Pray

iTrader: (7)

I just installed a cam and made my own 4" CAI for my truck and am going to add headers when they show up. The first time I dynoed my truck I had to do it in second because I didn't know there was a MPH limiter. Only got 260rw or so in second with Intake and Cat back. Now I have completely custom tuned it and want to get after cam results and then after exhaust results. I have always dynoed in the 1:1 gear. I was reading that with 3.42's and 31.7" tire it is a bad idea to use 1:1 due to tire speed. What do you all do? This is my first truck and don't want to jack it up. I really do want to use 3rd though.

Phantom

iTrader: (16)

You'll have some serious mph if you Dyno in third with that tire size and gear ratio

AndysC3

iTrader: (14)

third gear will go till about 150mph at 6000 rpm. That's kinda high for the tires and the driveshaft. If you do it just be careful

mhotrodscooter

iTrader: (13)

+1
Since your previous pull was in 2nd, Id run the same gear. Better comparison of hp gain.

Pray

iTrader: (7)

I have a 3.42 and 31.7" tall tires.

I didn't think about the drive shaft. I am used to Vette's and what not where all you are hitting is in the 130-140's and the car is designed for it.

I was going to do a second gear pull to get an apples to apples but wanted a 1:1 run to get the real numbers. The gear reduction seems to scew the numbers to the lower side.

Phantom

iTrader: (16)

Vettes also only have 26" or less tires. I wouldn't do a 3rd gear pull if I were you

Pray

iTrader: (7)

Seems like the consensus is to just do the pulls in Second. As long as that is the standard around here I will roll with it.

Jake99

iTrader: (5)

Id do 2 gear, that would give you a better idea of what you gained, iv never really cared that much about peak dyno numbers I just like to see how the power curve looks to help you along with your build. Im always afraid of my driveshaft coming apart.

AKlowriderZ71

iTrader: (22)

I've done 2nd, and 3rd. The numbers weren't very far off from each other, but the 3rd gear pull was a bit scary.

dmelvin

iTrader: (8)

There's several videos online about stock 2wd truck drive shafts coming apart around 120mph. If you're on the stock drive shaft, I'd definitely do a 2nd gear pull.