tyre results in a significant scrub radius. That means as I'm sure you're aware that those fat tyres at the outer shoulder act like big levers and will pull you around all over the place dictated by terrain and road contour. Often this leads to constructors compensating for this by cranking in a good deal of caster to try to give it straight line stability. That translates to heavy steering , particularly in tight situations like car parks. This Twin I - beam installation has little caster at all. I can't imagine this would be very stable on the road.

I went through this experience myself with the low profile wider tyres on an early ford beam axle. I was glad to see the end of those tyres . I went from a 195/60/15 to a 185/80/15 tyre and problem solved.

As for the eliptic leaf spring they always need some assistance to prevent them from binding. I found that using the teflon works to a degree but it does hammer out over time. I took the strips out of mine and simply dressed the edges to avoid the ends digging to the leaves below and the placed a needle roller under the tip. The whole spring is assembled with a liberal dose of grease between the leaves . Once that was done I installed shrink tube from adjacent to the spring eye up to the centre with a space in the middle to allow the spring to seat up into the crossmember. This kept the road grime out and prevents the greas from drying out.

Once I had these improvements in place my rod would drive on open roads and off road with ease and stability. You could drive it easily with one hand on the wheel negotiate any bumps and dips and always keeps true. The spring works well and improved the ride considerably. The faster you go in it the better it gets. It is interesting to see that Sprint Cars today still run a beam axles!

When i was referring to fad buckets I meant beam axles, And nothing terribly wrong with them either when they are not all bound up which 99% of them are with two radius rods on either side. And semi compliant bushings that effectivly use the front axles as a VERY stiff sway bar.The original A model set up is better.Transverse is fine, in fact good on a bucket if the axle is not bound up as I said and the spring is free to move properly. A lot are not. Tapered leaves are a treat. 95E Anglia. Lubrication as you said helps but has to be done fairly regularly and shrinkwrapping the spring is ugly.But effective. But for Christ sake never chrome a leaf spring as the one above.
Coilovers on a beam is ok, but shock mounting points are critical. Cross bar sprintcar style I reckon would work great on a rod too. Though not real pretty or traditional

Sprinters, Midgets, Dirt Modifieds, F500 and no end of similar classes still use beam axles as it is in there rules, as is torque tubes.They are effective and tough but could and should be better. And some of them are bound up too. After 60 odd years you think they would get it right.

[cheapracer]

When i was referring to fad buckets I meant beam axles, And nothing terribly wrong with them either when they are not all bound up which 99% of them are with two radius rods on either side. And semi compliant bushings that effectivly use the front axles as a VERY stiff sway bar.

Sprinters, Midgets, Dirt Modifieds, F500 and no end of similar classes still use beam axles as it is in there rules, as is torque tubes.They are effective and tough but could and should be better. And some of them are bound up too. After 60 odd years you think they would get it right.

That's simply not true, as long as the radius rods run parallel and of equal chord length parallel to the vehicle's centerline then there is no binding at all - nil, zilch, none.

For a while Sprintcars, SuperModifies etc were free class and still the beam was superior even against full ground effect F1 copies (even 4WD's). As the beam still ruled on top, was used by the majority and was also the cheapest, the rule came in much later for safety as wishbones and outside walls don't mix well tending to seperate from the car and ending up on the track or in other cars and drivers.

Edited by cheapracer, 05 August 2011 - 10:49.

[Lee Nicolle]

That's simply not true, as long as the radius rods run parallel and of equal chord length parallel to the vehicle's centerline then there is no binding at all - nil, zilch, none.

For a while Sprintcars, SuperModifies etc were free class and still the beam was superior even against full ground effect F1 copies (even 4WD's). As the beam still ruled on top, was used by the majority and was also the cheapest, the rule came in much later for safety as wishbones and outside walls don't mix well tending to seperate from the car and ending up on the track or in other cars and drivers.

