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A visual example of the 90 degree crank drawback.
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A visual example of the 90 degree crank drawback.
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Ignorance leads to confidence more often than knowledge does.
Nah, I'm not leaving myself out of the ignorant brigade....at times.
Nah, I'm not leaving myself out of the ignorant brigade....at times.
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Re: A visual example of the 90 degree crank drawback.
As someone that like things to be orderly and sound smooth I liked the idea of flat crank V8s before ever working on one.
Then when I went to work at HPD on the Indy engine, they had both flat and 90 degree cranks.
I was disappointed to see that the power differences were not what one might expect.
In some ways better, in some ways worse.
Vibration, the flat crank was worse.
When I worked at Bryants crankshafts, in the early years, we were the first company that could make a really good billet crank. Racers from Pro Stock, NASCAR, Nitro etc all tried flat cranks, very few tried more than 1.
Then when I went to work at HPD on the Indy engine, they had both flat and 90 degree cranks.
I was disappointed to see that the power differences were not what one might expect.
In some ways better, in some ways worse.
Vibration, the flat crank was worse.
When I worked at Bryants crankshafts, in the early years, we were the first company that could make a really good billet crank. Racers from Pro Stock, NASCAR, Nitro etc all tried flat cranks, very few tried more than 1.
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Re: A visual example of the 90 degree crank drawback.
Wish there was some videos of those testsSchmidtMotorWorks wrote: ↑Sat Oct 01, 2022 12:47 am As someone that like things to be orderly and sound smooth I liked the idea of flat crank V8s before ever working on one.
Then when I went to work at HPD on the Indy engine, they had both flat and 90 degree cranks.
I was disappointed to see that the power differences were not what one might expect.
In some ways better, in some ways worse.
Vibration, the flat crank was worse.
When I worked at Bryants crankshafts, in the early years, we were the first company that could make a really good billet crank. Racers from Pro Stock, NASCAR, Nitro etc all tried flat cranks, very few tried more than 1.
Re: A visual example of the 90 degree crank drawback.
So there should be some cheap wrong cranks for hot rodders to buy now.
A balanced person dares to stagger, and modify ports bigger
Re: A visual example of the 90 degree crank drawback.
As with a lot of things automotive, the flat plane vs cross plane issue is another compromise ......
Smaller capacity V8s, predominantly those racing in the tighter regulated formulae where winning is down to the last 'enth', will almost always be 'flat'
Larger capacity V8s, where the rules are looser and there is generally more variety, will usually be 'cross'
And it's mostly a vibration thing ...... even Cosworth struggled with it in the early days with their puny little 3 litres pulling eight grand ...... particularly the very destructive out of imbalance, twice engine speed, secondary harmonic
Smaller capacity V8s, predominantly those racing in the tighter regulated formulae where winning is down to the last 'enth', will almost always be 'flat'
Larger capacity V8s, where the rules are looser and there is generally more variety, will usually be 'cross'
And it's mostly a vibration thing ...... even Cosworth struggled with it in the early days with their puny little 3 litres pulling eight grand ...... particularly the very destructive out of imbalance, twice engine speed, secondary harmonic
Re: A visual example of the 90 degree crank drawback.
Yer flat 8 cranks for flat 8 motors, at least then they can run some stroke length.SchmidtMotorWorks wrote: ↑Sat Oct 01, 2022 12:47 am As someone that like things to be orderly and sound smooth I liked the idea of flat crank V8s before ever working on one.
Then when I went to work at HPD on the Indy engine, they had both flat and 90 degree cranks.
I was disappointed to see that the power differences were not what one might expect.
In some ways better, in some ways worse.
Vibration, the flat crank was worse.
When I worked at Bryants crankshafts, in the early years, we were the first company that could make a really good billet crank. Racers from Pro Stock, NASCAR, Nitro etc all tried flat cranks, very few tried more than 1.
Although the flat 8's do sound....well...a bit flat.
Ignorance leads to confidence more often than knowledge does.
Nah, I'm not leaving myself out of the ignorant brigade....at times.
Nah, I'm not leaving myself out of the ignorant brigade....at times.
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Re: A visual example of the 90 degree crank drawback.
Honda is very secretive, and high security, during the hiring process I was never allowed to see the shop until my first day at work.
If you like engine dyno video of guys testing things with hope and cheer when there are good results, and "let's try this or that", you would be disappointed, it is nothing like that.
The dyno operators run double-blind tests, they execute a test plan and record the data, they are not informed of what change they are testing, as that could influence the process. Engineers were not allowed to go near the dyno rooms to avoid guesses by the operators about what was being tested.
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Re: A visual example of the 90 degree crank drawback.
