39 replies to this topic

[Bluehair]

Let's see here... McLaren lacking reliability in the early part of the season. It seems like they tried that last year and they had to give Mika a vacation to help him cope. What's it going to take this year, surviving a plane crash? I'm all about hearing a 20,000rpm v-10 though. TFF1, I couldn't agree more about your "forced extraction" theory. I'm sure the exhaust is being pulled out, but it raises some questions: Is there somewhere else it could be routed that would have even more of this effect? Is the horsepower gained more beneficial than concentrating on exhaust-aided downforce?

[GunStar]

Question, was the Honda a 2 of 4 stroke engine? That would make a BIG difference.

I've heard rumors of a twin crank system required to get these phenomenal RPM. I personnal disagree, but who knows what "invention" will be required to get this high. One thing the engine designers can do to bring the rpm up is to reduce the stroke. This required either making a longer engine, or reducing the displacement. Now, if I could get another 500 rpm, but only with a 2.9L engine...only the reliability and power output would be in question. If it passed the 3Ls ability, then they may go for it.

[Larry Connell]

Originally posted by Ray Bell
Honda's venture into skyrocket revs in the sixties was a 50cc engine, I think a twin, and it redlined at about 18,000, IIHBCI&RC. And it was more like 1964 than 1960.
A long way from the 18,500 of a modern 3-litre V10!

About the same time Suzuki had developed, but never raced, a 3 cylinder 50cc two stroke (1 ci/cyl) that was spinning in the 18 k range . It needed a gazillion speed gearbox for powerband was very, very narrow. It was about this time that the FIM yelled stop and limited the 50cc bikes to a single cylinder.

[bleakuzs]

If one were to increase the piston diameter, you would also have to make the block bigger and heavier to accomodate the larger pistons.

Yet, what would the stroke abe shortened to? I would be willing to bet that by having too short a stroke the torque curve would be absolutely destroyed.

[marion5drsn]

Limiting factor of engine speed; the piston speed is the first and most important factor in turning the crank at higher rpm. Piston speeds at this time are right around 5,000 feet per minute.
As has been stated by other people before the old limit on piston speed was around 4,000 feet per minute. (All “steel engines”) Even if they allowed any material to be used in the manufacture of the rods and pistons would it result in a large increase in rpm? Doubtful, as the strokes of the new engines are so short that they must be reaching a point of no improvement. One of the dead ends the many people miss in the use of ceramics and other materials is that you just can’t increase the temperature of the engines without a lot of consideration in the sealing of the piston rings with oil and just how are you going to lubricate the engine? It’s the simple things that get you!
One must remember that even if you double the diameter of the cylinder (Impossible) the valve circumference only increases by twice as much as previously. That is the circumference/diameter of the piston is directly proportionate to the circumference/diameter of the valve. But the area of the piston is increasing by the square of the radius of the cylinder. Since the valve circumference is the breathing portion of the cylinder only just so much improvement can be made. Even if some manufacturer reduces the stroke to 40% of the bore the result at the valve is only the 10% from the previous 50% b/s ratio.
Example 6.000” piston has valve diameters of 1.980”
3.000” piston has valve diameters of .990”
Also remember that a 6.000” piston is not twice as big as 3.000” piston, it is four times as large in area. The area of the cylinder is the part that influences the cubic capacity of the engine. This is one of the cases that simple arithmetic kills good ideas!
# 2, The next thing that is difficult to keep in mind is the fact that the valve stem sticking down into the port is round and about as unstreamlined as one can make it. If anyone can get gases to flow around this obstruction at better than the 60% the speed of sound then they had better go to work at Ilmor. Altho the use of modern theories of sound such as Finite-Amplitude Wave Motion have done wonders in the output of F1 engines it is still up against the Mach number in the port passages. This may also be the reason that five valves are not the great thing that many people believe as now you have three valve stems in the path of the incoming gases instead of just two.
M. L. Anderson

[marion5drsn]

