I am currently running a 3.4 pulley and Badly in need of an upgrade! What do you think the Horsepower, Torque, 1/4 mile difference will be between a 3.2 pulley or a 3.0 pullley with headers, both will be running around 8psi since I have heard you loose 2psi with headers. Is it worth it to buy the longtubes for the cost ($525 OBX) or will I see the small differnce? I know tunning is going to be needed and dont want to do the pulley have it tuned then add the headers and have to have it retuned.

 

Im in the same situation,im running a 3.90 pulley at 5-6 psi,im going o install a 3.70 for 8lbs as well-they say for every .10 you go down its like 15hp.good luck man

 

What engine size? Which blower? 112,112HH,122?

 

Mods in Signature.

 

Dam.....I swear I looked. The 3" pulley with long tubes won't over boost you. Will need a tune though. A boost cooler would be a nice addition. You'll be around 9psi. No need to do one then the other. I don't know the HP increase, but I do know you'll like it!!

 

You should get quite a gain by adding long tubes and pulleying down.

 

My truck mods are similar to your own. I have LT's with my Radix and am currently running a 3.3" pulley and seeing 7.5~8 psi at wot.. LT's will help with efficiency and a good tune will be a must to realize the full gains.
Oh yeah...it will be a lot louder too! Adding high flow cats will help with the noise a lot too.
DO IT!

 

5.3 with a 3.0" pulley and long tubes would be sweet! You'll probably be around 10-11 psi though, not 8.

 

Yes. True. I make between 172-182kPa with the 3" pulley, depending on weather, a solid 175kPa average. (175Kpa=10.7lbs at sea level)

 

How much less performance will i get by just going to a 3.2 pulley and not putting on the headers?