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#1 Doug Nye

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Posted 19 May 2022 - 12:09

In recent conversation with some TNF friends the question of Formula 1 car stressed and/or semi-stressed engine mountings arose.  Don't worry, we are taking medication for this condition...

 

Regardless, the 1954-55 Lancia D50 V8 came up as an early example of a semi-stressed engine design, using the rigidity of the V8 castings themselves to stiffen the front end of the otherwise multi-tubular chassis frame.  See below:

 

REVS-1955-LANCIA-D50-1.png

 

These first two Revs Digital Library images show right and left-hand sides of the original-style 1954-55 Lancia V8 engine mounting, with the unit's top-end bolted rigidly fore and aft to the tubular frame sections.

 

REVS-1955-LANCIA-D50-2.png

 

Then (below) this is the 1956 Lancia-Ferrari D50 or D50A adaptation with detachable top tubular frame member enhancing frame rigidity through the engine bay.

 

REVS-1956-LANCIA-FERRARI-D50-1.jpg

 

REVS-1957-LANCIA-FERRARI-801.jpg

 

But then at Monaco for the 1957 GP, 'Phil' captured this view of the Lancia-Ferrari 801 (the slim-bodied, pannier-free final development of the front-engined F1 Ferrari V8 series) which apparently depicts a reversion to the original style of semi-stressed engine mount, any provision for upper reinforcing tubes having been deleted.

 

I found this interesting.  But it's soon time for my medicine...

 

Photos Copyright: The Revs Digital Library

 

DCN

 

 

 



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#2 cpbell

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Posted 19 May 2022 - 12:21

Did Ferrari continue with semi-stressed engines in the Dino series of GP cars?



#3 Doug Nye

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Posted 19 May 2022 - 13:11

Nope.

 

DCN



#4 Michael Ferner

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Posted 19 May 2022 - 14:13

Many thanks for this lavishly illustrated piece of detective work, Doug - I find it very interesting, too. Does it mean I now also need medication?

 

(Or, maybe, I should stop making alternative plans for Tuesday evenings... :blush:)



#5 cpbell

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Posted 19 May 2022 - 15:53

Nope.

 

DCN

Thanks Doug.



#6 Arjan de Roos

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Posted 19 May 2022 - 17:02

 

 

REVS-1957-LANCIA-FERRARI-801.jpg

 

But then at Monaco for the 1957 GP, 'Phil' captured this view of the Lancia-Ferrari 801 (the slim-bodied, pannier-free final development of the front-engined F1 Ferrari V8 series) which apparently depicts a reversion to the original style of semi-stressed engine mount, any provision for upper reinforcing tubes having been deleted.

 

I found this interesting.  But it's soon time for my medicine...

 

Photos Copyright: The Revs Digital Library

 

DCN

 

Long time Ferrari mechanic (and co-driver) Pasquale Cassani at work. 



#7 arttidesco

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Posted 19 May 2022 - 17:53

 

But then at Monaco for the 1957 GP, 'Phil' captured this view of the Lancia-Ferrari 801 (the slim-bodied, pannier-free final development of the front-engined F1 Ferrari V8 series) which apparently depicts a reversion to the original style of semi-stressed engine mount, any provision for upper reinforcing tubes having been deleted.

 

I found this interesting.  But it's soon time for my medicine...

 

Photos Copyright: The Revs Digital Library

 

DCN

 

IIRC Ferrari always was about the engines, never about pifling chassis details  :blush: 

 

I'll get back in my straight jacket ;-) 



#8 Roger Clark

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Posted 19 May 2022 - 18:03

There are a lot of us needing that medication.

 

Ferrari had five Lancia-based cars at Monaco in 1957.  Two of them had new Ferrari designed frames. According to the Racing Car Review: "there was no longer any need to have the additional bracing struts from the bulkhead to the front suspension, as introduced by Ferrari when he first took over the cars". Some of the cars had modified Lancia front suspension and others had Super Squalo suspension but I don't know which this is.



