would changing the 2.75pulley to the 3.1pulley would i be getting more timing on the 3.1

 

You'd lose a pound or 2 of boost. Your intake charge would be a little cooler since you wouldnt be spinning the Radix so fast. The cooler air may allow for a LITTLE more timing but, I dont know that it would make up for the lost boost. Hit the dyno and see if it helps.

 

Yes you would be able to run more timing. I had a 3.1 with 18 degrees of timing. HOWEVER, soon as your intake temps rise, the pcm is going to pull timing. With that 2.75 pulley, it is probably pulling timing before you even got WOT.

 

thats true. so if with the 2.75pulley im running about 8*'s of timing and with the 3.1 should i see it in the upper teens or what

 

Who's tuning are you using?Are you actually setting your timing to 8 degrees or is that the result of KR?What pulley were you using when the tuning was done?

 

i have the nelson tune im tuned for the 2.75

 

whats kr

 

KR=Knock Retrad. The knock sensors pull timing if the engine is detonating (knock). I have a 2.75" pulley and run 17.5* of timing and get none pulled due to knock or anything else. How do you know you have 8*? Are you scanning/logging?


Mine is on a 6L, I assume you have a 5.3L?

 

yes i have the 5.3 thats what it read when we street tuned it. i never had any problems with the 2.75pulley in washington state but as soon i came down here this chet is acting up why dont know went from a 12.79@105mph with stock stall and 26's slicks with 55* weather to 13.05@102mph in washington state at 65* weather, here i ran a 13.67@95mph at 69* weather with the tb stall and 28's slicks, but i dont think the tb stall or 28's slicks have to do with the motor of pulling much timing. i mean i dont know much like you all do but i do know that something is up slowing me down chet loads. so i got the meth kit.

 

It is probably the pcm pulling time from high iat's. You can easily run 16-18 degrees of timing with the 3.1. The high iat's from the 2.75 pulley is probably making the pcm pull a ton of timing, especially after a 1/4 mile run. There is a huge difference between 8 and 18 degrees of timing.