Dyno question......
#1
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From: Port Tobacco, MD
Dyno question......
I know most dyno shops are going to dyno your car in 4th gear. The dyno is going to calculate RWHP via how fast the drum is accelerated. It appears that if you have a higher numerically gear ratio your going to dyno anywhere from 10-30rwhp lower depending on gear.
Basically:
a 2:73 rear will dyno higher than a 3.42 rear which will dyno higher than a 3.90 or a 4.10. What would happen if you took one of the big gear cars and dynoed in 5th vs fourth?
4th 1:1 with 3.27 = 3.27 FDR
5th .74:1 with 4.33 = 3.20 FDR
Would this remove the final drive ratio from a variable?
Phillip
Basically:
a 2:73 rear will dyno higher than a 3.42 rear which will dyno higher than a 3.90 or a 4.10. What would happen if you took one of the big gear cars and dynoed in 5th vs fourth?
4th 1:1 with 3.27 = 3.27 FDR
5th .74:1 with 4.33 = 3.20 FDR
Would this remove the final drive ratio from a variable?
Phillip
#2
Re: Dyno question......
I doubt it'd remove it from the equation. 4th gear is a direct pass through, 1:1, so it has less losses than 3rd or 5th gear. Dyno'ing in the direct drive gear is probably going to be the best bet.