#9 ReWind

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Posted 19 May 2022 - 18:21

Can anyone put some markings on the photographs to show me where I have to look at in order to see what the talk is all about?

I would be grateful.



#10 Tom Glowacki

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Posted 19 May 2022 - 18:31

Look at the back end of the cylinder heads. between the camshaft covers and you will see a flange bolted to the firewall.  At the front, sight straight up from the upper suspension pick-up and you will see a bracket bolts to the front of the cylinder head.



#11 GregThomas

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Posted 19 May 2022 - 19:13

Ferrari were very conservative in the period when it came to chassis.  The big tube ladder frame had done them well for some time and I suspect there was resistance to an "outside idea" - even if it was Jano's

Another factor may have been ease of engine replacement. The stressed engine i suspect is harder to change than one sitting between frame rails.

 

It occurs to me also that given Ferrari was "all about the engines"  there was probably an institutional dislike of putting external loads through an engine. It is after all a bolted up collection of parts within which you're trying to keep the oil.



#12 Doug Nye

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Posted 19 May 2022 - 20:01

There are a lot of us needing that medication.

 

Ferrari had five Lancia-based cars at Monaco in 1957.  Two of them had new Ferrari designed frames. According to the Racing Car Review: "there was no longer any need to have the additional bracing struts from the bulkhead to the front suspension, as introduced by Ferrari when he first took over the cars". Some of the cars had modified Lancia front suspension and others had Super Squalo suspension but I don't know which this is.

 

Good point Roger - the early Lancia D50s used transverse-leafspring front suspension - the Ferrari adoption of 'Super Squalo' suspension for Lancia-Ferrari development featured the coil-springs shown in the 801 workshop photo.

 

DCN



#13 Sterzo

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Posted 19 May 2022 - 21:05

According to the Racing Car Review: "there was no longer any need to have the additional bracing struts from the bulkhead to the front suspension, as introduced by Ferrari when he first took over the cars". Some of the cars had modified Lancia front suspension and others had Super Squalo suspension but I don't know which this is.

That's fascinating, and raises the question: why would a change of springing medium negate the benefits of a stiffer car? Were the coil springs more effective at keeping the stresses within the wishbone area, rather than transfering forces into the frame?



#14 GregThomas

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Posted 19 May 2022 - 23:38

Depends which forces you're talking about. The classic transverse leaf spring has two functions. Suspension springing - and as an anti-roll preventer/bar.

Using coil springs largely isolates the two functions.

Ferrari may have decided the Lancias were too stiff in roll at the front and having done the same mod between 500 and Squalo models, simply changed to what they knew.



#15 Roger Clark

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Posted 20 May 2022 - 09:02

Was the change in springing medium necessarily connected to the deletion of the bracing struts?  It could be that the changes Ferrari made to the frame made them unnecessary. I think (I’m not certain) that the coil sprung cars had a n anti-roll bar to compensate for the loss of the leaf spring. 



#16 Charlieman

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Posted 20 May 2022 - 09:22

Depends which forces you're talking about. The classic transverse leaf spring has two functions. Suspension springing - and as an anti-roll preventer/bar.

Using coil springs largely isolates the two functions.

Ferrari may have decided the Lancias were too stiff in roll at the front and having done the same mod between 500 and Squalo models, simply changed to what they knew.

A transverse leaf spring always provides a variable rate owing to the way that lever lengths change (true to a lesser extent for many coil spring layouts). Depending on how a transverse leaf spring is mounted (single or duo fixed points, pivot mount), resistance to lateral weight transfer varies. Cooper perhaps optimised the design, but coil spring plus anti-roll bar provides a simpler, more adjustable solution.



#17 BRG

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Posted 20 May 2022 - 18:43

I would be a little surprised if the Lancia/Ferrari 500 was the first to use the engine as a stressed member. 

