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-   -   DYNO THAT HELPS! OR DOES IT? (https://www.nopistons.com/race-prep-10/dyno-helps-does-56912/)

sohcmivec 01-31-2006 10:52 PM

guys...



lets say, from the dyno graph, my engine is stated to make peak power at 8000rpm, is that the exact or a must shift point during drag?...... or should i just redline all the way? is my concept wrong?



lets say, there's no dyno place and the nearest is 5000miles away, how can we determine when our engine is making peak power at which rpm?



is there such device? currently driving a stock 87 second gen....

Nospig 01-31-2006 11:17 PM

I think the new G TECH metres that you can download results to your pc give that info. Ive got the old g tech metre and got the same max hp reading that i got on the dyno .

tancred 02-03-2006 12:15 PM


Originally Posted by sohcmivec' post='798496' date='Jan 31 2006, 09:52 PM

guys...



lets say, from the dyno graph, my engine is stated to make peak power at 8000rpm, is that the exact or a must shift point during drag?...... or should i just redline all the way? is my concept wrong?





I dont know what the hell your trying to say...can you please try again.

teknics 02-03-2006 05:19 PM

wherever your peak power is means you're losing power once you pass that rpm.



most people try to shift around their power peak.



kevin.

sohcmivec 02-04-2006 02:45 AM

owh..how do we determine when is the peak power, by feeling? can it be done? or we do need some electrical gadgets?

teknics 02-04-2006 12:18 PM

you need to chart your hp level, aka use a dyno.



i guess some of those g-meter things migt be able to do it, and im sure there's some crazy math way to do it.



kevin.

jspecracer7 02-05-2006 03:44 PM

When shifting don't look at where you shift, but where you end up after you shift. You want to end up with the motor being above your peak torque number. If your max HP is at 8000 rpms and you shift at 8000 rpms BUT you fall BELOW your max torque....your going to be losing a lot of time. Shift until you reach the point in the next gear to get PAST max torque...which you'll proly need a dyno to find out.

sohcmivec 02-05-2006 10:42 PM

hm, what u mean is, lets say my engine's making peak power at 8000rpm,and whenever shift it will go down around 500rpm, thus in order for a perfect shift, i should shift at 8500rpm?

teknics 02-08-2006 05:12 PM

your car is going to drop more then 500rpm.



this is what i meant when i said "around" their power peaks.



what jspec tried to finish saying is this. get a dyno, from the graph you find where your peak torque number is.



when you shift the best scenario would be to shift from your peak hp and wind up a bit past where your peak torque is, otherwise youll lose a LOT of acceleration. however when you shift at your peak hp you might fall under your peak torque in the next gear. so its better to go past your peak hp so that at the beginning of the next gear youre at your peak torque so that acceleration continues at a good speed.



kevin.

sdminus 02-09-2006 04:28 PM

What You tried to say in the first post was correct but far more complicated than you think.



If you use a dyno and find peak power you can then take this figure and work out your shift points, You will also need to know the frontal drag coefficent, gear ratios, final drive ratio,exact tire height and a break down of the dyno run.



Basically the peak torque will move slightly due to these factors.



I have done this and it works. I managed a 12.62 @113mph on stock boost fd stock port with no fuel mods



Scott


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