Car is a 02 Z28 A4
Engine Mods
Freshly Built Ls1 bored to 3.920 (Yes I know Impossible right)
ls6 Block
Arp rod bolts
New Speed pro Flat top Pistons
Ls2 chain
Melling oil pump
FMS F14 low lift cam
799s Hand Ported by ZZRACER
Ls7 lifters
Vengeance Racing Ported fast 92
NW 92 throttle body
42lb green top injectors
Fast toys 98mm lid
Purolator Air Filter LOL
Tuned by JonCR96z
Jett hott long tubes into ory into a MagnaFlow 3"bullet stops at rear
Stock 342 rear
15inch weld rts wheels

On a dyno jet

I went into this knowing the bias ply hurt dyno numbers. Didn't have time to get my regular radials on stupid people at mechanic shop.

First pull it made 400 and like 380 tq. So we checked psi in the tires 22 psi. Tire said no more than 35psi in them so we went to 30psi.
Done another pull done 420hp and 390tq (WTF 20 rwhp from 8psi)

Last pull made 425 and almost 400tq.

With regular radials on there is no doubt in my mind it will make 440-450hp probably around 420tq.
It amazed me that it picked up that much from 8psi in the tire. Just goes to show every little thing comes into play while trying to make a number.

Moral of the story don't use bias plys on the dyno lol

 

20 hp from adding 8 psi is crazy. Is that tire/ wheel setup lighter by chance?

 

15x10 weld rts wheels with mickey Thompson 26" bias ply. Lighter as compared to what ?

It's significantly lighter than my stock 10 spokes and Mt drag radials I used on my first track day

 

Bias ply drag tires on the dyno is a great way to explode your tires. They aren't designed for that type of load.

 

Never heard of that one but thanks for the info

 

Yes compared to the stockers. Tires aside I've heard lighter wheels dyno better as well, that's why I asked

 

Yea no doubt they would. That wheel and a regular radials and I bet it would of done 440 plus

 

I've seen 50-70whp difference in back to back dyno's switching from big soft DR's to street tires.

 

Yea I had read that on Google that's why I wasn't heart broken when the numbers came out low
thanks for the reply

 

Good numbers but they would have been better if you would just listen to somebody. Lol

 

Ha ha ha I know I know I will dyno it again with radials the spring

 

Dyno video

 

exactly. its less rolling resistance on a street tire compared to a soft DR. Same principle with achieving better MPG (whatever that is) by having your tires borderline over inflated Vs a little too low.