43 replies to this topic

[Tmeranda]

Anyone have any information as to the firing order and crankshaft layout of modern F1- V-8's

[gary76]

Since all F1 engines are 90 degree V8's I would hazard a guess at; 1-8-3-6-4-5-2-7 the common order for a 'flat crank' V8.

[Tmeranda]

Thanks Gary,

Now just one more question. If the furthermost cylinder is No. 1 are the remaining cylinders on that bank 2,3,4 or 3,5,7? Manufacturers are not in agreement here.

[gary76]

The SAE std. is right hand cylinder bank numbered 1-2-3-4 with No 1 forward (ie No 4 at flywheel end). The left hand cylinder bank then numbered 5-6-7-8 with No 5 forward. It is also usual to have the right hand cylinder bank 'leading' the left hand cylinder bank. I say 'usual' since the are a number of manufactures who number cylinders from the flywheel end forwards, Renault and Nissan being among them.
May I suggest you obtain a copy of Heinz Heisler's book "Advanced Engine Technology" since it has a very good chapter on engine balance for those who need a basic understanding of the subject.
Gary

[Tmeranda]

Thanks again Gary,

I have the book on order.

By the way, Chevy has various ways on numbering their cylinders depending on engine size. Kind of makes you wonder.

[xf0001]

OK the firing order on Most F1 V8's is 1-5-3-7-4-8-2-6... hope this helps and it does follow that convention of cyls 1-4 on bank and 5-8 2nd bank... i understand there is a manufacturer who does not follow this convention but hey does it matter???

hope this helps....

[vvillium3]

xf0001,

Where did you obtain this info from? What are the advantages of this order? I thought the conventional (1-8)-(3-6)-(4-5)-(2-7) was the ideal flat plan firing order.

[vvillium3]

Also, I have read that Honda used an different firing order than everyone else until Monza in 2006. You could tell by the sound they were producing in relation to everyone else on the grid. I was at the USGP in 2006 (before Monza) and the Honda's sounded completely different.
What do you all think their firing order was???

[Greg Locock]

We built an I6 with the other firing order, and were sorely dissappointed with the result. Dyno results were lineball, (not surprising, at the time there was no real attempt to fine tune headers or intake lengths), and the difference in noise was subtle, albeit demonstrable. Basically it excited different torsional resonances, at different rpm. Toyota use that firing order in one of their engines.

So I think it likely that if you heard a significant difference in sound then it would have been due to other factors.

[vvillium3]

Still interested in this firing order (1-5)-(3-7)-(4-8)-(2-6). It seems like the standard order would be easier on the crank better by firing on opposite corners.

Greg,

Yeah, you are probably right about the sound. Different materials/layout and what not probably making the difference in sound. I still wonder what their different firing order was though. Did you attend a f1 race last year??? Honda had a very sweet and smooth sound compared to everyone else out there. Toyota was very similar too....

[xf0001]

Originally posted by vvillium3
xf0001,

Where did you obtain this info from? What are the advantages of this order? I thought the conventional (1-8)-(3-6)-(4-5)-(2-7) was the ideal flat plan firing order.

Were did i obtain this infor from.....Well i worked on one or more.... it is no secret really.... this has been the norm for a long time.... even mid 90's.......

[vvillium3]

xf0001,

I didn't realize you were a mechanic in F1. That is pretty cool, and thanks for sharing.
Do you know the reasons why they go with this firing order??? Also, do you know the first team to switch to this firing order???

[xf0001]

Originally posted by vvillium3
xf0001,

I didn't realize you were a mechanic in F1. That is pretty cool, and thanks for sharing.
Do you know the reasons why they go with this firing order??? Also, do you know the first team to switch to this firing order???

No I am not a mechanic.... I design Engines.......

[vvillium3]

Sorry, didn't mean to disrespect. Pretty sweet job then if you are working on F1 motors. Who do you work for? Stressful job?

