jarednut4ever

iTrader: (13)

I have a 2003 Z71 Ex cab, 5.3 3.73 posi. Long tubes no cats true dual, custom tune,custom intake, ud pulley, elec. fans. I have 18 inch wheels with 31.5 tall tires. My question is why are my 1/4 mile times so slow compared to others. I know I have a strong motor cause I can beat all 5.3 liters around here and also raced 4 Silverado SS's and beat them too. But I can only run a best of 15.40 @87.67 with a 2.4 60' with the 18inch wheels.Does climate and alltitude hurt that much. I live in kansas and our track is at 1850 elevation. And usually our DA is around 4500. Also stock LS1's run around 14.40-14.00 stock. Is that normal for a stock LS1. Let me know Thanks, Jared

kkd60

the problem is your 60ft time and your gearing. You are either spinning off the line, but I dont think you are, or you do not have enough gearing to get that weight moving fast enough. A stock ls-1 is usually around 13.2-13.8 depending on transmission and driver. I have a 31.9" tire and 4.56 gears and I cross the traps in third gear at 4400 rpm. With your gearing and tire size, you r crossing at 3500 in third gear or high in second gear. Change your gears or get a shorter tire.

litreddevil

iTrader: (4)

stall is what you need to move that heavy a$$ truck off the line

kkd60

stall will help alot also, but the gears will benefit you all the way down the track. I say get 28" slicks and a stall and you will be set.

speedy02

iTrader: (2)

I thank your DA is killing you... At the track i go to stock LS1's run 13.3-13.5 around 104+ MPH, But our track is sea level.. I can also pull 1.8 60' with my 3.73's and 255/50R16 M/T DR's and tci sf 3000... I thank you would benefit from a stall converter..

02sierraz71_5.3

iTrader: (2)

what is your 1/8th time and mph?
-a cam and stall would knock around .8-1 second off
-if you have traction problems launching use 4wd and as soon as your moving hit the 2wd button, floor it on the last green light
-there is a good chance the converter is locking as soon as you enter 3rd, thats around .1-.2
-you should be shifting around 6200 you have to manually shift it if the tune isnt right
-elevation is killing you also I bet you could get a 15.1 by running at sealevel

1slow01Z71

iTrader: (36)

YOU NEED A STALL. My heavy turd of a truck went from a 2.4 60ft at sea level to a 2.0-2.1 with a 3K stall. I wouldnt mess with gear too expensive since you have to do the front and rear the money is better spent elsewhere.

jarednut4ever

iTrader: (13)

It runs a 10.2-9.9 1/8. Not sure what mph it is. I have run with smaller tires I have 16 ich and have 255-50-16 drags. But I don't want to use them anymore. It is a hassle changing 4 tires just to race. Besides the tire change going from a 31.5 to a 26.1 inch only gains me 2-3 tenths. So I don't think gears is the entire problem. With the small 26.1 drags perfect traction I could only get a 2.29 60'. Only tenth difference. I think you guys are right I need a stall. Also I think DA hurts that much. My brother has a 2002 Trans Am WS6 and bone stock with 5000 miles he barely ran a 13. His 4 runs were 14.21, 14.08-13.99-and finally at 12:30 am he ran with no filter and got a 13.77 @ 101.34. It is an auto. The six speeds around here stock run slower then he does. There was a stock 02 Camaro SS 6 speed with drag radials power shifting and dumping the clutch @ 4k running a 1.8 something 60' and only running a 14.40 @98.50 mph. So it might just be our altitude.

TravisH

iTrader: (1)

My 60' when down from a 2.418 to a 2.083 with my stall. It was one of the best mods Ive done. And my overall 1/4 time dropped from a 16.047 to a 15.154 with just the stall, tranny, nelson tune(over the hypertech) and gutted cats.

Like I said in your other post, a tr220 would be a good cam, but 02sierraz71_5.3 is runnin one a little bigger, and I think it is trever1t who is running a 224/224

F8L Z71

You're DA is what kills you and the fact you are too low in 3rd gear when crossing the traps.

When I was running N/A I generally never left 2nd gear. I would just wind it out. Stock it is quite easy to do but once you start getting mid 90s mph you have to rev pretty high. My Best N/A times were in the 14.30s@97mph with a best of 14.29@96.8 and that was with the stuff you listed, a Synergy Motorsports 226/.535/112 cam, Yant TT300 stall, great tuning and a lil weight reduction. I went from 2.4 60's to 2.0 60s with stock 3.73s and stock 265/75/16 tires.

For max ET I owuld stall it up in 4wd and right after the launch switch to 2wd. Put the gear selector from 3rd into 2nd right after it shifts into 2nd gear and just hold it in 2nd till the end of the 1/4. You really dont make great power in the upper rpm range stock BUT the gearing makes up for it or at least it did for me. I was always slower if I let it shift into 3rd.