Why weren't flat engines experimented with more in F1? Why did Renault try a wacky 111° angle V instead?

All that has to do with the power train, gearbox, clutch, fuels and lubricants, etc. Generally the mechanical side of Formula One.
Tommy Cookers
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Re: Why weren't flat engines experimented with more in F1? Why did Renault try a wacky 111° angle V instead?

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those had of course 6 crankpins - so were '180 deg Vs'

Porsche had c.1962 F1 a 'boxer' flat-8 - it had 9 (10 really ?) main bearings
this was presumably dictated by the length resulting from the air cooling
after the success of the (4 main bearing) Ferrari 12s Tecno did a (sportscar ?) 2 litre '180 deg V' - it had 3 main bearings

saviour stivala
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Re: Why weren't flat engines experimented with more in F1? Why did Renault try a wacky 111° angle V instead?

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A correction to my post:- The 1955 Porsche 547 1.5-litre Flat-4 was not the only boxer configuration engine to have raced in F1, In fact in 1962 Porsche produced and raced in F1 their model 753 1.5-litre Flat 8 boxer configuration engine.
Given that a boxer configuration engine crankshaft is always going to be longer than a V-configuration engine including a Flat in V-configuration of 180 degrees with the same count of cylinders, for their model 753 1.5-litre flat-8 Porsche produced a terribly intricate steel forged crankshaft with 16 very thin/narrow cheeks, having a total of 9 incredibly narrow main bearings 20mm wide plus a tenth ball bearing at rear and with 8 con-rod bearings 22mm wide, this in an effort to keep the crank as short as possible.
Also the Jean-Jacques His designed 2001 R202 Renault 111 degrees V-10 first raced by Benetton B201 had both vibrations and stiffness weaknesses of which results in reliability and lack of power problems.

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Re: Why weren't flat engines experimented with more in F1? Why did Renault try a wacky 111° angle V instead?

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Tommy Cookers wrote:
Thu Dec 20, 2018 12:35 pm
those had of course 6 crankpins - so were '180 deg Vs'

Porsche had c.1962 F1 a 'boxer' flat-8 - it had 9 (10 really ?) main bearings
this was presumably dictated by the length resulting from the air cooling
after the success of the (4 main bearing) Ferrari 12s Tecno did a (sportscar ?) 2 litre '180 deg V' - it had 3 main bearings
Just this very minute I posted a correction with some more information. thanks for your attention to detail.

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Re: Why weren't flat engines experimented with more in F1? Why did Renault try a wacky 111° angle V instead?

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Flat engines, for racing are just heavy, high cog (because of the exhaust has to stick out on the bottom), aerodynamically difficult due to the intake sticking out away from the center line of the car, less stiff then an V shape block... all advantages they have slightly (less hight, good COG, easy plumbing) in road cars disappears when you change the sump system.

In the way the engine is mounted to the chassis and how it's used in a racing car as a structure, nothing beats a V. All the intakes and outlets are in the right angle, on the right sides and the structural stiffness is great.


I do like flat engines, I drive one myself (a BMW R1100) but it only works because there is a big sump under there, else a V (like a Guzzi) would be so much simpler.

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Re: Why weren't flat engines experimented with more in F1? Why did Renault try a wacky 111° angle V instead?

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Flat engines can be made to work with GE/diffusers, but it makes them vastly more complicated. Mercedes made one for the C291 in the 90s but it was only used for one season.

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Big Tea
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Re: Why weren't flat engines experimented with more in F1? Why did Renault try a wacky 111° angle V instead?

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Jolle wrote:
Thu Dec 20, 2018 2:34 pm
Flat engines, for racing are just heavy, high cog (because of the exhaust has to stick out on the bottom), aerodynamically difficult due to the intake sticking out away from the center line of the car, less stiff then an V shape block... all advantages they have slightly (less hight, good COG, easy plumbing) in road cars disappears when you change the sump system.

In the way the engine is mounted to the chassis and how it's used in a racing car as a structure, nothing beats a V. All the intakes and outlets are in the right angle, on the right sides and the structural stiffness is great.