[xf0001]

Non Taken..... One of the majors.......
Enjoy

[phantom II]

Mmmmm. There are only two majors and since you live in England it must be McLaren. Who do you like best, Hamilton or Alonso? Well I don't like either, I like Raikenen but I don't like Ferrari. I've been a McLaren fan since the Bruce and Denny show. I just like a mans character over all else and Kimi wins hands down over the McLaren bums. Trouble is, Kimi is supported by Todt and Montezemolo. I like Dennis but he supports Hamilton and Alanso. Why aren't there decent people in F1 like Bruce and Denny anymore? I have to bite the bullet and hope the Mclarens take one another out at the first turn and thereby allowing the best and most decent man to win the championship. Failing that, could I bribe you to pull the spark plug leads off the Mercedes engines on their last pit stops?

Anyway, back to V8s. I notice you didn't chime in on the W9 thread, thank God, but one member suggested that the best configuration for the most efficient engine is a 120' V6. Since you design F1 V8s you may know what might make street V8s fuel efficient.
There is no NA V6 that produces 505 HP and 500ft/lbs of torque, gets 30mp(US)g at 80mph and weighs 430lbs like the 7 liter LS 7 Corvette engine. 80% of the torque is available at 1700rpm and remains nearly flat to the max. The sleeves on each bank are one iron casting with no water jacketing between the pots. The LS2 has just been replaced by the LS3 in the 08 base Corvette. They upped the HP to 436 from 405 and raised city and highway MPG by one. The LS3 has 6.2 liters and a single cam in block without VVT and gets the same gas mileage as the 7 liter LS7 of the same architecture. How do they accomplish this? A F430 engine weighs more, revs 1200 rpm more, has no torque, is top heavy cost a bundle and gets 14 MPG at 80mph and has little room for improvement. The F430 weighs the same as the Vette and the Vette thrashes the Ferrari on every count. Which approach do you prefer? All German V8s sold here pay a gas guzzler tax. No GM car pays a gas guzzler tax and Cadillac DOHC V8s get better gas mileage than all its European competition. What does GM know that they don't?
Gasoline will be $100 per barrel real soon permanently so the Chevy approach seems to be the correct one.
If current F1 cars could only take on 40 gallons of petrol one time for the 200 mile GP and the lap times may not be less than 97% of the qualifying time, what engine design would you come up with?

Originally posted by xf0001
Non Taken..... One of the majors.......
Enjoy

[imaginesix]

Originally posted by phantom II
Mmmmm. There are only two majors and since you live in England it must be McLaren.

Aha! So clearly that is the Ferrari's firing order he gave us!

Oh no wait, their firing order is Stepney-1-5-3-7-4-8-2-6...

I kill me.

[DOHC]

Originally posted by phantom II
Gasoline will be $100 per barrel real soon permanently so the Chevy approach seems to be the correct one.

Given that the gas price in Europe is already close to $300 to the barrel, Chevy's achievement is all the more remarkable. Or could it be that Europeans make a lot more money?

[phantom II]

What I think is extra ordinary, is that this engine has been improved every year since its release in 96. It comes in all different sizes and installed in a variety of vehicles including cast iron versions in trucks. There are a bunch of really knowledgeable engine gurus here who speak of engines lovingly. I have cut and pasted tons of material from their contributions and filed it some where in my documents. There are all kinds of things that will reduce emissions and get more MPG and power but no company achieves this with a single cam pushrod V8. When it is dismantled, it hardly looks different from very early engines. What is GM doing right now to improve the LS3 that has just started production? It will have more HP and run cleaner for 09 for sure. I bet it will have 450hp but unlike all its competion, it will get better gas mileage. Forgive me for belaboring the point but I would think that engine guys would be as intrigued with these things as I am for the reasons I've stated.
I know exactly how economical this engine is because I have owned 4 variants of it so far, the latest being a LS 7 which got 32 MPG a couple of weeks ago. It will pull real hard from 500rpm to 7000. You only use first and 3rd in town and over 20mpg in town is normal.
My son has a F430 and I now exactly how much gas that thing uses. It is quite pathetic really in this day and age. The lower the rpm, the more gas it uses. Drive behind it when it accelerates and you will suffocate with that rotten egg smell, where as, if you are behind my car, you don't smell anything, well that's if you ignore the burning rubber. I think an LS7 transplant would make a F430 a much better car, but that's just me.

