i feel like a 14.05 for my truck is a little low but acording to this web page http://www.prestage.com/carmath/calc_etmph.asp i am prety close to where i should be. a whipple on a 6.0 is rated at 450fwhp by whipple, then add headers and exhaust and i should be near 500fwhp, the chart asks for rwhp so i enter 375hp(500-25%driveline loss) and a 5500lb truck.

all this and it says i should run a 14.25. i guess i am doing ok then. 375rwhp seems kind of low but it also seems like a 25% loss has been stated before, am i doing that right? and is the weight close?

 

That sounds about right. My dad's '99 2500HD 6.0 4*4 LT longbed..Whewww <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" /> weighs in at around 6000lbs with a camper shell and helper springs. Depending on your exact weight you are probably pretty close.

I always add a little to the rwhp if considering a converter because the average hp used is higher

John

 

i thought i had heard it was only 20% driveline loss?

 

I weighed in at 5050 last year. That was w/o driver and spare tire, but I also had some other junk in the truck at the time. Add 60+ for the whipple, driver weight, and any other extras you have to get close estimate to your trucks weight.

I've been using 20% drivetrain loss, but haven't got a clue what the real number is.

 

bigtex, you have an ext cab dont you? 5050 is less than i thought. i do have an LT that probably adds 100 or so + 170 for me than tire and whipple

5050+100+170+50+60=5430, how much gas did you have at the time and what about a trailer hitch?

time to recalculate 5430 weight, 500hp-20%=400rwhp puts me at 13.88. then i supose deduct a couple for the stall and i should be around 13.7

looks like i have a little work to do to be where i should be

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by crazyidiot4.8:
<strong>i thought i had heard it was only 20% driveline loss?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">But he's got a 4x4...so maybe a little more drivetrain loss??

 

I have a 1999 Excab Z71 5.3 LS

I do have a full size truck tool box. Had probably 1/4 tank of gas. I dont have elec seats or a hitch. It looks like your weight is pretty close to 5500.