What is the average percentage loss of flywheel hp to rwhp. The formula we use at work is up to 20% loss with a manual transmission and up to 40% with an automatic. Of course these are over the road rigs, RV's, cement mixers, etc. I have personally dynoed a 600hp diesel with manual trans and had 545 @ the wheels. Acceptible hp is 480. We use the dyno quite extensively for t-shooting low power complanits. Notice I used the term up to. I know every vehicle is different and weight can play a factor. Just curious on an average percentage number for our F150's. Also, these percentages that we use stay the same whether its a dodge with a 5.9 diesel/ automatic or a cement mixer with a 14 liter/ automatic. Sscully or Neal, any ideas. Once again, just curious.Thanks fellas!

 

Average for our trucks seem to be about 27%. 185-195RWHP for the 5.4L stock. Generally in automotive transmissions, manuals are in the 12-18% range and automatics 20-30% losses.

 

HI!... The 4r70-w has a 65h.p drivetrain loss, the 4R100 has a 69H.P drivetrain loss. This has been proven on SUPERCHIP's "EDDY" current dyno.

 

Thanks, I got your reply on "the other one."