Originally posted by DOHC


Given that the gas price in Europe is already close to $300 to the barrel, Chevy's achievement is all the more remarkable. Or could it be that Europeans make a lot more money?

[cheapracer]

Originally posted by vvillium3
Sorry, didn't mean to disrespect. Pretty sweet job then if you are working on F1 motors. Who do you work for? Stressful job?

..and whats wrong with being a mechanic?

I'm a mechanic.

[cheapracer]

Originally posted by phantom II

My son has a F430 and I now exactly how much gas that thing uses. It is quite pathetic really in this day and age. The lower the rpm, the more gas it uses. Drive behind it when it accelerates and you will suffocate with that rotten egg smell, where as, if you are behind my car, you don't smell anything, well that's if you ignore the burning rubber. I think an LS7 transplant would make a F430 a much better car, but that's just me.

Do it, show the world, f... the purists.

I have put a few Holden reds (186 ci) in things, a Bimmer and 240Z come to mind - much better cars after (a few years back).

[gary76]

Getting back to the nub of the thread. A little research has revealed for a 'flat crank' V8 engine firing orders:
1965 Coventry Climax: 1-8-2-7-4-5-3-6
Ford Cosworth DFV: 1-8-3-6-4-5-2-7
xf0001 has given for the 2007 F1 engine a 'typical' firing order of: 1-5-3-7-4-8-2-6
He, rightly, states that they would all follow the convention of cyls. 1 to 4 on A bank and cyls. 5 to 8 on B bank. Does it matter? No, I would hazard a guess that it has something to do with the torsional loads imparted into the crankshaft.

[vvillium3]

cheapracer,

No, nothing wrong with a mechanic. I thought I may have offended he by assuming he was one.

gary76,

I was thinking about the torsional loads as well. It seems that the 1-5-3-7-4-8-2-6 that xf001 suggested would be the worse out of all the others. So what is there to be gained in this order??? This would be a good project. Build a flat plane V8, test one way and then switch plugs locations and camshafts on one bank and see what the difference would be.....

[xf0001]

Originally posted by vvillium3
cheapracer,
No, nothing wrong with a mechanic. I thought I may have offended he by assuming he was one.
gary76,
I was thinking about the torsional loads as well. It seems that the 1-5-3-7-4-8-2-6 that xf001 suggested would be the worse out of all the others. So what is there to be gained in this order??? This would be a good project. Build a flat plane V8, test one way and then switch plugs locations and camshafts on one bank and see what the difference would be.....

Yep I agree nothing wrong with a Mechanic... and NO i was not offended... i have many a friend who are. And for that a very skilled Bunch too without them we would not have Jobs and vice versa...
Sure torsionally the loading is different the firing orders that Gary wrote for the Coventry Climax engines and the DFV are what they are... It is normal practice for a development group to play with firing order as part of a development exercise naturally this will be validating models that have shown various advantages / disadvantages. Maybe some team/s are using the other firing order and torsionally thier drivetrain may have a different frequency. Everybody has different ways of doing things. We all find different things work for 1 and not for the other thats why we all go and test.

[phantom II]

I read some where that JJ His had to come up with a very different TC for his wide Renault V10 because the engine was quite fragile. The firing order varied through out the rev range while TC was active and the ignition was not cut like the other teams did. With the advent of the new rule that requires the engine to last, would there be a firing order that would be more beneficial to longetivity in favor of power particularly when TC is active?
If the torque pulses move from front to back or visa versa like the CC and DFV V8s as opposed to random pulses found on today's engines, I would imagine that the torsional loads are reduced considerably especially in the case of the DFV engine where it goes from 1 to 8 and then from 7 to 1. They must have established the ideal firing order for both power and life by now.
Firing orders sometimes consider intake and exhaust pulses to be more important than torsional considerations. Also cooling reasons require that sequential firings are placed as far from one another as possible.
Chevy changed their LS7 firing order to stabilize idle and vibration but got tons more power even more than if they went to a flat plane crank with the benefit of improved NVH . 18726543 is now used on the new Chevy SBC NASCAR engine mostly to make it last longer due to harmonics improvement with a slight HP gain. (Carburetor)
Swapping #7 and #4 cylinders in the firing order eliminated fuel distribution and heat problems caused by cylinders #5 and #7 firing in succession. There are gains in smog control for street use also.
I am sure that these properties are taken into account in the design of a F1 V8 also.