Cheapy, believe me they are bound up.If you use 2 lower links and 1 top one the car rolls. Use 2 top links and the car lifts inside wheels. That is why manufacturers all use big gooey soft bushes on 4 link rear cars. Sprinters largely alleviate bind as the hub carriers are where the suspension is mounted too. But the torque tube is a huge bind in itself, and they break regularly, and pull the bolts out of the diff in accidents. most doffs these days have two sets of holes for that reason. And the real reason for torque tubes? Because quick changes are based on a early Ford V8 set up, which as we know were torque tube. Early sprintcar Halibrands etc and some midget diffs still use Ford A/V8 gear sets. You can buy then new from Winters. Sprinters generally use 10" Ford Freighter.

When I first got my Supermod in the early 90s it was bloody dreadfull. Free up the suspension and it rides the bumps extremely well.3 link both ends and open drive.
I defy you to do it. Takes the spring away and see how much twist you get with a heim joint, maybe 5 deg. Disconect one top link and you have 30 deg plus.Another reason for broken rod ends too.Or pulling the mounts out of the chassis. So called theory is so often BS, it is practicality.And check for heims that bind, some have less movement than others
And yes some Sprinters are still bound up in the front to this day. I can generally pick them on the track.

When the NZ guy won the Oz Midget title in the early 90s with the open drive car[tailshaft not a torque tube] because of superior suspension travel and bite they banned that set up. So called safety, but it made every other car out of date.
If the tailshaft s covered properly it is safer then having a broken torque tube between your legs.

Noel Hurd owe an IRS set up midget with a BMW engine. It did show promise but was banned.
There was at least 2 monocoque midgets built in the 70s, showed promise and were banned.
As I said in Speedway they have to use beam, it is cheap and simple but in theory Independent should be better. And no one is allowed to prove it. Though it would be undoubtedly more expensive. And on a Sprinter forget independent rear. Those 410s have too much power. Ring and pins last only a few meetings.

As an aside my Sports Sedan used a 3 link and panhard.[top link of the top of the diff] And put the power down better than most because the suspension was not trying to pick up the inside wheels. The car could roll and keep both tyres flat on the ground. The sway bar was not there for appearance, it made a hell of a difference to tune the car on diferent tracks.

So as I said those fad buckets with 4 link front suspensions with urethane bushings are so bound up. Use far larger rubber bushings and they will probably be quite acceptable on bitumen roads.
Before anyone ever uses urethane bushings on any road car [and even a racecar] stop and think why the rubber is there. It will bond to the steel sleeves, unlike urethane, it absorbs road noise and shock meaning it takes the load off of components. It flexes considerably meaning a bound up situation is not.It twists in up and down motion and stays attached to the inner sleeve.In some cases meaning the suspension is working.
I have seen so many broken suspension components, caster arms, wishbones, rear suspension arms, panhard/watts and broken suspension pickup points that I will NEVER install the crap in a road car. And with reservation in a race car. That is inspected far more often and critically than a road car.
Genuine parts or premium brand rubber is generally the go, some of the cheapy brands do not seem to last very long.

[cheapracer]

Cheapy, believe me they are bound up.If you use 2 lower links and 1 top one the car rolls. Use 2 top links and the car lifts inside wheels.
That is why manufacturers all use big gooey soft bushes on 4 link rear cars.
So as I said those fad buckets with 4 link front suspensions with urethane bushings are so bound up.

No, this is a technical forum and facts need to be adhered to.

Equal length parallel 4 link do not bind at all, no reason for them to as both sides raise and lower without any rotation of the axle as the pivot points maintain a constant distance from a perpendicular to the ground line through their arc - hence no attempt to twist the axle at any stage.

However if you use unequal or non parallel (or both) links then rotation of the axle is ensured by the links forming a travel arc which then attempts to twist the tube in roll. This is the situation you are refering too and that's when manufacturers use "big gooey soft bushes" that many GM and Japanese 1970's sedans for example that use unequal length links on their live rear axle.

I have just spent many months testing and playing with many locating designs including many variations on the 4 link theme and have arrived at a 6 link solution that allows the beams advantage while eliminating it's biggest disadvantage (no caster control).

You should pop over to one of the many Rock Crawler forums and tell those guys 4 links bind ...

