Please don't bash me to bad .I don't know either .
here's the deal a 99L ,I just had the recall done and put in IT20 plugs ,a 6#and a 90mm with metco air filter ,I also have a Magna flow cat back it was on the truck when i got it ,and it has 4:10 gears and 20" on it too [IMG][/IMG]

 

[IMG][/IMG]
There

 

get a dyno tune, you are too rich. There is a lot more power to be had there. Your numbers will come up.

Vinny

 

It was tuned with a autologic chip ,its a safe tune but it seems low to me,whats usual timing that you guys run

 

a common tune for an autologic chip would be say 16 degrees advance at WOT..

 

Mine is set at 20 degrees ! I was thinking it would be in the high 380's or so ,it there a different way the dyno reads mine is SAE

 

Hmm, that is off
But as said, your AF is so rich that it's actually
goes off the chart at a very important RPM area
(where you are peaking with your
HP + Torque)
There is plenty more power left in it,
if you decide to get a more aggresive tune.

 

get a dyno tune. i made 385 and 480 with a 4lber, filter, and a reflash. you should be in the 400s easy and trq should be up in the 490s if not better good luck

 

do the 4:10 gears and 20" hurt the dyno reading ,I know the 20" well slow me down some at the track