I have a ls2 gto F1 blower running on the factory 6 rib belt line, current pulleys are stock crank pulley, 4.25 blower pulley, with a 10psi waste gate to keep boost down on the stock engine,
I was reading on some other forums about ford lightnings running a over sized crank pulley to increase boost instead of going smaller on the blower, If i go with a 8.5 crank pulley i will max my blower out a 6500rpm with the 4.25 blower pulley so I can try to keep belt slip down, but im worried about over spinning the P/S pump, and all the other accessories,
do you guys think there will be any issues with this
anybody tell me what boost level i will be at roughly?
fully built stock cube, healthy cam, stock heads

 

What about an 8" crank pulley instead?

 

I could see using a larger crank pulley if you were out of boost, but you're already using a waste gate to keep boost down to keep the stock engine alive. Why do you want to push the blower even harder which will require reliving even more boost. Working the blower harder can increase the inlet air temps and may also cause more belt slippage. You main problem is trying to use the F-1R with the stock 6 rib belt set-up, which I just don't see it working. Bob

 

^ This

 

I could see using a larger crank pulley if you were out of boost, but you're already using a waste gate to keep boost down to keep the stock engine alive. Why do you want to push the blower even harder which will require reliving even more boost


^
This as well...hell it was all correct bob lol. To the OP...thats just silly to pully her down for more rpm when you dont use the boost anyway...get a forged motor and a 8rib setup then go game on

 

fully built stock cube, healthy cam, stock heads[/QUOTE] (first post)
this engine is being built, waste gate will be taken off once the engine is forged, I know its asking a alot from a 6rib,

 

I doubt the 6rib will do much more then it is now. Start piecing out the parts to upgrade.

 

x2 my F1A slips the freaking 8 rib!

 

The 6 rib with F1 supercharger will be problematic. I think the 8 rib will still have issues. A 12 rib should turn the F1, even better if it's 8 inch.

Kurt