I was wondering what you guys think... I think my truck is unusally slow for my mods. 99 ECSB 4x4 with an 05 5.3 w/ <10k miles. Mods in my sig. Race weight of ~5400lbs.

I ran the first run of the night on the 35s and got a 16.2.
The rest of the night I was on stock tires and fastest time was 16.18 @ 82...

Does anybody else think somethings wrong?

 

Do you have a gears? What pcm do you have? The 99's are known to not be very good. Were you spinning? Are you lifted? Going from 35s to stock tires and only dropping .02 sec something is going on.

What does the rest of your slip look like? You should at least be mid 15s at 5400 lbs.

 

4.56 gears, Nelson tune, no spin, 3" body lift.. The slips at home, I'll have to post it up later.

 

You have huge (stockers) tires and what gears? Oh, I see you have 4.56.. I'd say it's about right. What were your 60's? Your only go fasts are the headers, gears and tune...

 

Yeah, that's unuasually slow. Is it doing anything odd...like bogging in the high rpm? When's the last time you changed the fuel filter/plugs ect..? Throwing any codes? Tranny slipping?

Get that slip up when you can it will help.

 

It feels like it doesn't pull very hard in 3rd. No slippage though. I pulled plugs, they look good. I changed them when we put the motor in, bout 4-5k miles ago. Filter is maybe 3-4 months old. Not throwing any codes.

I don't notice any drivability issues under normal driving conditions though. I put it on a scanner and everything seems to be working properly. I'm wondering if something is wrong in my tune.

 

How olds the air filter?
What was the weather like when you ran?
What rpm are you shifting at? Is your tune updated to the mods you have? Do you still have the 99 pcm in there? On stock tires with 4.56s you are hitting 3rd around 68mph, so yea it should feel pretty slow. The MAIN thing that's throwing me is gaining pretty much nothing after swapping from 35's to stock wheels/tires.

Sorry for all the questions, but it may be something small as a bad plug or filter slowing you down. Just gotta take everything into consideration.

 

The filter was dirty.. I'm actually cleaning it now. Weather was about as good as it gets down here.. clear skies, pretty dry, ~mid 70s?.... Shifting around 57-5800. Tune is updated, except theres still a problem with the new gears and tires. Throwing an ABS light still, but retune is on its way. Still a 99 PCM... Do you think that could be an issue? I'm using my 99 fuel rail w/ 05 injectors and 99 throttle cable. I went through the traps around 3700-4000 in 3rd.

 

For reference here is a timeslip of my ecsb with 5.3, no cats, bullet muffler, stock gears, hypershitter, stock clutch fan, and a fram filter. I was around 800 lbs lighter than you though.

 

Yeah I was thinking at least mid 15s if not quicker is where I should be in stock tires.