About how much % of your hp is lost from the fly wheel to the Rear Wheels? i heard anything from 15-30 and i always thought it was around 20%.

 

in a manual its about 12-15% auto is 15-20%

 

It depends..

you cant put a # on it..

A TH400 is goin to lose alot more than a 700r4, and thats goin to be different than a 4l60e and a th350, or even a 2004r.

its 5%-30%

I seriously doubt our cars lose more than 15% max with an auto

I used to run a dyno, and realisticly.. people say its higher so you can say you have more power.

 

got to consider your drive shaft also, heard a carbon fiber drive shaft puts more to the ground.

 

If the '98's actually got the Vette's engine, rated @ 345HP, then my loss was 15% when stock. I dynoed a max of 293RWHP when stock. But, I had the sh!tty tires, thus the speedlimiter, so my runs ended at 5400RPM in 4th gear.

I've also heard:

- that the loss won't change (i.e., regardless of what I change in the engine I'd still only lose 52HP)
- that the loss varies with RPM and other factors.

It can't remain a constant percentage across mods. If you're not changing driveline/tranny parts, the loss isn't changing. Only real way to know is to pull the motor, strap it on an engine dyno, then put it back in the car and strap it on a regular dyno

$0.02

 

have fun doing that . I'll just stick with a dynojet.

 

A 4L60E is an electronically controlled 700r4, so if you equipped them with the same clutches, etc internally then they should perform the same.

 

Realistically, your drivetrain loss will go up as your engine torque output goes up. More torque will create more friction, more friction will create more heat, more heat means more power loss.

As your torque output increases, your car will climb through the RPM's faster than it did with less torque output. All stationary objects will resist change in movement or rotation, so the faster you want those objects to move or rotate (as is the case in acceleration) will require more power to do it, thus more drivetrain loss.

Now, once those objects are rotating at a constant speed they won't lose any more power than they did before since their rotating mass and inertia will remain the same; but people don't dyno at a constant speed. They dyno while their car is accelerating and this is why you will notice more drivetrain loss as your power output goes up.

 

Dont get picky, i was trying to prove a point. yes i know the 4l60e is electronic controlled, however they are not exactly the same otherwise.. but very very similiar to the point that you can say thats its just an updated electronic version.

 

what is the 41e60 or somthing like that??

 

4L60E is the auto trans that you dont have in your car

 

ive headrd multiply times that m6 15% and a4 18% loss

 

in addition to what 96fbirdA4 said, more torque is going to cause more flex in parts and that means more power loss untill the engine/parts stop acclerating

 

GM HIGH TECH PERFORMANCE Dynoed a STOCK LT1 Z28 accuretally rated at 285-HP with an auto and got 231-HP. That is 15% for an auto, but I'd LOVE TO SEE an engind DYNO Vs Rear wheel, as the engine power, Rated power and Rear Wheel power are alll different figures. Too bad the automotive industries aren't forced to rate at Wheel HP!