Don Terrill’s Speed-Talk

Stan Weiss wrote: ↑Mon Nov 06, 2017 11:40 am So what did Chris say? From what I have heard the MoPar head is not as good as the GM head with the 10500 RPM rule. When there was unlimited RPM the MoPar's ran better but still had no advantage over the GM's.

Stan

That was essentially what Chris said. The Dodge head was designed with the TR in mind. They were short on runner volume (length) and they could make that up in the intake manifold. With the EFI and and rev limit it killed the dodge.

I wish I could find that interview.

Frankshaft wrote: ↑Mon Nov 06, 2017 12:59 pm No, from actually racing. Not using simiulators and assumptions, which come in handy don't get me wrong. But I know what's faster in the real world.

No comment on my cvt tranny reply to your question? It's a viable question, and a good example

Lets simplify this. Which Is Faster? - 600 hp @ 6200 RPM or 600 hp @ 6200 RPM

Based on the very limited information I have given I would say they are the same.

Now how about we talk about what differences in the engines would make one faster than the other.

I will start by wanting to know what peak torque was and at what RPM for each engine.

Stan

Stan, you posted BMEP earlier for the two combos, what is IMEP doing in each?
Which is more important?

Warp Speed wrote: ↑Mon Nov 06, 2017 1:41 pm Stan, you posted BMEP earlier for the two combos, what is IMEP doing in each?
Which is more important?

Jay,
People were asking for someone to post some numbers or dyno sheets or graphs. I took numbers from a 609 ci engine that made more than double the 600 HP. I shifted the torque curve and applied a correction fact and printout numbers for 6200 RPM then did the same for 7200. The BMEP numbers were useless but I did not take the time to remove them. So no I would not say any of those numbers are real.

Stan

Stan Weiss wrote: ↑Mon Nov 06, 2017 3:19 pm

Warp Speed wrote: ↑Mon Nov 06, 2017 1:41 pm Stan, you posted BMEP earlier for the two combos, what is IMEP doing in each?
Which is more important?

Jay,
People were asking for someone to post some numbers or dyno sheets or graphs. I took numbers from a 609 ci engine that made more than double the 600 HP. I shifted the torque curve and applied a correction fact and printout numbers for 6200 RPM then did the same for 7200. The BMEP numbers were useless but I did not take the time to remove them. So no I would not say any of those numbers are real.

Stan

So, you for all practical purposes, made up a bunch of numbers that you admit aren't real to win your argument?

No worse than observing something and making a false premise

Seems after reading all the posts in this thread, the best answer is:

"It depends"

...with a lean going to the added drivetrain flexibility of a wider power bandwidth (and possibly energy storage/momentum conservation.)

Am I completely wrong?

Frankshaft wrote: ↑Mon Nov 06, 2017 9:44 pm

Stan Weiss wrote: ↑Mon Nov 06, 2017 3:19 pm

Warp Speed wrote: ↑Mon Nov 06, 2017 1:41 pm Stan, you posted BMEP earlier for the two combos, what is IMEP doing in each?
Which is more important?

Jay,
People were asking for someone to post some numbers or dyno sheets or graphs. I took numbers from a 609 ci engine that made more than double the 600 HP. I shifted the torque curve and applied a correction fact and printout numbers for 6200 RPM then did the same for 7200. The BMEP numbers were useless but I did not take the time to remove them. So no I would not say any of those numbers are real.

Stan

So, you for all practical purposes, made up a bunch of numbers that you admit aren't real to win your argument?

L M A O

I never ran an simulations with that data. So I would have no idea what those curves would prove or not prove. The only numbers I used to do any calculations were 600 HP @ 6200 RPM and 600 HP @ 7200.

Stan

It should be clear that the peak number doesn't tell whole story. What the hp is at say 10% below peak hp rpm and say 10% after gives a better picture but ultimately if you want to compare you need an actual curve otherwise You can draw wrong conclusions.

Eg of the power curve noses over real quick it isn't good and the op mentions nothing about what happens after the peak. In the real world it's important.

But since the original question specified just peak power, the only assumption that provides a rational basis for discussion is that the postulated curves above and below the peak are otherwise proportionally identical. Therefore Stan's analysis is valid.

Up to 27 pages of bullshit now.

MadBill wrote: ↑Tue Nov 07, 2017 12:01 am But since the original question specified just peak power, the only assumption that provides a rational basis for discussion is that the postulated curves above and below the peak are otherwise proportionally identical. Therefore Stan's analysis is valid.

Of course, but in the real world it never works like that so people claim otherwise. Ultimately it means they don't understand and you can't reach maximum potential if you don't understand true cause and effect

Imagine if instead of dumbed down (averaged) inputs the dyno tells you that you used true inputs like torque per cylinder as function of crank angle and tried to work out the force output at the wheel tyre interface by time it all goes through the drivetrain accounting for all inertias, stiffness and damping.

Then compare electric motor vs ICE for same hp and rpm

digger wrote: ↑Tue Nov 07, 2017 1:06 am

MadBill wrote: ↑Tue Nov 07, 2017 12:01 am But since the original question specified just peak power, the only assumption that provides a rational basis for discussion is that the postulated curves above and below the peak are otherwise proportionally identical. Therefore Stan's analysis is valid.

Of course, but in the real world it never works like that so people claim otherwise. Ultimately it means they don't understand and you can't reach maximum potential if you don't understand true cause and effect

Exactly. If the only difference is the peak rpm and all else is proportional and set up properly then they are the same and that is all you can day with the information given......but that would be a very rare occurrence.

Normally you don't get to change rotating mass or transmission ratios or whatever to better match the engine rpm and are forced to get what you have working and that changes things a bit.....but there is no way to talk about theses things with just knowing the engine peak hp & rpm.

So out of all of these pages, no one has an engine with dyno sheet 600 HP at whatever RPM and someone else with a dyno sheet 600 HP engine at a higher/lower RPM peak?