Camshafts and balance; A brochure given at the L.A.
Auto show from Toyota on the MR2 had a line drawing on the front of the upper portion of the MR2 engine. Especially the camshaft and valve area. The part of the drawing that was unusual was the areas that depicted extra lobes that do not appear to be a function of the valve or timing of any part of the engine! I am curious as to what is their purpose. As a camshaft is only a mechanism to move the valve it would not appear to have any purpose in this endeavor. It makes me wonder as to the balance of the camshaft longitudinally out of balance.
Since all camshafts are out of balance to a small degree, is it enough to be concerned that a manufacturer to provide extra “lobes” to balance the camshaft? This four-cylinder engine only turns 6,400 rpm (Camshaft 3,200 rpm). Possibly this is used in the manufacture of the cams?
If this out of balance condition (?) exists in such a small engine turning a small amount of rpm is it likely that the cams in a V-10 turning at 10,000 rpm are contributing an out of balance to a larger degree?
Since the four cams in the V-10s are running at almost 10,000 rpm are there multiple vibrations of a lower order being set up as they in conjunction with other vibrations causing damage to the engine or to the electronics.
Camshafts are of a small diameter and would not seem to cause a lot of vibration, but then again all this messing around with bank angles and so forth doesn’t seem to alleviate the problem of balance and vibration either. M. L. Anderson

[Manson]

Could Toyota be using these extra lobe cams in different engines? Each engine uses different lobes? Seems a little simple but you never know.

How much torsional flex is there in a cam? I've heard the cams twist like plastacine at high rpms.

[kike]

Redline, I think the 20k rev limit is not because a combustion problem. The real problem is at that speed the valve is choked, so no more air is able to come in the cylinder. Combustion speeds up with revs, and its efficiency is higher with the microturbulence generated in the valve, which is proportional to the mean piston speed.

[Melbourne Park]

Are there any statistics available as to the cause of current F1 engine failures?

Hopefully these do not include chassis stress related failures, but I guess that's not so straightforward to deduce ...

[kike]

Danger, I disagree with you completly, because the limit revs in any engine is the inlet choked. Of course you tell us that on engines without valves, at that revs the inlet is choked. Perhaps I don´t understand your explanation, or I haven´t expressed myself. The choked section is at any part between the inlet valve and its seat, when the opening. A lot of parameters are used to measure it, i.e. mean inlet mach number. Volumetric efficiency for design is one of the aplications. The short slot you talk about, is one reason for the diminish of the volumetric efficiency, and so the torque; power from determinate revs begin getting lower because the increase of revs doesn´t beat the decrease of torque, making unuseful increasing revs. But the top revs is marked by incapacity of admiting more air flow caused by an inlet choked section.
It`s my point but no experience available, sure you`ve got more, and wishing to learn.

[marion5drsn]

Reversing the engine rotation is not much of a problem as the only real problem is the camshaft needing the opposite lobe rotation. I don’t know if it would be an easy task if the cam lobes are asymmetrical as I believe they are. I don’t for sure know about engines made in Europe as to rotational aircraft engines but Allison V-12 1710 cubic inch aircraft engines were made reversible to make the plane more maneuverable. This in the P-38 Lockheed Lightning fighter plane. These used an idler wheel to reverse the accessories section. If all you wanted was to reverse the direction of the propeller (Output shaft) a simple idler wheel is all that is needed. If one is interested in reversing engine in flight they should study engines in Zeppelins as some were manufactured with in flight change of rotation, some needing only 7 seconds to do this.
In ordinary engines of the garden variety the distributor needs a reverse rotation on the distributor gear to make sure the oil pump does not pump the wrong way. The distributor rotation is wired the opposite, which is not much of a problem. Coolant pumps are only a problem if the vanes are helical which would make the pump direct the coolant in the wrong direction but as long as the vanes are straight away from center (radial) it is of no importance. The firing order of the engine remains the same but the engine is numbered from the opposite side of the engine.
Boat engines at one time I believe were used with opposite rotation but I haven’t heard much of this of late.
Corvair flat six engines were used with opposite rotation in the aftermarket when the engine was transferred to the mid engine style.
The only reason an engine turns the way it does is due to the original method of hand cranking the engine If you pass a hand crank to a right-handed man he will almost invariably turn it to the right (Clockwise from the front of the engine). I have often wondered how many left-handed men incurred broken arms and wrists and fingers/thumbs due to reversed cranking of the engine. Many people know if the spark was not ******** when hand cranking an engine it will back fire and reverse the engine rotation and break the afore mentioned body parts. No wonder that Delco-Remy pioneered the first practical electrical starter. M. L. Anderson

[kike]

Danger, your first paragraph agree with my explanation. When no more lift gives better cylinder filling, is because the choke is reached. In this sense with valves removed, the choked section is properly the valve seat diameter, since then no more air is able to entry. Agree with you in all the rest, nice explaining. Thanks.