Originally posted by gary76
Getting back to the nub of the thread. A little research has revealed for a 'flat crank' V8 engine firing orders:
1965 Coventry Climax: 1-8-2-7-4-5-3-6
Ford Cosworth DFV: 1-8-3-6-4-5-2-7
xf0001 has given for the 2007 F1 engine a 'typical' firing order of: 1-5-3-7-4-8-2-6
He, rightly, states that they would all follow the convention of cyls. 1 to 4 on A bank and cyls. 5 to 8 on B bank. Does it matter? No, I would hazard a guess that it has something to do with the torsional loads imparted into the crankshaft.

[vvillium3]

There is a brief paper floating around in the tech articles about different firing orders in the Renault. It is not technical at all, but is a good overview of what is going on. This is with the V-10 of course.
I am sure F1 teams trade off power for more vibration, as long as it is not effecting the longevity of the engine. So I agree with you 100% Phantom. It just seems odd to me that they F1 is firing the cylinders that share the same rod journal at the same time as opposed to the cross pattern of the DFV and Ferrari. Equaling out the forces across the crank seems optimal to me. But that is why I am not an engine designer, just a follower.
Either way, I love the sound of the flat plane V-8. Nothing like having two 4-cylinders behind you whaling away....

xf0001,

How did you work your way up to where you are at? Sounds like it could be a very rewarding job if all goes the right way.

[Almag]

Re: LSx vs other V8s,

There's no magic in why the Corvette turns decent fuel economy on an EPA drive cycle. The car itself is low drag, has reasonably small frontal area, tires has reasonably low rolling resistance... but most significant of all, the LSx is always accompanied with extremely tall gearing.

In years past, GM even employed a 1st-4th skip-shift in the gearbox in order to beat the gas guzzler tax...

[phantom II]

There is one little detail that I can't comprehend and that is how 20 000 rpm effects the thinking of ignition timing over 7000 to 9000 rpm pushrod V8s and 14000 rpm DFV V8s. The best V8 sound I have ever heard is the 7 liter Ford engine in Gurney and Foyt's GT 40. It had 180' headers and a tiny flywheel. It had a higher pitch than the P333 Ferrari which also had a gorgeous sound all its own. The Ford didnt sound like a big V8 at all. The 7 liter C6 R Corvette sounds awful and so do the GT 2 F430 Ferraris on the track. The V10s sounded better than the V8s in F1. If you go to Speed TV.com , you can download a V10 sound to your phone.

Originally posted by vvillium3
There is a brief paper floating around in the tech articles about different firing orders in the Renault. It is not technical at all, but is a good overview of what is going on. This is with the V-10 of course.
I am sure F1 teams trade off power for more vibration, as long as it is not effecting the longevity of the engine. So I agree with you 100% Phantom. It just seems odd to me that they F1 is firing the cylinders that share the same rod journal at the same time as opposed to the cross pattern of the DFV and Ferrari. Equaling out the forces across the crank seems optimal to me. But that is why I am not an engine designer, just a follower.
Either way, I love the sound of the flat plane V-8. Nothing like having two 4-cylinders behind you whaling away....

xf0001,

How did you work your way up to where you are at? Sounds like it could be a very rewarding job if all goes the right way.