I do like flat engines, I drive one myself (a BMW R1100) but it only works because there is a big sump under there, else a V (like a Guzzi) would be so much simpler.
I also ride a BMW R1100RS, and come maintenance time I notice the temperature on each cylinder is not maintained the same. Not a huge problem on a road vehicle, but I would imagine this would be more of a problem in F1.
So another disadvantage could be heat distribution?
One test is worth a thousand expert opinions

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Re: Why weren't flat engines experimented with more in F1? Why did Renault try a wacky 111° angle V instead?

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Big Tea wrote:
Thu Dec 20, 2018 6:17 pm
Jolle wrote:
Thu Dec 20, 2018 2:34 pm
Flat engines, for racing are just heavy, high cog (because of the exhaust has to stick out on the bottom), aerodynamically difficult due to the intake sticking out away from the center line of the car, less stiff then an V shape block... all advantages they have slightly (less hight, good COG, easy plumbing) in road cars disappears when you change the sump system.

In the way the engine is mounted to the chassis and how it's used in a racing car as a structure, nothing beats a V. All the intakes and outlets are in the right angle, on the right sides and the structural stiffness is great.


I do like flat engines, I drive one myself (a BMW R1100) but it only works because there is a big sump under there, else a V (like a Guzzi) would be so much simpler.
I also ride a BMW R1100RS, and come maintenance time I notice the temperature on each cylinder is not maintained the same. Not a huge problem on a road vehicle, but I would imagine this would be more of a problem in F1.
So another disadvantage could be heat distribution?
Good chance your throttlebody's are not in sync. With a bit of tube, two bottles and 5 minutes of work it should be fine.

Heat distribution should be equal as a V or even an inline. Whatever you are running, if one cylinder is leaner then the other, you have a problem....

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Re: Why weren't flat engines experimented with more in F1? Why did Renault try a wacky 111° angle V instead?

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Maritimer wrote:
Thu Dec 20, 2018 5:31 pm
Flat engines can be made to work with GE/diffusers, but it makes them vastly more complicated. Mercedes made one for the C291 in the 90s but it was only used for one season.

http://racem.org/wp-content/uploads/p ... 91-2.jpg
A superb clear nice photo. Were that photo was lifted from there are also superb front/top/side elevation very interesting print-outs of blueprints of the original technical general arrangement drawings.

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Re: Why weren't flat engines experimented with more in F1? Why did Renault try a wacky 111° angle V instead?

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saviour stivala wrote:
Thu Dec 20, 2018 8:38 pm
Maritimer wrote:
Thu Dec 20, 2018 5:31 pm
Flat engines can be made to work with GE/diffusers, but it makes them vastly more complicated. Mercedes made one for the C291 in the 90s but it was only used for one season.

http://racem.org/wp-content/uploads/p ... 91-2.jpg
A superb clear nice photo. Were that photo was lifted from there are also superb front/top/side elevation very interesting print-outs of blueprints of the original technical general arrangement drawings.
Even with this high tech flat racing engine you can spot the difficulties you would have design wise to put in on the back of a single seater instead in the back of a sports car. The intakes don’t look ideal and need a lot more space on the sides of the engine to create the right down flow. The exhaust are right in the area you want the bodywork as slim as possible plus there is an issue of installing radiators... didn’t Sauber put the cooling in the front?

saviour stivala
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Re: Why weren't flat engines experimented with more in F1? Why did Renault try a wacky 111° angle V instead?

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Jolle wrote:
Thu Dec 20, 2018 9:13 pm
saviour stivala wrote:
Thu Dec 20, 2018 8:38 pm
Maritimer wrote:
Thu Dec 20, 2018 5:31 pm
Flat engines can be made to work with GE/diffusers, but it makes them vastly more complicated. Mercedes made one for the C291 in the 90s but it was only used for one season.

http://racem.org/wp-content/uploads/p ... 91-2.jpg
A superb clear nice photo. Were that photo was lifted from there are also superb front/top/side elevation very interesting print-outs of blueprints of the original technical general arrangement drawings.
Even with this high tech flat racing engine you can spot the difficulties you would have design wise to put in on the back of a single seater instead in the back of a sports car. The intakes don’t look ideal and need a lot more space on the sides of the engine to create the right down flow. The exhaust are right in the area you want the bodywork as slim as possible plus there is an issue of installing radiators... didn’t Sauber put the cooling in the front?
This particular one was best once described as a “motorsports fail-the 1991 Mercedes-Benz C291”.
There actually was once a very successful flat-12 (180 degree V-12) raced in F1.