 

My knowledge is rather sparse but one thing I have learnt is that whenever some innovation is introduced, it turns out that the Atlas-Fotheringay Type 3 of 1908 had already employed it.


Edited by BRG, 20 May 2022 - 18:43.


#18 Tim Murray

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Posted 20 May 2022 - 19:27

This very old thread suggests that the engine in several earlier cars (1914 GP Mercedes, Bugatti T35 etc) made a significant contribution to overall chassis stiffness, while a 1920 Miller design had the engine as a completely-stressed member.

First F1 car to use the engine as a stressed part of the car

#19 Ray Bell

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Posted 20 May 2022 - 21:27

The Model K Ford certainly became a lot stiffer when the engine was fitted up...

 

With the crankcase having strong attaching points each side of each end, this was probably a side-effect of the design.

 

Proving it was needed was the fact that torsional loads at walking speeds would stop the engine rotating.



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#20 Tom Glowacki

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Posted 20 May 2022 - 21:47

I would be a little surprised if the Lancia/Ferrari 500 was the first to use the engine as a stressed member. 

 

My knowledge is rather sparse but one thing I have learnt is that whenever some innovation is introduced, it turns out that the Atlas-Fotheringay Type 3 of 1908 had already employed it.

As, for example, the 1956 International Harvester Farmall Tractor.amongst other farm tractors in which the engine, transmission, and differential form the entire chassis.


Edited by Tom Glowacki, 20 May 2022 - 21:51.


#21 Lee Nicolle

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Posted 21 May 2022 - 07:33

In recent conversation with some TNF friends the question of Formula 1 car stressed and/or semi-stressed engine mountings arose.  Don't worry, we are taking medication for this condition...

 

Regardless, the 1954-55 Lancia D50 V8 came up as an early example of a semi-stressed engine design, using the rigidity of the V8 castings themselves to stiffen the front end of the otherwise multi-tubular chassis frame.  See below:

 

REVS-1955-LANCIA-D50-1.png

 

These first two Revs Digital Library images show right and left-hand sides of the original-style 1954-55 Lancia V8 engine mounting, with the unit's top-end bolted rigidly fore and aft to the tubular frame sections.

 

REVS-1955-LANCIA-D50-2.png

 

Then (below) this is the 1956 Lancia-Ferrari D50 or D50A adaptation with detachable top tubular frame member enhancing frame rigidity through the engine bay.

 

REVS-1956-LANCIA-FERRARI-D50-1.jpg

 

REVS-1957-LANCIA-FERRARI-801.jpg

 

But then at Monaco for the 1957 GP, 'Phil' captured this view of the Lancia-Ferrari 801 (the slim-bodied, pannier-free final development of the front-engined F1 Ferrari V8 series) which apparently depicts a reversion to the original style of semi-stressed engine mount, any provision for upper reinforcing tubes having been deleted.

 

I found this interesting.  But it's soon time for my medicine...

 

Photos Copyright: The Revs Digital Library

 

DCN

I have never really been a fan of using the engine as a stressed member. Though with engines designed to be mounted that way it is a very sound idea.

That last pic though I love those brake drums.



#22 Lee Nicolle

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Posted 21 May 2022 - 07:39

As, for example, the 1956 International Harvester Farmall Tractor.amongst other farm tractors in which the engine, transmission, and differential form the entire chassis.

As do nearly every farm tractor made. Big strong heavy castings. Great for strength put putting a clutch in one means splitting the tractor in half. Once did one on a Fergy petrol.

Next one that needed doing we got a bloke in to do it!!.



#23 BRG

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Posted 21 May 2022 - 09:16

As do nearly every farm tractor made. Big strong heavy castings. Great for strength put putting a clutch in one means splitting the tractor in half. Once did one on a Fergy petrol.

Next one that needed doing we got a bloke in to do it!!.

This explains all those YouTube clips I have seen where tractors come in half during extreme use!



