tigris

Assuming you have enough traction/suspension setup, What power/weight ratio will get you into 10's or 9's? Would 5 lbs to 1 hp be enough run solid nines? Thanks

tigris

Any help on this? Thanks

Colonel

My power (HP, not RWHP) to weight ratio when running 9.8s was ~4.85:1.

Red01Chevy

i think it would depend on your setup. i mean it would take more hp for a m6 then a A3 or A4 (if a A4 could handle it)gear is also a factor

v8-7

Colonel,,, how did you come up with those numbers.
Flywheel HP to the wieght of your car with driver or without?
-or-
Rwhp to the weight of your car with or without driver?
--did you use torque for any figures?

Curious to know becuase my car is 2800 without driver, 2950 with, and 570rwhp, so maybe 630 flywheel hp? Whats the % of loss from flywheel to the rears? i know it can depend on the dyno,, but whats the average% loss?

Using flywheel hp and wieght without driver my ratio is 4.44lbs to 1 hp
That sound correct? If so,,,

Colonel

As I said, "HP, not RWHP".

The weight I used was the actual raceweight (that means, with driver, helmet, laptop, gas, change in the center console, dirt, etc....)

The drivetrain loss (which actually IS NOT a fixed percentage) is *generally* about 83-88% (again, if you want to *call* it a percentage) with an auto and about 80-85% with a manual.

If we have 570 RWHP and assume 88% then that gives you 648 HP at the crank. 2950 lb/648 HP= 4.55:1

rhamm1320

I dont think its directly proportional (spelling?). A 50 hp increase in a grocery getter will make a huge difference, but a 50 hp increase in a pro stock will not change the et near as much.

Here is the easy way to play around with the numbers without all the math - plus its free.

http://www.virtualengine2000.com/ProgramDownload.htm