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Re: Why weren't flat engines experimented with more in F1? Why did Renault try a wacky 111° angle V instead?

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Jolle wrote:
Thu Dec 20, 2018 8:02 pm
Big Tea wrote:
Thu Dec 20, 2018 6:17 pm
Jolle wrote:
Thu Dec 20, 2018 2:34 pm
Flat engines, for racing are just heavy, high cog (because of the exhaust has to stick out on the bottom), aerodynamically difficult due to the intake sticking out away from the center line of the car, less stiff then an V shape block... all advantages they have slightly (less hight, good COG, easy plumbing) in road cars disappears when you change the sump system.

In the way the engine is mounted to the chassis and how it's used in a racing car as a structure, nothing beats a V. All the intakes and outlets are in the right angle, on the right sides and the structural stiffness is great.


I do like flat engines, I drive one myself (a BMW R1100) but it only works because there is a big sump under there, else a V (like a Guzzi) would be so much simpler.
I also ride a BMW R1100RS, and come maintenance time I notice the temperature on each cylinder is not maintained the same. Not a huge problem on a road vehicle, but I would imagine this would be more of a problem in F1.
So another disadvantage could be heat distribution?
Good chance your throttlebody's are not in sync. With a bit of tube, two bottles and 5 minutes of work it should be fine.

Heat distribution should be equal as a V or even an inline. Whatever you are running, if one cylinder is leaner then the other, you have a problem....
Sorry about the off topic....

Thats how I found the heat difference. I could not get things right, so stuck a probe on both sides so I was adjusting when they were the same. It is not just the head or pot, but the whole 'lump'
I don't know if it is metal density internally or air/oil being hotter in one part of its travel etc. Anyway, with the help of a heat gun I got them balanced, but I don't think it affects the idle, which is what I suffered with.
( Turned out to be a jet slightly oval. thanks. :D )

I could see this being a problem with 6 'pots' and the accuracy needed in F1 though. With all the metal around a V it must naturally be more stable, even if just when it is up to temperature.
One test is worth a thousand expert opinions

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Re: Why weren't flat engines experimented with more in F1? Why did Renault try a wacky 111° angle V instead?

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Maritimer wrote:
Thu Dec 20, 2018 5:31 pm
Flat engines can be made to work with GE/diffusers, but it makes them vastly more complicated. Mercedes made one for the C291 in the 90s but it was only used for one season.

http://racem.org/wp-content/uploads/p ... 91-2.jpg
wow that is wide!

Jolle
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Re: Why weren't flat engines experimented with more in F1? Why did Renault try a wacky 111° angle V instead?

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Big Tea wrote:
Thu Dec 20, 2018 9:34 pm
Jolle wrote:
Thu Dec 20, 2018 8:02 pm
Big Tea wrote:
Thu Dec 20, 2018 6:17 pm


I also ride a BMW R1100RS, and come maintenance time I notice the temperature on each cylinder is not maintained the same. Not a huge problem on a road vehicle, but I would imagine this would be more of a problem in F1.
So another disadvantage could be heat distribution?
Good chance your throttlebody's are not in sync. With a bit of tube, two bottles and 5 minutes of work it should be fine.

Heat distribution should be equal as a V or even an inline. Whatever you are running, if one cylinder is leaner then the other, you have a problem....
Sorry about the off topic....