Edited by cheapracer, 06 August 2011 - 02:47.

[Lee Nicolle]

No, this is a technical forum and facts need to be adhered to.

Equal length parallel 4 link do not bind at all, no reason for them to as both sides raise and lower without any rotation of the axle as the pivot points maintain a constant distance from a perpendicular to the ground line through their arc - hence no attempt to twist the axle at any stage.

However if you use unequal or non parallel (or both) links then rotation of the axle is ensured by the links forming a travel arc which then attempts to twist the tube in roll. This is the situation you are refering too and that's when manufacturers use "big gooey soft bushes" that many GM and Japanese 1970's sedans for example that use unequal length links on their live rear axle.

I have just spent many months testing and playing with many locating designs including many variations on the 4 link theme and have arrived at a 6 link solution that allows the beams advantage while eliminating it's biggest disadvantage (no caster control).

You should pop over to one of the many Rock Crawler forums and tell those guys 4 links bind ...
And you can adjust caster on a beam with leaves, wedge,s between the spring and axle. Like most beam axles have used for the best part of a 100 years!! And on a race type set up caster is as simple as cracking a couple of jam nuts and winding the top arm shorter, or the bottom ones longer.

Aaaaahm, that is a leaf spring. Not a 4 link. Most o the wheels would be off the ground with one. Unless they have big gooey bushes,and at those angles they would bind too.
And it is so simple to adjust caster with a beam, on leaf springs use a wedge between the spring and axle. Like manufacturers have done for a 100 years. Or on a race type set up crack a couple of jam nuts and wind the axle back. A beam cannot be adjusted for camber, and camber only. You can build an axle with camber but it will drive pretty terrible. Though may corner ok, xcept for the bump steer!!

Edited by Lee Nicolle, 06 August 2011 - 09:36.

[cheapracer]

Aaaaahm, that is a leaf spring. Not a 4 link. Most o the wheels would be off the ground with one. Unless they have big gooey bushes,and at those angles they would bind too.
And it is so simple to adjust caster with a beam, on leaf springs use a wedge between the spring and axle. Like manufacturers have done for a 100 years. Or on a race type set up crack a couple of jam nuts and wind the axle back. A beam cannot be adjusted for camber, and camber only. You can build an axle with camber but it will drive pretty terrible. Though may corner ok, xcept for the bump steer!!

My error, I posted the wrong link, it was from before and after shots and obviously that was a before and now I can't find the site again .... mind you having leaf springs doesn't stop from having a winning 4 link formula, just ask any Group 4 RS Escort runner who won WRC and world rally championships.




Anyway, you are stuck in a "speedway beam" rut, I not only have a beam fully adjustable for everything sitting on my car at this very moment which also offers dynamic caster and camber changes, I also have a few rejects laying in my shop's rubbish pile that offer similar.

Above I mentioned why 4 links don't bind (within the specific parameters I mentioned), why not offer your view of why they do bind?

Or did you want to wait until after I show you pictures of a real non binding 4 link beam in action?

[cheapracer]

Oh and FWIW, there's a forum member who had 4 unequal length link rear end binding problems on a smaller English special that put him into a wall at Amaroo Park(?) and resolved it all by getting the 4 links into the parameters mentioned above.

Ray Bell may know who I mean and may be able to help with the actual thread location please?

[Lee Nicolle]

My error, I posted the wrong link, it was from before and after shots and obviously that was a before and now I can't find the site again .... mind you having leaf springs doesn't stop from having a winning 4 link formula, just ask any Group 4 RS Escort runner who won WRC and world rally championships.




Anyway, you are stuck in a "speedway beam" rut, I not only have a beam fully adjustable for everything sitting on my car at this very moment which also offers dynamic caster and camber changes, I also have a few rejects laying in my shop's rubbish pile that offer similar.

Above I mentioned why 4 links don't bind (within the specific parameters I mentioned), why not offer your view of why they do bind?

Or did you want to wait until after I show you pictures of a real non binding 4 link beam in action?