[Melbourne Park]

Originally posted by DangerMouse

I think F1 engines are at this point where even larger valves just aren’t effectively doing anything any more –

I guess (ignoring whether its physically possable) that you could not have a kind of valve in the side of the cylinder as well, rather than just the head ... the valve numbers are restricted, I suppose their position is also ...

[Melbourne Park]

[QUOTE]Originally posted by Top Fuel F1
[QUOTE]

Assuming a F1 V10 with a bore of 94mm, you only have a stroke of 43.23mm. These side orientated valves would have to be elongated to give enough area. As well the dwell would have to be extreme to avoid a collision with the piston unless some sliding valve gate scheme was invented. Also you could have many very small valves operarating in the conventional way, which would create a tremendious octopus of plumbing and a host of valve mechanisms.

Rgds;[p][Edited by Top Fuel F1 on 02-20-2001] [/QUOTE]

OK... I agree the plumbing's a nightmare, from a conventional view at least. But if a different valve did work, then I'd guess a V10 would be necessary ... you could then go for a more compact V4 or V6 with a longer stroke if the restriction on air was less of an issue.

I guess if someone did invent something, I suppose they would get rid of the poppet valves on the top first anyway, and just have the whole top a single valve. The intake and exhaust could be made to share the same valve, could it not ??? Wouldn't that help with getting more into the cylinder if that is the bottleneck to performance???

[Melbourne Park]

Besides the sleeve valve idea, what about having an arrangement where the four valves per cylinder act as four intake valves and then four exhaust valves? An arrangement could operate before the valves to switch the appropriate flows from exhaust to intake. If this worked, would it not remove the current bottleneck of the intakes capacity and speed to fill in time?

[Melbourne Park]

By the way, a 747 landed in Melbourne about an hour ago (that's 3:30 pm Wednesday, Melbourne time) with the first load of Grand Prix equipment. Only 6 more 747s carrying Grand prix machinery are due, most of them arrive this Saturday.

I drove on the track almost by accident a few days ago, the Grand Stand looks good, the portable two story corporate buildings that have been placed on the main straight alongside the permanent Pits stands are very impressive. My 8 year old knows the Ferrari pit area well: he has a roller blade hockey weekly program, and they skate indoors in the area occupied Ferrari and McLaren. No doubt the area will soon look very different, but in from an eight year old's point of view, the toilets there would be just the same ...

[Melbourne Park]

Originally posted by desmo
It's too late for this year I'm sure, but remind me next year and let's see if we can't seruptitously plant some clandestine surveillance devices in the premises prior to the circus' arrival at Melbourne for 2002. I've got to get to the bottom of this firing order mystery!;)

Yes what a good idea. There are quite a few metal pillars and the ceiling is quite high: maybe 12 to 15 feet. I would not think it difficult to place a spy cam at the top of one of the pillars if not on the ceiling.

Maybe connect a video cam onto a notebook and a mobile phone to the net: we could all watch it live ...

Just send me the money for the spy cam please, plain notes would be best.

However I think since they set up new walls between the area where my son plays roller blade hockey, they may well spot such a cam. And I bet those teams have better surveillance techniques than the FBI have been using lately, at least according to the Russians that is ...

[30ft penguin]

JFYI, last year the digital TV channel I watch ("Bernievision") showed rpm numbers during the race and during qualifying (not all the time, but very often). The only engine with rpm around 18.000 was the Jaguar (Ford) engine, they ran at just about 18.000 during qualifying. McLaren and Ferrari went as high as 17.500-17.600 during qualifying and to about 17.300-17.400 during the race. At Suzuka, both MS' Ferrari and MH' McLaren were obviously running a higher rev limit for the race, both peaked at about 17.800 there, but most of the time shifted at about 17.500-17.600.

They measured the rpm via the engine sound and mentioned during one of the early season races that they had shown the data they got to several teams, and while of course those teams did not mention any exact numbers, they said that the data was "pretty close to the truth". So I guess these numbers are indeed somewhat reliable.

