Horsepower loss from engine to wheels?

[mrtleavitt]

Hey guys anyone ever dyno'd their engine and then dyno'd the whole truck? I'm wondering what the loss in horsepower would be through the drivetrain.

Engine H.P. vs Wheel H.P.

[r71f250]

This is somewhat difficult. You need to be more specific. What Transmission? What rear gear? What size wheels and tires? Drivetrain loss can be anywhere from 18-28%.

Example is my wheels and tires on my 71 weight close to 90lbs each, now that means just in wheel weight I have close to 200lbs. I have a C6 transmission. A C6 weighs around 230lbs. It has quite a bit of drivetrain loss just though the auto, but there is also torque multiplication through the converter.

Let us know more for an answer to you.

Blessings,
AMS

[papabug71]

All of my hot rod buddies tell me, for the worst case scenario, a 30% loss can be expected. It varies greatly tho.

[mrtleavitt]

-1969 F100 shortbed
-T19 manual tranny
-3.0 ring gear/ 9" rear end
-31 inch tires
-15" steel rims

I wanted to get a general idea for our trucks. I've seen the differences in newer mustangs and stuff but nothing ever for our trucks. I'm gonna dyno my truck in a few days. Edelbrock has dyno results with their Performer RPM 390 at about 450 hp. I have a very similar build with a 428 plus roller everything so I just wanted to get an idea of what the engnie might be at after seeing the hp at the wheels.

[r71f250]

With what you are describing I would guess between 22-24% drivetrain loss. Keep us update on your build sounds interesting. I am going to pull my 390 out here within the next 30 days and send it to FE Specialties, looking for about 370hp and 460ft lbs.

Blessings,
AMS