Pic is hard to make out but I do see big rubber bushes. A 4 wd would never have anything else.
Take 3" axle, have 4 say 24" parralel radius arms taken off it with say 8" centres using heim joints or the small urethane bushes that most street rods use, say a 25-30mm sleeve with a 1/2 bolt going through it. With all the springing and shocks removed try and lift one side, it may move 5 deg before the other side follows. On the road they will move a bit more as the arms and pickups flex more. Now take one top arm off [left side for a dirt car] and all of a sudden you have 30 deg of movement before the other side wants to follow.The bigger the centres you will gain a very small amount of movement. Without all the lengthening and shortening bump steer that the rubberbushes allow. Which is engineeered in a road vehicle to be acceptable, until you put big sticky tyres on it!!
Virtually all road cars with a beam rear axle have to top links face in, so the car will have more roll

And yours is not a true beam axle, it is a twin beam, eg 2 wishbones. It looks like it should work ok, in fact would be quite good for a hot rod. Though not traditional. That bucket above has very small centres, any roll it is getting is those very long spindly radius arms flexing. That was what my comments were always about. That car is totally bound up, and totally stupid with those motorcycle tyres.

And there is nothing terribly wrong with leaf springs, but once again why do leaf springs have shackles, because they lengthen and shorten through their movement. And allow for twist in the sprig as one wheel goes up and the other says down. When you put eg, nylon bushes in the eyes they do not twist as much. Ok for circuit racing where you do not need much roll but bloody awful for off road. And how many rally cars have leaf springs now, none. Or even beam axles. Leafs and live axle is mostly commercials only, and on a passenger cars most live axles use coils. Some wagons etc still use the simple and better for load carrying leaves.

But lets face i the last vehicles with beam front axles are going wishbone of some sort to make them ride better and handle better. Only trucks are still normally beam, 4wd are now nearly all wishbone. Though service costs will increase with CVs etc

Edited by Lee Nicolle, 07 August 2011 - 00:30.

[cheapracer]

And yours is not a true beam axle, it is a twin beam, eg 2 wishbones.

I am refering to my front single beam (my rear is a split beam and has 2 halves with a pivot in the middle) and whats a "true beam" anyway? A Model T is different to a Speedway car which is different to a Volvo truck.

In my mind a beam is a singular uninterrupted suspension component that connects the 2 sides together as well as supporting all the major components.

Virtually all road cars with a beam rear axle have to top links face in, so the car will have more roll

No, cars that have top links facing in are using them for lateral axle location (people seem to refer to this setup currently as a "Satchell Link"), there's plenty of 4 link (and usually a Panhard rod) mass production cars with live rear axle such as the Holden Commodore, 80's and 90's Toyotas, Mazdas etc. that don't angle.

If I get a moment this week I'll pull out one of the older beams and show you whats possible.

[Lee Nicolle]

I am refering to my front single beam (my rear is a split beam and has 2 halves with a pivot in the middle) and whats a "true beam" anyway? A Model T is different to a Speedway car which is different to a Volvo truck.

In my mind a beam is a singular uninterrupted suspension component that connects the 2 sides together as well as supporting all the major components.





No, cars that have top links facing in are using them for lateral axle location (people seem to refer to this setup currently as a "Satchell Link"), there's plenty of 4 link (and usually a Panhard rod) mass production cars with live rear axle such as the Holden Commodore, 80's and 90's Toyotas, Mazdas etc. that don't angle.

If I get a moment this week I'll pull out one of the older beams and show you whats possible.

Not parralel links, they are long and short links and all have huge gooey rubber to allow for the misalignment.Which on some can be huge.and cause rear steer.Or any GpC GpA racer on Commodores. Ask Dick Johnson about them on XEs.
A Volvo truck has a beam, as does a T model. A pivot in the middle is a wishbone.

[cboy]

...Why anyone would use Ford truck twin I-beam front end on a street rod is what makes no sense to me. It's heavy, bulky, ugly, and hilariously overbuilt the application.