Here is a good visualization of an 90* crank in the intake manifold with a common plenum:
https://www.facebook.com/watch/?v=303159527677911
(Converge CFD model from Roush-Yates)
I know the GM Engineers working on the IMSA / WEC / FIA Corvette C8R like the flat-plane crank because it pulls more evenly on the restrictors. They have BOP issues, but if they can fatten up things under the curve and make the BSFC better, it helps them in endurance racing.
https://www.facebook.com/watch/?v=303159527677911
(Converge CFD model from Roush-Yates)
I know the GM Engineers working on the IMSA / WEC / FIA Corvette C8R like the flat-plane crank because it pulls more evenly on the restrictors. They have BOP issues, but if they can fatten up things under the curve and make the BSFC better, it helps them in endurance racing.
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Re: A visual example of the 90 degree crank drawback.
Well I mean a flat plane cup motor or, prostock or top fuel.SchmidtMotorWorks wrote: ↑Sat Oct 01, 2022 12:01 pmHonda is very secretive, and high security, during the hiring process I was never allowed to see the shop until my first day at work.
If you like engine dyno video of guys testing things with hope and cheer when there are good results, and "let's try this or that", you would be disappointed, it is nothing like that.
The dyno operators run double-blind tests, they execute a test plan and record the data, they are not informed of what change they are testing, as that could influence the process. Engineers were not allowed to go near the dyno rooms to avoid guesses by the operators about what was being tested.
I'm sure the prostock and fuel guys made passes especially since the fuel guys aren't dynoing.
Re: A visual example of the 90 degree crank drawback.
I can tell some tips how to reduce weight from rotatin assembly It follows the cylinder head porting process, i mean the hole process not flow numbersBCjohnny wrote: ↑Sat Oct 01, 2022 3:51 am As with a lot of things automotive, the flat plane vs cross plane issue is another compromise ......
Smaller capacity V8s, predominantly those racing in the tighter regulated formulae where winning is down to the last 'enth', will almost always be 'flat'
Larger capacity V8s, where the rules are looser and there is generally more variety, will usually be 'cross'
And it's mostly a vibration thing ...... even Cosworth struggled with it in the early days with their puny little 3 litres pulling eight grand ...... particularly the very destructive out of imbalance, twice engine speed, secondary harmonic
Port and polish
A balanced person dares to stagger, and modify ports bigger
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Re: A visual example of the 90 degree crank drawback.
Well I mean a flat plane cup motor or, prostock or top fuel.englertracing wrote: ↑Sat Oct 01, 2022 2:12 pm Honda is very secretive, and high security, during the hiring process I was never allowed to see the shop until my first day at work.
If you like engine dyno video of guys testing things with hope and cheer when there are good results, and "let's try this or that", you would be disappointed, it is nothing like that.
The dyno operators run double-blind tests, they execute a test plan and record the data, they are not informed of what change they are testing, as that could influence the process. Engineers were not allowed to go near the dyno rooms to avoid guesses by the operators about what was being tested.
I'm sure the prostock and fuel guys made passes especially since the fuel guys aren't dynoing.
[/quote]
I guess there were only about 20 made in the 4 years I was there.
Those were the first 4 years, there were probably more after that.
I don't know if that kind of stuff gets sold on eBay or not.
I know of one nitro team that dyno tested.
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Re: A visual example of the 90 degree crank drawback.
They probably didn't abandon the idea because the "NVH concerns", it was a more "concrete" downside.
Paradigms often shift without the clutch -- https://www.youtube.com/watch?v=cxn-LxwsrnU
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Re: A visual example of the 90 degree crank drawback.
You must have loved it them doing it right.SchmidtMotorWorks wrote: ↑Sat Oct 01, 2022 12:01 pmHonda is very secretive, and high security, during the hiring process I was never allowed to see the shop until my first day at work.
If you like engine dyno video of guys testing things with hope and cheer when there are good results, and "let's try this or that", you would be disappointed, it is nothing like that.
The dyno operators run double-blind tests, they execute a test plan and record the data, they are not informed of what change they are testing, as that could influence the process. Engineers were not allowed to go near the dyno rooms to avoid guesses by the operators about what was being tested.
Paradigms often shift without the clutch -- https://www.youtube.com/watch?v=cxn-LxwsrnU
https://www.instagram.com/ptuomov/
Put Search Keywords Here
https://www.instagram.com/ptuomov/
Put Search Keywords Here
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Re: A visual example of the 90 degree crank drawback.
In the case of the IHRA Pro Stock applications which had strokes around 5.0 at the time, they were undrivable because of vibration.
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Re: A visual example of the 90 degree crank drawback.
Wow, I guess they had to try it, but anything over a pissant capacity that is being used in a weight sensitive environment is always going to be a disaster.SchmidtMotorWorks wrote: ↑Sun Oct 02, 2022 4:00 amIn the case of the IHRA Pro Stock applications which had strokes around 5.0 at the time, they were undrivable because of vibration.
Ignorance leads to confidence more often than knowledge does.
Nah, I'm not leaving myself out of the ignorant brigade....at times.
Nah, I'm not leaving myself out of the ignorant brigade....at times.