So 20.000 rpm for 2001 would be quite a large step for Ilmor, over 2.000 rpm more than last season. I cannot really imagine they would do that, because (as seen last year) dropping out in several of the early races can mean that some important championship points are missing when it comes to the last races of the season.

[Melbourne Park]

I read concerning the new 111 degree Renualt V10 that their engine has some type of electronic vavle arrangement is is supposed to rev to 20,000 RPM. Maybe the Ilmore rumour wasn't an Ilmore rumour???

[bleakuzs]

No fv*king way that Illmore are breaking 20k. Their engine pitch was essentially the same as last years.

Also, if the teams were running to 20k, they could make about 900-925, only having to acheive around 230 ft-lbs of torque.

There is also a reason why no teams would run an engine backwards, what would there be to gain? NOTHING! It would also mean that parts would have to be designed to accomodate the counter rotation, thus making things heavier and slower, so power would drop off slightly, for what?

Reading this post has convinced me that most of you are overstepping your boundaries of knowledge and are simply making blank speculation about idiodic theories of fantasy.

Yet it is very entertaining.

[bleakuzs]

to answer your question, one very simple theory, THE RIGHT HAND RULE.

When you reverse the rotation of any mass, the inertia forces are also changed, gyroscopes are good examples. Meaning that if you rotate something counterclockwise parallel to yourself, it will move toward you, wereas if it were rotating clockwise it would move away due to the inertia. (Same reason cars go counterclockwise on ovals, to keep from turning into the wall.)

When engine parts are designed, they are designed to reciprocate in one direction, not two. Not only would the internals have to be designed to rotate in both directions, but ll the ancillaries as well. Reversign the cooling system would surely be a good way to destroy a modern F1 engine. Also the alternator, oil pump, and scavenging pumps are designed to maximize in one flow direction, much less two!

Desmo, it's simple logistics, the engine may not weigh more, but the ancillaries would.

[Engineguy]

Originally posted by Halfwitt
I would think this almost inconsequencial compared to other cornering or suspension forces, and this would be if the driver floored it. Is my argument flawed, or is this 10kg worthwhile?

Not to mention that on any given road racing course there are nearly as many corners where a particular rotation direction would have the opposite effect, diluting any benefit to virtually nil. On the other hand, if I were doing a "clean sheet" design of engine for the IRL (CCW ovals only), might as well pick the advantagous rotation. Of course this discussion reminds me of the "Big Bang" theory (crap, says I) that went around GP bikes and CART a few years ago.

[Engineguy]

Originally posted by Halfwitt
... Anything he used others viewed as an advantage, and so eventually eveyone moved back to the normal firing order...

I'm not sure I want to debate this subject... I don't follow bike racing that closely. But between the opinions of friends that do, and my own engineering sense, I'd pretty well written the subject off as a phychological effect (plecebo?) as you touched on above. With all the variables involved (constant updating and development of engines AND tires between AND during the season), I wonder if anyone conclusively proved the tire wear part of it in proper back to back blind testing (keeping the rider's head out of the equation).

[Engineguy]

Originally posted by Richard Border
DM

....and an extra 250cc. There's no substaute for cubic CCs.

Gee, ya think that helps?

[Engineguy]

Originally posted by DangerMouse
Not at that capacity, the Dukes are still 15-20 BHP behind the best 750 fours.

To make it even power-wise, fours would have to be limited to about 700cc or less.

Ducati certainly do not have a power advantage - they have a traction and corner speed advantage both thanks to the packaging and power characteristics of the V-Twin engine.

WAY too many variables here to be insist that there is some advantage coming from something as obscure and controversial as powerpulse-induced micro-slippage of the tires. More likely the old "area under the torque curve" vs. peak HP battle.

[Engineguy]

Originally posted by DangerMouse
Measure the area under the torque curve you'll find that the engine that makes most power also has the greatest area.

Measure the area under the torque curve of an R1 over a 996 Duke, the R1 pi$$es on it from such a height it's not even funny - hence the rules limiting a 4 to 750CCs, A leading Honda engineer was even quoted as saying 700cc fours against 1000cc Twins is about fair with regards to power!

The Twins have not got a "capacity advantage" in WSB!

You don't understand the issue of area under torque curve vs PEAK HP. Example:

Two racers racing; each time they shift their RPMs drop by 2000, from 16000 to 14000.