First, let me thank cheapracer for posting up the link to my book in his initial post. He must feel like I am stalking him since I seem to follow him around on the web where he has kindly referenced "The Scratch-Build Hot Rod" over the past few days. Also, thanks to the many of you who have taken the time to click that link and browse some, or all, or the chapters. Also, let me apologize for not responding in this thread sooner. As a newcomer to your site, I had to sit through the required "waiting period" before getting authorization to post.

Since a part of this thread has been devoted to twin-beam or split-beam front suspensions, I wanted to just respond to Magoo's observations above. I have three rods which utilize the Ford twin-beams from F-series trucks, so I am obviously quite prejudiced.

I think Magoo's comments are somewhat dependent on what year twin-beams one chooses. Personally I limit myself to 1976 to 1981 and further try to keep my choice between 1976 and 1979. These beams are forged, equal length AND they all come stock with disk brakes.

Beauty is in the eye of the beholder so I won't quarrel with Magoo's "ugly" label. I can only offer a couple of photos in support of my use of twin-beams on hot rods. This first photo is from my scratch-build '32 pickup. I'd conservatively estimate that 95% of people who see it for the first time think this truck has a traditional drop forged hot rod axle. It is only on careful inspection that they discover it is a F-150 front end mounted with air bags as shown in the second photo which was taken during fabrication.





This second set of photos is from my sedan delivery which is featured in the book cheapracer linked above. I built this suspension with an underslung frame and an experimental quarter elliptical leaf spring setup. Again, from the front view it appears much like a traditional forged axle which gives way on further inspection to be twin beams.








To answer your question as to "why" a hot rodder would ever use the ford I-beams I can only submit my personal observations based on my limited experience.

1) Cost. For about the cost of buying a straight axle front suspension from Speedway or similar hot rod catalog outlet, I can buy an entire donor vehicle (F-series pickup) which will provide me with independent front suspension including disk brakes, a stout V8 engine (302 to 460), a hearty transmission (C6 automatic or stick shift) and a very desireable rear end (either Ford 9 inch or Dana 44). From that same donor I can also salvage the steering column, the pedals and pedal hardware, full wiring harness, leaf springs, and an assortment of other odds and ends. Around where I live, (Northern WI/USA) I pay anywhere from $150 to $300 for these old trucks and for that I get virtually every essential part I need for my builds. I can't think of a single other donor vehicle that provides so much for so little.

2) Looks. To my eye, the 1976-1979 twin beams are very traditional looking. And while I respect Magoo's viewpoint that they are heavy, bulky, and ugly, I have never heard similar comments at any of the shows I attend once people see the suspension installed. In fact, these cars have won any number of awards including a few "Best of Show" trophies. So the suspensions can't be totally in the dumpster in terms of looks.

3) Ride. I have built cars over the years with virtually every front suspension you can image. I would put the ride quality of the twin beams far and above the quality of a tradition straight axle and just a notch or two below the ride provided by A-arm (Mustang II type) front suspensions.

4) Versatility. The twin-beams after 1975 all come stock with disc brakes. And twin-beams from '75 or earlier can be converted to the later model disc brakes as a bolt-in swap.

5) Uniqueness. Yes, a lot of us hot rodders like to be a little unique...to do things a little differently or with a little of our own "mark" on each build. True, twin I-beams ARE a little out of the ordinary. But that is a plus in my book, not a negative.

6) Hotroddyness. Okay, so its not a real word. But what I'm talking about is the old days of traditional hot rod building when we didn't have the internet or big catalog outfits where we could buy every part we needed already made up for us in a nice factory. Instead we had to scrounge parts and pieces wherever we could find them and THEN make them all work together. Personally, that is one of my favorite parts of building a rod. Obviously, not everyone shares those same feelings nor do they need to. But for me, doing it this way adds the spice which makes this sport meaningful and rewarding to me.

Clearly there are some drawbacks to twin I-beams, just as there are drawbacks with any front suspension. There major drawbacks I see are:

1) Track width. Twin beams can only be adjusted a couple inches at best in terms of front track width. This can limit their use, particularly on full fendered cars. On open wheel cars track width is less of an issue and for scratch-build cars, where frame width can be fully adjusted, twin-beams are very compatible.