[phantom II]

Quite right. I failed to mention that at 80mph, the LS 7 is turning at 1600 rpm in 6th with 4.2 gears. It is very easy to short shift and the torque of the engine calls for it. Ist to 4th is a bit much, but going for 3rd still gives me over 20 in town and it doesnt change even if I use second. The only reason I dont use second is because it is extra work. My wife's V8 Oldsmobile gets 28 mpg when I drive it on the highway and 18 locally. Also pretty low RPMs. A friend of mine has a C6 Z06 and instead of comparing lap times, we compare fuel economy numbers and he gets on it more than I do. Even if you let the RPMs get up there, it still gives good numbers. Hard driving is not that bad either, better than a F430 or a S 2000. If you use the 500 hp, it will cost you but you seldom use it. Most big cars now use very tall gearing but dont get anywhere near LSx engines mileage. Automatic LS1s in Camaros and GTOs do better than 6 speeds but they weigh 4000 lbs compared to the Vettes at 3100 lbs.

Originally posted by Almag
Re: LSx vs other V8s,

There's no magic in why the Corvette turns decent fuel economy on an EPA drive cycle. The car itself is low drag, has reasonably small frontal area, tires has reasonably low rolling resistance... but most significant of all, the LSx is always accompanied with extremely tall gearing.

In years past, GM even employed a 1st-4th skip-shift in the gearbox in order to beat the gas guzzler tax...

[vvillium3]

Phantom II,

I bet that GT40 sounded great. That is one car I have always wanted to hear in life. Did you mean Ferrari 333SP that was used in IMPSA racing? I saw one of those this last summer at a local Ferrari gathering. What an amazing sounding car. The owner was real cool. He let me look around the car and ask a ton of questions. But you know what car sounded better at that meet was a Porsche GT. Talk about a full filling sound when the Porsche GT, Challenge Stradale, and 333SP were circulating around the track at the same time. Makes you want to have enough money to own them all.
I Agree V10's sound beautiful. I have seen V10 F1 car's in action before. It almost too high pitched, but wonderful.... It's a toss up to which one sounds better though.
I also wonder about the timing on these high revving motors? Image how sensitive they are to it, and how much advance they require. Maybe xf0001 can give us some insight....

[desmo]

From memory, recent F1 engines have been timed at ~50 degrees BTDC I think.

[phantom II]

F330p I think raced at that time. Weber IDA carburetors and lower RPMs made the difference in sound and those occasional missed gear changes were amazing. You have to go to historic races to hear those sounds anymore. The Ford had a 4 speed and it took a long time to shift and a long time between shifts. It could do 100mph in first and 240mph in 4th and you could hear it wailing thru the night. (Music from the Big Pink)
That big engine came to a stop between shifts but sure sounded sweet when it blipped back up to the correct RPm. WaaaaaaaaayiiiiiBLAH....waaaaaaaaaaaayiii. An essential activity for Dan and AJ to do in order to preserve the clutch for the next 23 hours which they led. I am trying to attach a file with no success. Kaka.The 3 distinct sounds of the Porsche 917, Ferrari and Ford allowed you to identify the cars before you made eye contact. Those were the days when men were men and girls knew it.

Originally posted by vvillium3
Phantom II,

I bet that GT40 sounded great. That is one car I have always wanted to hear in life. Did you mean Ferrari 333SP that was used in IMPSA racing? I saw one of those this last summer at a local Ferrari gathering. What an amazing sounding car. The owner was real cool. He let me look around the car and ask a ton of questions. But you know what car sounded better at that meet was a Porsche GT. Talk about a full filling sound when the Porsche GT, Challenge Stradale, and 333SP were circulating around the track at the same time. Makes you want to have enough money to own them all.
I Agree V10's sound beautiful. I have seen V10 F1 car's in action before. It almost too high pitched, but wonderful.... It's a toss up to which one sounds better though.
I also wonder about the timing on these high revving motors? Image how sensitive they are to it, and how much advance they require. Maybe xf0001 can give us some insight....

[Tmeranda]

Originally posted by desmo
From memory, recent F1 engines have been timed at ~50 degrees BTDC I think.

How can that be true. That would mean the plug is firing while the piston isn't even half way thru the compression stroke. That some advance!

[vvillium3]

When the power stroke only lasts 0.0126 seconds, you have to start the burn a little early.

[Halfwitt]

I think some F1 engine manufacturers might be happy with as little as 50 degrees of advance, especially with the big bores and high speeds used.

[Tmeranda]

Originally posted by vvillium3
When the power stroke only lasts 0.0126 seconds, you have to start the burn a little early.

