I ran my truck at the track for the first time tonight. It’s a base Sierra with a 5.3 and the mods in my signature. The truck makes 300 whp and 334 tq. I ran back to back 15.6’s with no traction problems or anything. I expected more out of it than that but that’s all it would do. Is it the gear that holds it back so much? It’s got a 3:23. It does have 20’s on it but the 275/45 tires are actually shorter than stock I don’t think they slow it down. I know I stall would help. Or am I just expecting to much out of it?

 

My buddy ran 15.6's in his bone stock 99 5.3 rcsb, and it's no where near 300 rwhp. I'm not sure what's holding you back, i was think the 20's coupled w/ the 3.23's

 

how do you figure you ahve that much hp?

for the time you ran your hp isnt there if you go off the calculator
yes 20s will slow you down but not that much

 

with your mods I would say thats about right. What is your elevation? What was the DA when you ran? I have heavy *** mud tires on mine, I dont think I am near 300 rwhp, but probably close on the rwtq. I would say your gears are hurting you. What was your 60ft?

 

its was tuned on a dyno.

2.4 60' 15.6 @ 89 mph

i dunno on the elevation i am in memphis tn

 

2.4 60' seems kinda sluggish off the line. get some 4.10s to compensate for the 20"'s

 

man i ran 15.7 in my truck with just cat-back. and i'm 4wd. something has to be holding you back. you got HP Tuners...you sure you got the tune right? (not trying to insult you)

 

yea its not much off the line. and it shifts into 3rd and falls on its face almost right at the finish line

 

i checked for you, 540ft. I would say your gears for sure.

 

i didn't tune it, it was done by a performance shop.