2) New geometry. Twin beams work differently than traditional axles and A-arms. Builders need to spend some time getting familiar with the engineering and geometry involved in setting up twin beams. But this is well within the capabilities of virtually any rodder with a modest about of experience. Basically, just take copious measurements off the donor vehicle and then build your frame and mounting hardware to match.

3) Tire wear. This is an old and well known bugaboo related to twin beams which I cover in some detail in this chapter of the book. What I have discovered, however, is that the caster and camber problems most Ford owners complain about can both be eliminated in a hot rod setup via the use of a 4-bar setup coupled with some way of adjusting spring height (air bags, adjustable coil overs, or adjustable leaf springs). The camber issues can not be totally eliminated, but they can be greatly minimized.

The great thing about car building and hot rodding is that each of us gets to build things "our way". We will never all agree on what is beautiful or what is ugly. And that is part of the joy we get out of doing what we do.

[cboy]

...The problem that arises when people modify them is that it usually involves putting wheels on them that are not suited to the design. In particular looking at the twin I beam set-up as depicted in fig.3-3those wheels are all wrong . Have a look at where the king pin is located. A small diameter wheel with wide low profile tyre results in a significant scrub radius. That means as I'm sure you're aware that those fat tyres at the outer shoulder act like big levers and will pull you around all over the place dictated by terrain and road contour. Often this leads to constructors compensating for this by cranking in a good deal of caster to try to give it straight line stability. That translates to heavy steering , particularly in tight situations like car parks. This Twin I - beam installation has little caster at all. I can't imagine this would be very stable on the road.

There's a lot of meat in what fredeuce offers here so let me just start by posting the photo of the twin beam setup he is talking about.



This is an '81 twin beam and you will quickly notice that the passenger side axle is shorter than the driver's side axle. This creates a bit of a fabrication challenge and in my view, doesn't look nearly as good as the equal length '76-'79 twin beams. But I used the axles just to see what the results would be. These next couple photos show the completed car.







But getting back to fredeuce's comments, I'm a little perplexed as to how to respond. Based on his post this car should handle terribly and be all over the road - if not downright unsafe. For what it's worth, the exact opposite is true. I've built some truly ill-handling cars in my past, so I make no claim of knowing what I'm doing. But this particular car handles like a dream. No bump steer. No wandering. No push-pull effect due to road terrain. And the wheels return to center and go down the road like an arrow.

Clearly fredeuce has a far better grasp of the engineering concepts involved here than I would ever hope to have. So I am at a loss to explain why the car handles flawlessly in real life.

To shed a little more light let me just say that I run about 6 degrees of caster in each axle. I don't consider that excessive and it certainly does not result in a "heavy steer" situation. Also, the front tires are 195/50 x 15. And I am running power steering on the car, which might compensate somewhat for the poor handling fredeuce predicts.

As a side note, I have two other twin-beam equipped hot rods. The '32 pickup in the first two pictures runs 205/50 x15 front tires and has power steering. The sedan delivery in the final two pictures runs 215/70 x 15 tires and has manual steering. All three cars run the same caster and all three have equivalent handling characteristics although the manual steer obviously requires a bit more muscle to turn.

[Lee Nicolle]

While personally I think a big heavy truck axle is way too big this should work ok, and not bind up.And as you say a F truck gives you a lot of bits, though mostly too heavy as they are truck items. That includes the 9" diff. Which are a truck item at best.
Though one car is using those urethane eye bushes and they do not twist well at all. I have seen hotrod chassis pickups fail because of them. A bigger rubber eye bush will be far better.I have seen them, about and 1 1/2" with a 1/2 id steel sleeve in them with a 5/8 thread. Where they come from I do not know but look good for that sort of use And the heim joints ofcourse give an all metal ride. I hope they are not alloy radius arms, not strong or durable enough for extended road use. The steel ones are though but cost too much.
Though what Fred says about the huge scrub radius is true, the original rims wrap around the kingpins far more and minimise the scrub radius. Some 16" rims and 600x16 or even a 205x70x16 would help quite a lot. Really those 12" F truck brakes are too big. Some 11" passenger car ones with smaller callipers would then allow more offset in. 70s 80s mid size US cars are very similar to our Oz Falcons and should go right on the spindles. And less unsprung weight flailing around
And using rounded shoulder OEM size tyres would help too, eg 205x65x15 than the square shoulder wankmaster GTs. They make a full size car drive far nicer

Edited by Lee Nicolle, 07 August 2011 - 22:46.

