Does anyone knows how much (rwhp) difference will I see dynoing my truck on the 28s (36" tall) and the stocks.

 

theres may variables but i ran 35's on the dyno my numbers are below
i think others put down 280-300+
its not so much the diameter but the weight

 

nelsons performance posted something a while back, and it was like 35s to 30s and it was 100hp difference.

 

where?

 

i second that. need to see this.

 

Yeah, I saw the same post. I think it is on ls1truck.

 

If I remember correctly there was a significant increase in measured HP by reducing tire diameter (and weight) on the roller dyno. I think it was something around 50hp but it's been a couple of years since Nelson posted that...

 

There is a pretty large difference, 50-100hp is typical.

 

I always wanted to test this on mine. I never had an extra set of wheels and tires when I'd go to the dyno. The 20's are heavy!

 

heres the link, it was 100hp....

http://www.ls1truck.com/forums/dynod...r-hp-dyno.html