#24 Charlieman

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Posted 21 May 2022 - 09:19

I have never really been a fan of using the engine as a stressed member. Though with engines designed to be mounted that way it is a very sound idea.

Production car manufacturers have never liked the idea for vibration reasons. The Bugatti T35 and variants almost classify as a production car, of course. Production engines power the majority of historic racing cars but a great many have been used as partially-stressed members -- see the vertical plate with cradle design in many Lolas, attributed to John Barnard. Production racing cars and engines have to be reliable.

 

The Cosworth DFV is often cited as the first racing engine to be used as a stressed member which is nonsense. Perhaps it is the first which was intended for use outside the manufacturer's racing team.

 

Ten years after inheriting the Lancia D50 design, Ferrari used the engine as a stressed member in F1 cars, before returning to beam or cradle mounts for the (1950s derived) V12 3 litre cars. With the flat 12, Ferrari recognised that stressed member was the way to go. Who built the last F1 car with a non-stressed engine?



#25 guiporsche

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Posted 21 May 2022 - 12:28

One small note. In 1966, it's not because Ferrari did not that Ferrari was unconvinced. We simply do not know it, but what we do know is that money was tight, which was why the sports-car derived V12 was used. 


Edited by guiporsche, 21 May 2022 - 12:29.


#26 Ray Bell

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Posted 21 May 2022 - 12:43

Of course there were individual cars with the engine as a stressed member...

 

The Clisby hillclimb car of c1950, using a Douglas flat twin motorcycle engine.

 

And the spin-off from that, the Eclipse Zephyr built by Eldred Norman using a Ford Zephyr engine.



#27 Roger Clark

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Posted 21 May 2022 - 13:29

Didn't most of the 3-litre V12s of the late 60s need to carry fuel in the monocoque alongside the engine, thus removing any benefit of a fully stressed engine?



#28 arttidesco

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Posted 21 May 2022 - 16:48

Didn't most of the 3-litre V12s of the late 60s need to carry fuel in the monocoque alongside the engine, thus removing any benefit of a fully stressed engine?

Not sure which cars you are thinking of Roger, but from memory the late 60's Ferrari, Matra, BRM and Maserati powered Cooper did not carry fuel in the monocoque/chassis frame alongside the engine rather in fuel tanks alongside and/or behind the driver ?



#29 Roger Clark

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Posted 21 May 2022 - 18:01

You're probably right; I didn't check.



#30 Doug Nye

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Posted 21 May 2022 - 20:25

The contemporary problem with running a V12 engine as a fully-stressed structural member in the manner of a 1967-forward DFV V8 was largely its 6-cylinder length compared to the V8's 4-cylinder length.  Compare the oblong planform of a V12 to the square planform and cubic proportions of the V8. The V12 was in relative terms long and whippy, its long crankshaft's main bearings more susceptible to binding should that crankcase be twisted. I recently posted a shot of the '67/68 Ferrari 312 chassis with engine removed to expose the engine bay between its long rear semi-monocoque chassis legs.  The BRM conformation was similar until Tony Southgate's 1970 P153.  Simplistic descriptions, but that's in essence the way it was...

 

DCN



#31 Roger Clark

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Posted 22 May 2022 - 08:49

I have been doing some investigation into the configuration of the Lancia/Ferraris during 1957. It may be of some interest to those whose medication hasn't started working yet. The source of most of this is Denis Jenkinson's race reports, Notes on the Cars and the Racing Car Review. There are some mysteries particularly concerning the cars built for Mike Hawthorn. I would be grateful for any comments, additions and corrections.

Ferrari sent six cars to Argentina. Three of them had new Ferrari designed frames which, as mentioned above, removed the need for bracing struts. Five of them had the standard Lancia front suspension of equal length wishbones and low mounted leaf spring. One car had unequal length wishbones, achieved by welding extensions onto the lower limbs but still leaf springs. I should mention that DSJ didn't go to Argentina so relied on what he was told but he had good connections within the team.

