Went to the track for the first time Wednesday (yes, I played hookey. ). The good news: I beat 2 of the 3 people I was lined up against, and outperformed a Subaru WRX (it had a turbo, I checked). Bad news: My best was still absolutely rotten. Here are the gory details:

R/T: 0.860
60': 2.240
330: 6.186
1/8: 9.494
@MPH: 74.75
1000: 12.341
1/4: 14.823
@MPH: 89.98

This was launching in 4-HI. Launching in 2WD gave me 1/10 longer 60 ft., and 2/10 longer e.t.. Looking at the numbers, I'm guessing the problem is in the 60'. This isn't too surprising as the short-stroked 4.8 has notoriously weak low end torque. Furthermore, the stock converter stalls at only 1600 rpm, and at that point the blower is making 4 psi, some help but not much. To top it off, the pcm is pulling about 19 degrees timing on launch. It looks to me like a 3000 rpm stall converter would help things. Does this sound right or am I off base? Any other ideas or suggestions? I know a 6.0L would fix the problem, but I'd like to stick with the current engine if possible. Thanks in advance for any help or insight you can provide.

 

You're having the same problem a lot of us have. The Radix pulling all your timing upon launch and it kills your ET. A stall would help but youre still gonna lag out of thew hole until you get your timing tables worked on so it doesnt pull so much timing.

I just dropped my truck off to have it retuned and a new stall put in so I'll let ya know how it helps me out.

 

wow that make me feel better about my 14.85 n/a. good luck its all in the tune lol.

 

sounds like it is in the tune mostly, are you using the stock radix tune?

I bet that stall will get you into the low 1.9 60' range. I was running 2.0 flat, but your truck is lighter and blown.

 

I think I found the problem. Thanks F8L and Travis for pointing me in the right direction, and thanks to the Search button for fetching me the details.