i have a flowmaster muffler about to get a catless y pipe, intake new spark plugs and a dyno tune and i have dr on my ls1 right now. how much time will this take off my 1/4 ? thanks

 

Don't waist your money onb the dyno tune yet. Get O2 sims so you don't set off a engine code. By intake I assume you mean a lid, that and the DR's are the only things that will help you in the 1/4. you should be able to hit a high 12.

 

With all those mods, I'd just get a hypertech tuner and use the 100 octane track fuel. That should shave days off your 1/4 mile time

 

Ahhh...no...100 octane will do nothing (octane in and of itself does not make power) for the car and the Hypertechs I have seen have actually lost hp, and yes this was on a dyno in front of my own two eyes. The ECU on these cars is pretty good at reacting to mods. I never did a tune untill I swapped the cam.