Racer A has a cam that gives him a flat torque curve of 100ft-lb from 14000 to 16000.

Racer B has a cam that gives him 85ft-lb at 14000 and the curve goes linear up to 105ft-lb at 16000 RPM.

Racer B's engine supplier brags that he's developing 5% more peak horsepower. That's why B bought from him.

Unfortunatly for B, they don't have any races on superspeedway ovals. Racer A is gonna smoke him on the road courses they race on.

Area under A's torque curve is... 100 x 2000 = 200,000

Area under B's curve is ((85+105)/2) x 2000 = 190,000

Breaking it down to 500RPM intervals to see what happens:

Right after the shift A is applying 100ft-lb vs B's 85ft-lbs. A goes from 14000 to 14500 in 0.4 sec while B takes 0.5 sec. From 14500 to 15000 A takes 0.45 vs B's 0.5 sec. From 15000 to to 15500 takes both of them 0.5 sec. From 15500 to 16000 takes A 0.5 sec and B 0.4 sec. Total time in that gear was 1.85 sec for A and 1.90 sec for B. This happens 50 times a lap.

Racer A dominates the season. Racer B is pissed at his engine supplier and stupidly looks for one who can give him more PEAK HP next year.


And I don't understand that you say 996 is not more than 750.

[Engineguy]

Originally posted by slipstream
Honda decided not use a 996 twin design for it's new Four stroke GP bike , instead they will use 1000 V-5 design. The Honda engineers said that a 996cc would not have enough power plus it has slower engine pick-up compared to the 500 cc two strokes.

I can't imagine it seriously took very long to make that decision, in the absence of a displacement advantage gifted by the rulebook. Are the 500cc two-strokes going to still be legal in GP or is it going four-stroke only? The V5 is a neat idea; three small cylinders wide vs four bigger cylinders wide for an inline4. Probably as narrow as a V4 too (two bigger cylinders plus bank offset), and more revs too.

[GrooveJet]

Volkswagen have a V5 engine available (in europe anyway) in the 150 BHP VW Golf V5. There is also a Golf V6 (replaces the previous model VR6). It is a 3.0 V6 (200 BHP) with a narrow angle vee 15 degrees I think, with a common head which covers both vees.

[Engineguy]

Originally posted by Richard Border

...designing a V-10 and cutting it in half!
[/B]

Honda is already prepared for MM's announcement of a displacement reduction to 2.0L in F1 to prevent tires from killing marshalls.

Do any of you know for sure if pneumatic valve closure is legal in the four-stroke GP bikes? Or if 500cc two-strokes are still legal? Or where I might find out?

[Engineguy]

Stop it!

[desmo]

Strange. First I get about 10 copies of my last post, OK mouse problem fixed, and then as I go back to delete all the duplicate posts I end up deleting 2/3 of the thread! Apologies to all whose posts were deleted inadvertently! Anyhoo,


Apparently the regulations for the class are yet to be published by the FIM, but
here's an article addressing the topic:

http://venus.13x.com...fourstrokes.htm

Wow, apparently you cannot post a link this long on this BB without the software becoming "helpful" and editing it into a dead link for you. Here's the full URL with a space in the middle.

http://venus.13x.com...ngworld/issues/ dec00/fourstrokes.htm

To visit the article I suppose you'll have to cut and paste the URL into your nav window and delete the space!

[Ali_G]

What the hell has happened to this thread.

For a start nearly 100 posts have gone missing.

And it was started by me yet it says started by Bluehair.

Niall

[Ali_G]

Oh sorry about the last post. I just saw what Desmo said.

Niall

[DangerMouse]

Where are my posts?!

[Halfwitt]

Originally posted by DangerMouse
Where are my posts?!

At either end of your washing line??

[Isamu]

HAH HAH


:lol:

[desmo]

DM- sorry, see my post above. I have no idea how it happened.

[Ray Bell]

Ordered a new mouse?

[desmo]

No I just disassembled it, cleaned it and put it back together, then it worked. I wish repairing cars worked that way!

[Melbourne Park]

Originally posted by desmo
No I just disassembled it, cleaned it and put it back together, then it worked. I wish repairing cars worked that way!

Their getting more like optical mice, best not to try that approach with them either.