[cheapracer]

Not parralel links,

A pivot in the middle is a wishbone.

I didn't mention unequal length or not which almost all of them are because of that annoying back seat thingy in the way, I merely counted your claim that they all angle in.

When it's a tube with a rotary pivot in the middle it's not a wishbone.

In reference to DJ's XE, when DJ finally stopped listening to that idiot ex-F1 mechanic of his who had every answer for the rear end, fired him and started sorting out the front end, they started to get some where. I wonder if Greg ever had anything to do with that?

cboy, excuse Magoo, lucky bastard has the privilege of seeing the world's finest Hot Rods literally daily and thanks for dropping by.

[cboy]

...
cboy, excuse Magoo, lucky bastard has the privilege of seeing the world's finest Hot Rods literally daily and thanks for dropping by.

He seems to know what he is talking about and I have a great deal of respect for anyone who understands the engineering and geometry of suspension systems. I'm always seeking new and better ways of doing things so I try to understand the observations people make as best I can. But I certainly take no offense. Hot rodding is all about personal tastes...that's why we "customize". I get to build what looks good to me and Magoo gets to build what looks good to him. And everybody's happy.

Edited by cboy, 08 August 2011 - 03:46.

[mariner]

I have zero hot rod knowledge but talking about beam and split axles generally there are two " expert" sources who have been there and done it very sucessfully, Arthur Mallock and his rigid rear axle U2's and Spen King whose SUV, the 1970 Range Rover, pretty much created the luxury SUV with good road handling.

The U2 oriignally had the classic four links and Panhard rod rear layout which had ball joints and didn't bind. Then they went to the Mumford link to get roll centre choice versus Panhard rod and introduced the so called " TAM or trailing arm magic" which put all four longtitudinal links at different angles to improve traction and roll steer. It was covered in detail in Racecar engineering.

Spen King used a solid front axle with leading links on the Range Rover with rubber bushes but he made it handle properly on the road unlike many other SUV's ( including the Land Rover).

Spen King was a very broad thinker, he did the complex De dion on the Rover 2000 then many years later did a solid axle on the Rover 3500 which he reckoned was as good. It was torque tube, side links and Panhard rod but with some clever damper spring mounting geometry to improve roll stiffness with relatively soft springs.

Of course the first Louts's also used a split front axle as did the early U2's!!

[bigleagueslider]

I have three rods which utilize the Ford twin-beams from F-series trucks, so I am obviously quite prejudiced.

I think Magoo's comments are somewhat dependent on what year twin-beams one chooses. Personally I limit myself to 1976 to 1981 and further try to keep my choice between 1976 and 1979. These beams are forged, equal length AND they all come stock with disk brakes.

cboy,

Ford has used that "twin I-beam" front end on its trucks for several decades. Your rod pictures show a transverse leaf spring, but for the last 30 years Ford has used coil springs. The twin I-beam front suspension was used by Ford because it has excellent load capacity. But the downside with these suspensions was their propensity to chew up steering tie-rods.

[johnny yuma]

I guess a "show rod" is not really a motor vehicle in a sense it is eye candy. However a "daily driver" or "tourer" hot rod must be built so it has civilised dynamics,hopefully superior to the 1930s basic cheap end car it derives from.in a way a clubman is a scaled down hotrod.
One of my favourite Historic Racing specials always at Phillip Island is the dark blue 32 Ford with original flathead V8,mudguards removed,telescopic shocks wrangled on....OK lets go racing in Archie and Jughead cars on bitumen !!!.....performs really well.