The first European race was Syracuse. Collins' car had unequal length wishbone but coil springs replaced the leaf. It was the first appearance of the narrow body which became common in 1957. Musso had a standard 1956 configuration.

At Naples, Collins had the same front suspension as Syracuse but also independent rear suspension. He won the race but the IRS was not seen again. Hawthorn had a car with larger cockpit, to quote DSJ: "to accommodate the bulk of this oversize driver". DSJ said the the larger cockpit was achieved by moving the engine forward and that the wheelbase was unchanged. THIS CONTRADICTS MOST OF WHAT IS WRITTEN ELSEWHERE. Hawthorn's car also had Super Squalo front suspension. I wonder whether this provided extra room to move the engine. Both cars in Naples had 1956-style wide bodies.

At Monaco, there were two cars with Ferrari frames, modified Lancia front suspension and narrow bodies, two "Hawthorn specials" and a spare to the usual 1956 configuration. Collins crashed the long cockpit car intended for Hawthorn while trying it in practice. It was beyond immediate repair and Hawthorn started the race in the 1956 car which he felt handled better. He could presumably fit into this but later in the race he took over von Trips' car but handed it back after very few laps as it was too cramped. This car had one of the Ferrari frames so possibly they were smaller than the early Lancia ones.

After that, things settled down a bit. The long cockpit car, Super Squalo suspended car was taken to the races but Hawthorn rarely, if ever, raced it. He could, of course, have had another special with longer cockpit and wheelbase but I couldn't find that mentioned in Jenks' writing. At Monza, he said that there was a new car with extended wheelbase, evidenced by the increased gap between the exhausts and the rear wheels. It is possible that this car appeared earlier and that our reporter missed it. It does seem unlikely that Ferrari would build a new car for their last race. After Monza the cars were consigned to the Maranello scrap heap and physical evidence was lost.

#32 Ray Bell

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Posted 22 May 2022 - 11:52

Nice work, Roger...

 

I'm sure I'm not the only one who appreciates the effort you've expended in gathering all of this information.



#33 MarkBisset

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Posted 22 May 2022 - 22:23

Well said Ray, and great work Roger.

 

The variations of specification between cars is incredible.

 

Perhaps it could be said that if the definitive ‘57 801 didn’t have additional tubular bracing under the bonnet that Jano’s original design approach was ‘spot on’, where that is defined as sufficient torsional stiffness



#34 Doug Nye

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Posted 28 May 2022 - 20:23

I have just noticed these explanatory photos on the excellent Grand Prix Models website, showing the 1956-type Lancia-Ferrari engine-bay area, as modelled to 1:12-scale by the outstanding (if formidably expensive) Hiro L-F kit .

 

Without engine and additional upper frame longerons installed:

 

Screenshot-2022-05-28-at-21-15-33.png

 

With all three installed:

 

Screenshot-2022-05-28-at-21-14-48.png

 

DCN



#35 mariner

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Posted 29 May 2022 - 01:11

There is one practical problem with a semi - stressed engine design which is getting the engine back in after removal. With a fully stressed layout like a Cosworth DFV the engine is bolted onto the chassis by four bolts and only has to line up there.

 

With a semi stressed layout the engine has to fit the chassis front and back where the intervening frame may have distorted. with use.

So every engine change requires possibly force flexing the chassis to fit the engine holes back in line.

 

Maybe this happened on the Lancia based cas as tehy went multiple races and led Ferrari to give up on the idea.



#36 Lee Nicolle

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Posted 29 May 2022 - 02:38

The contemporary problem with running a V12 engine as a fully-stressed structural member in the manner of a 1967-forward DFV V8 was largely its 6-cylinder length compared to the V8's 4-cylinder length.  Compare the oblong planform of a V12 to the square planform and cubic proportions of the V8. The V12 was in relative terms long and whippy, its long crankshaft's main bearings more susceptible to binding should that crankcase be twisted. I recently posted a shot of the '67/68 Ferrari 312 chassis with engine removed to expose the engine bay between its long rear semi-monocoque chassis legs.  The BRM conformation was similar until Tony Southgate's 1970 P153.  Simplistic descriptions, but that's in essence the way it was...