See your point. BTW how did you calculate.0126?

[Greg Locock]

18000 rpm=300 rev/s, power stroke=1/2 rev=1/2*1/300=.0016 s

diameter of bore is say 0.1 m, 50 degrees BTDC is say 0.8 ms, so flame front speed is .05/.8*1000, about 62 m/s

seems a bit slow, where did I go wrong?

[vvillium3]

Stupid math, thats how I came to that number. Sorry, brain fart. So much for all of that college math

[DOHC]

Originally posted by Greg Locock
so flame front speed is .05/.8*1000, about 62 m/s

seems a bit slow

62 m/s is a fast flame front speed, only possible thanks to turbulence. Without turbulence it might not even reach 10 m/s.

[zac510]

I had heard on this forum that the ignition advance was higher than 50, but that is by no means the truth.

Tmeranda, half way through the compression stroke would be 90 BTDC.

[Tmeranda]

Originally posted by zac510
I had heard on this forum that the ignition advance was higher than 50, but that is by no means the truth.

Tmeranda, half way through the compression stroke would be 90 BTDC.

Of course, my bad.

[McGuire]

With laminar combustion in a turbulent medium -- like air and gasoline in a cylinder -- the flame front propagates at the turbulent fluctuating velocity of the charge, more or less. (As the flame front advances forward, we are progessively burning through turbulent, pulsating, non-homogeneous zones of air/fuel-air/fuel-air/fuel.) So to a first approximation, combustion tends to occupy the same crankshaft duration regardless of engine speed. In other words, the quicker you pump it and squeeze it, the faster you can burn it. Also, if the plug is in the center of the chamber as in an F1 engine, the flame front advances in roughly most directions at once. So if the flame front's brush speed is n, the area of combustion is spreading across the chamber at around 2n. Meanwhile the trailing volume has been consumed by combustion and will neither support nor require a flame.

[wonk123]

Originally posted by phantom II
Quite right. I failed to mention that at 80mph, the LS 7 is turning at 1600 rpm in 6th with 4.2 gears. It is very easy to short shift and the torque of the engine calls for it. Ist to 4th is a bit much, but going for 3rd still gives me over 20 in town and it doesnt change even if I use second. The only reason I dont use second is because it is extra work. My wife's V8 Oldsmobile gets 28 mpg when I drive it on the highway and 18 locally. Also pretty low RPMs. A friend of mine has a C6 Z06 and instead of comparing lap times, we compare fuel economy numbers and he gets on it more than I do. Even if you let the RPMs get up there, it still gives good numbers. Hard driving is not that bad either, better than a F430 or a S 2000. If you use the 500 hp, it will cost you but you seldom use it. Most big cars now use very tall gearing but dont get anywhere near LSx engines mileage. Automatic LS1s in Camaros and GTOs do better than 6 speeds but they weigh 4000 lbs compared to the Vettes at 3100 lbs.

Not sure why they are such great engines. I owned a vx commodore 1700kg (3750lb) 225kw (300hp)
a 4 speed auto 3.08 final drive at 110km (around 70mph) it got around 31-32 mpg heaps bigger car
than a corvette. Interestingly because of the comp 10.1:1 to make it run on our crap standard fuel,
it was running very rich around 10.5:1 a/f and only 16 degrees total advance. Got and edit done (ls1edit)
and put a better exhaust on it, it made 230rwkw up from 185 rwkw and was getting 35mpg at 110km
it made heaps more mid range, which was more impressive than the increased top end, took it to western
sydney raceway and it ran 13.1 for the quarter as driven in off the street ( didnt even empty the boot)
(trunk for any Americans lol)
Have no idea what the top end was as it used to hit the 150mph (240km) speed limiter, this was removed during the edit, and it was at least 10mph quicker.

anyway 60s pushrod technology with a decent injection system, I cant wait till we get the ls3

[McGuire]

One significant edge the Gen III/Gen IV engine has over the old SBC, and various DOHC V8s, is lower internal friction. They have a natural advantage here and they have worked hard to maximize it.