what gear do most of you guys dyno your trucks in?? ive always done 2nd gears..6600 rpm in 3rd gear would be too much mph for me

 

3rd gear is 1:1 and should give the most accurate numbers. I've done one pull in 3rd to 5800 rpm. It was within 2hp of the 3 other pulls I did in 2nd.

 

They should be done in 3rd for the most accurate reading because of the 1:1 ratio but for many trucks, that does turn out to be too much mph...

 

on our mustang dyno from 5500 on up it seems to take for ever..so we just do them in 2nd on the trucks..

 

If you can remove your speed limiter then a 3rd gear is the way to go. At least on a Dodge I saw 15hp more in 3rd then in 2nd, but topping out at 6100rpm in 3rd it was at 122mph, which can lead to bad things like drive shafts over flexing if they aren't designed to handle those speeds.

 

Do whetever gear will keep your driveshaft and tranny in tact. 2nd gear will give you slightly lower numbers, but will keep your DS from going if you have the 1 piece.