Thats how I found the heat difference. I could not get things right, so stuck a probe on both sides so I was adjusting when they were the same. It is not just the head or pot, but the whole 'lump'
I don't know if it is metal density internally or air/oil being hotter in one part of its travel etc. Anyway, with the help of a heat gun I got them balanced, but I don't think it affects the idle, which is what I suffered with.
( Turned out to be a jet slightly oval. thanks. :D )

I could see this being a problem with 6 'pots' and the accuracy needed in F1 though. With all the metal around a V it must naturally be more stable, even if just when it is up to temperature.
"offtopic"... with the R1100 engine you can set/sync the idle speed on the left (the right is the "base" with the TBp sensor) at the back of the throttle body and then set right cable tension at the left one, at around 3000 rpm, with a vacuum tester. If you don't get too much false air due to worn out thottle bodies and your valves are in order (adjusted right and the same and well set spark plugs), temp should be more or less the same. if the temps are out of sync, with everything synced, then there is probably a bigger problem....
using heat to sync the two cylinders isn't the way to do it by the way ;)

but.. in racing engines this wouldn't be a problem. The BMW system is kinda old fashion after 25 years. Instead of (what they do with the BMW) putting all the sensors on one head and then manually sync the other one to match, these days and in racing there would just be two ride by wire throttle bodies, temp sensors on both, both their own injection mapping etc etc. It would be even better because there would be less interference from a near by heat "beaming" cylinder.

saviour stivala
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Re: Why weren't flat engines experimented with more in F1? Why did Renault try a wacky 111° angle V instead?

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Big Tea wrote:
Thu Dec 20, 2018 9:34 pm
Jolle wrote:
Thu Dec 20, 2018 8:02 pm
Big Tea wrote:
Thu Dec 20, 2018 6:17 pm


I also ride a BMW R1100RS, and come maintenance time I notice the temperature on each cylinder is not maintained the same. Not a huge problem on a road vehicle, but I would imagine this would be more of a problem in F1.
So another disadvantage could be heat distribution?
Good chance your throttlebody's are not in sync. With a bit of tube, two bottles and 5 minutes of work it should be fine.

Heat distribution should be equal as a V or even an inline. Whatever you are running, if one cylinder is leaner then the other, you have a problem....
Sorry about the off topic....

Thats how I found the heat difference. I could not get things right, so stuck a probe on both sides so I was adjusting when they were the same. It is not just the head or pot, but the whole 'lump'
I don't know if it is metal density internally or air/oil being hotter in one part of its travel etc. Anyway, with the help of a heat gun I got them balanced, but I don't think it affects the idle, which is what I suffered with.
( Turned out to be a jet slightly oval. thanks. :D )

I could see this being a problem with 6 'pots' and the accuracy needed in F1 though. With all the metal around a V it must naturally be more stable, even if just when it is up to temperature.
I personally doesn’t see anything wrong in going off-topic to make a point or share an experience, there is always something to learn. but I could easily figure out why some goes into allergic mode to others going off-topic from time to time.

mzso
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Re: Why weren't flat engines experimented with more in F1? Why did Renault try a wacky 111° angle V instead?

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DiogoBrand wrote:
Thu Dec 20, 2018 3:53 am
Just look it up, the 312T for example, was one of Ferrari's cars from the 70's that used a flat 12 engine.
You're right. They also won a few championships. Interesting that no-one ever really recalls the flat-12 engines.
Dr. Acula wrote:
Thu Dec 20, 2018 7:18 am
As far as i know in todays aero driven formula 1, they are considered as to wide. If you look at the back end of the side pods of the cars, you see this undercut coke bottle design. With a Boxer or Flat engine you could never made the undercut that extreme as we see it now with the V engines because simply the cylinderheads would take away some of the space needed to do that. The aerodynamic gain of a clean overflowed diffusor outweights simply the lower center of gravity.

Also if i remember correctly Renault had problems with the stiffnes of their 111° V10 engine. In many Formula cars the engine as a whole is a load bearing part. The Gearbox and so the rear suspension is connected to the chassis only via the engine. The 90° and smaller V-engines are generally stiff enough to carry these stresses without much additional strengthening or a sub frame. That's not the necessarily the case with a flat engine design. Which results in adding material to the engine to make it stiffer which also makes it heavier or using a subframe which also adds unwanted weight. If you look a bit through the hystory of Flat engines in racing, they are often considered as fairly heavy for its time and power output.

One further point is the plumming. You still need to get the air in at one side of the cylinder head and the exhaust out on the other side as some other people already pointed out. That means that at least one of them needs to be located under the cylinderhead which also means you can't mount the engine as low as you actually would want to because you need some space under the cylinderheads.
Good points.