stav hitting 6600rpm!!!!/dyno

FS5 · 16-04-2008, 08:14 PM

i was reading through the thread that just got closed,so please no dyno arguments.
but...on the topic of how high should the rpm limit be set /verses peak hp rpm i wouldn't mind knowing .
lets just say stav set his limiter @ 6500.can a dyno measure what hp/torque he's pulling in 1st gear @6500rpm?
now,if stav changes to 2nd after hitting 6500 in 1st = X rpm in second,can a dyno read how much hp/torque he is now getting in 2nd gear.

what i'm getting at is even though a cars peak hp/ torque is dropping off @high rpm ,can a dyno measure wether you better off holding 1st gear longer to keep the cars momentom going rather than changing gears just after the power peaks?
i hope this makes sense..

Walkinshaw · 16-04-2008, 08:38 PM

Yes.

Undertake a dyno run in 3rd gear. Then interpolate the shift point RPM drops onto the graph.

Easy

**Falcon Coupe** · 16-04-2008, 08:39 PM

Quote:

Originally Posted by Walkinshaw

Yes.

Undertake a dyno run in 3rd gear. Then interpolate the shift point RPM drops onto the graph.

Easy

Agreed, no guess work.

The engine makes max power at the same rpm regardless of what gear it's in.

ratter · 16-04-2008, 09:04 PM

Gear ratio changes between gears and where the torque peaks, can also be a consideration,

when changing gears you will want the revs to fall around your torque peak so it will pull harder in the next gear, the torque can also be measured to see what rpm this would occur at, so by over revving engine past the peak horsepower can sometimes make the car quicker because it may make it closer to the peak torque

Sox · 17-04-2008, 07:24 AM

Quote:

Originally Posted by ratter

Gear ratio changes between gears and where the torque peaks, can also be a consideration,

when changing gears you will want the revs to fall around your torque peak so it will pull harder in the next gear, the torque can also be measured to see what rpm this would occur at, so by over revving engine past the peak horsepower can sometimes make the car quicker because it may make it closer to the peak torque

Exactly. In most cases (as I said in that 'other' thread) the limiter can be set 200-300rpm higher than the actual power peak, so you can rev a frag beyond the power peak if needed.

Rick.