 

DCN

The actual frame of the car really needs to be fairly rigid. Those front engine cars with mounts on the front are going to twist the engine. Twist it 1 though and you have possible wiped out a bearing or two. The modern version of this is ofcourse engine plates front and rear of the engine. Better as there is more support. Very good on  SB Chevs as they have mounting lugs on the front of the block. Actually for engine mounts. Though using an engine plate on the back of the block causes issues for a manual trans car as the spigot of the gearbox hardly locates after moving the gearbox back 6mm. And the gearbox still requres a mounting as the driveshaft causes very significant loads. Ditto for autos as well. 

I have seen broken extension housings on gearboxes mounted so. Both auto [drag racing] and manual road racing.

On rear engined cars with the suspension hanging off the engine not so good for production engines though for engines designed to be used as a stressed member it should be fine. Though what happens to those engines when they crash?? I suspect they will start breaking lugs off of engines.



#37 GregThomas

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Posted 29 May 2022 - 03:29

There is one practical problem with a semi - stressed engine design which is getting the engine back in after removal. With a fully stressed layout like a Cosworth DFV the engine is bolted onto the chassis by four bolts and only has to line up there.

 

With a semi stressed layout the engine has to fit the chassis front and back where the intervening frame may have distorted. with use.

So every engine change requires possibly force flexing the chassis to fit the engine holes back in line.

 

Maybe this happened on the Lancia based cas as tehy went multiple races and led Ferrari to give up on the idea.

 My thoughts after seeing the pics are that the struts are original Lancia.  Used on the jig for construction - and whenever you wanted to move the chassis without an engine fitted.

I'd suspect Ferrari simply left them in place after once removing an engine and finding out how flexible the chassis was. You can just see them with a jack under the middle of the chassis trying to line up the top bolts....

 

Lee N  The ultimate unstressed engine mountings are probably the hoseclipped in Smallblocks in Sprinters, I look at them - and the general lack of diagonals on a Sprinter chassis - and shake my head in amazement. But they work - and very well too.



#38 Doug Nye

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Posted 29 May 2022 - 05:28

I really doubt that the 'struts' mentioned above were part of the original Lancia structure. There are no mounts for such top longerons visible in either pic - start of this thread and repeated subsequently - of the original 1954-55 Lancia D50 installation.

 

DCN



#39 GregThomas

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Posted 29 May 2022 - 07:20

I stand corrected. It appears that the lower of the two tubes each side which pierce the bulkhead - and are welded to it - has had a plug welded in to serve as the attatchment point for the strut.  As this plug is not there in the top pic - but the tube end is visible - it has to be a later fitting.

I'd still like to have been an observer when they put an engine back in though.



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#40 doc knutsen

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Posted 29 May 2022 - 09:32

There is one practical problem with a semi - stressed engine design which is getting the engine back in after removal. With a fully stressed layout like a Cosworth DFV the engine is bolted onto the chassis by four bolts and only has to line up there.

 

With a semi stressed layout the engine has to fit the chassis front and back where the intervening frame may have distorted. with use.

So every engine change requires possibly force flexing the chassis to fit the engine holes back in line.

 

Maybe this happened on the Lancia based cas as tehy went multiple races and led Ferrari to give up on the idea.

Many moons ago my brother purchased a Saracen FFord from the factory sans engine, and it was left to me to fit the engine to the chassis once the car made it to this country. It was designed to utilise the Ford Kent engine as a semi-load-bearing chassis member, and getting everything lined up was a bit of a time-consuming operation. In its first race, it broke a part of the engine block bellhousing mounting flange clean off.. That engine block was never meant to take the twisting forces of a chassis. In its favour, it did look nice, in black with gold pinstriping, as per the JPS of the day.