Pulley

[mongol]

I currently have a pulley on the head unit that measure's 4.5 inch's. I suppose its the stock one. When I bought the supercharger it came with a smaller one that measures about 3.3 inch's. The pulley on the crankshaft is 6 and a quarter inch. Can I use the smaller pulley with my setup. I don't want to overspin. It is as follows.

gt40 Heads
Gt40 Tubular upper and lower intakes
Tfs1 cam
255 lph fuel pump
24lb injectors
70mm throttle body
73mm maf
fmu with 8:1 disk
k+n


Thanks Kris

I know you guy's have better things to do then answer my ?

[speedytang]

Way to small you will have the unit over spinning by 4200 rpm on your tach. Belt slip probably occur anyways since not enough belt contact.

[mongol]

Hey speedy. I know that some people change the pulley's around to get more boost. I don't mind reserching to find out what pulley's to use but would my fuel setup (above)be a limiting factor if I was to up the boost. If so I'm not even going to worry with trying to find out what pulley's I can use and I will just sell the 3.3 pulley. Thanks Kris

[F=MA]

You might up the boost with a smaller pulley but, in addition to overspinning the ball drive and belt slippage issues, what your really doing is just plain heating air.

The SN standard impeller is pretty efficient in its intended range (around 5-7 psi) but, performance drops off drastically when it's pushed hard and charge temps rise alarmingly. This is an old school blower and it really doesn't have much headroom.

Your fuel system can support about 400 horse so, That's not the issue particularly. That's using the FMU disc you have and the theoretical max boost of 8 PSI from the SN.

F=MA