[enkeivette]

Some of you, namely Ben, will find this interesting. Motorhead on CF did an engine dyno with a 406, then immediately dropped it in his 81 and did a chassis dyno. He calculated a 23% drivetrain loss! With a modern manual trans.

So revise your calculations Ben.

[SeanPlunk]

Originally Posted by enkeivette

Some of you, namely Ben, will find this interesting. Motorhead on CF did an engine dyno with a 406, then immediately dropped it in his 81 and did a chassis dyno. He calculated a 23% drivetrain loss! With a modern manual trans.

So revise your calculations Ben.

What kind of dyno? A 23% loss is A LOT for a manual car...

[Vettezuki]

Originally Posted by enkeivette

Some of you, namely Ben, will find this interesting. Motorhead on CF did an engine dyno with a 406, then immediately dropped it in his 81 and did a chassis dyno. He calculated a 23% drivetrain loss! With a modern manual trans.

So revise your calculations Ben.

Same facility, operating temps, atmospheric conditions? A lot of params in there, to say nothing of differences in chassis dynos. It wouldn't surprise me if it's higher than a modern Vette, but 23% is massive. That would mean my engine is 480BHP.

[enkeivette]

Originally Posted by Vettezuki

Same facility, operating temps, atmospheric conditions? A lot of params in there, to say nothing of differences in chassis dynos. It wouldn't surprise me if it's higher than a modern Vette, but 23% is massive. That would mean my engine is 480BHP.

I argued with him about it first too, but he is including the full exhaust and the accessories in the 23%.

So it's not just 23% drivetrain loss, but including everything it's a 23% loss from gross power as he calls it. He's a smart guy, taught me a lot of what I know about tuning carbs. If it were anyone else I probably wouldn't buy it.

I can only image how much the autos are losing.

[enkeivette]

http://forums.corvetteforum.com/c3-t...ssis-dyno.html

[enkeivette]

Originally Posted by SeanPlunk

What kind of dyno? A 23% loss is A LOT for a manual car...

Don't know what kind of dyno.

[enkeivette]

I was really shocked to see this too. When the guys at DC dyno day were talking about a 25% drivetrain loss for their C3s I was definitely rolling my eyes. I guessed the usual 15% for manuals, maybe another 2 or 3% for the IRS.

[Vettezuki]

Originally Posted by enkeivette

I argued with him about it first too, but he is including the full exhaust and the accessories in the 23%.

So it's not just 23% drivetrain loss, but including everything it's a 23% loss from gross power as he calls it. He's a smart guy, taught me a lot of what I know about tuning carbs. If it were anyone else I probably wouldn't buy it.

I can only image how much the autos are losing.

You mean like accessories under load? (A/C on)? That'd change it a little but not a lot. Also, if he went from open headers on the engine dyno to stock exhaust on the chassis, or even just inserting an old fashioned cat, that's a potential killer. Still count me in the skeptical here.

[enkeivette]

Yeah, straight headers to full exhaust, not even a loud exhaust. I doubt the AC was on, don't even know if he has a compressor.

[enkeivette]

Wheel horsepower is all that really matters anyways. Who cares what your motor can do on a bench. My Neon is faster than a Miata because I have less loss, it is what it is. I just thought it was interesting.