supercharger ratio and rpm?

[tbone280zx]

i'm modifing the m90 supercharger off a 95 regal gs to fit on a inline six cylinder - can anyone tell me what the ratio is from the crank pulley to the SC pulley (which is a 3.5 inch pulley) and approximately what psi at what horsepower is it putting out?
I really need to find this out the size of the crank pulley (i just have the SC and no access to the regal -
is there any other vehicles that have the same pulley that i can steal from?

 

[bmcdearis]

The crank pulley is 7 inch. Therefore, the stock ratio is 1.842 so at 6000 rpm the SC is turning at about 11,000 rpm creating approx 7.5 lbs of boost. I generally saw a 10-11 psi with a 3.4 inch and 12-13 psi with a 3.25 inch SC pulley. A friend of mine with a 3.0 would see 15 lbs..

I think there is about 10 hp per psi but this begins to drop off due to heat the higher you go.

BTW, I spoke to a guy who works at Eaton and does SC testing. He said the M90 should be able to sustain 15.5 k rpm without any trouble.

Hope this helps.

 

[tbone280zx]

thanks Brian -
I'm also looking for options (which cars ) on where to find a stock size (7in.) crank pulley - 6 ribs, 1 inch wide
any ideas?

 

[bmcdearis]

Off the top of my head :Any 97-02 Grand Prix GTP, 97-02 Regal GS.

The other models in the Grand Prix and Regal lineup probably have the same size but I don't know for sure.

Also, there are Park Avenues with the Series II supercharged engine as well. I would assume it is the exact same set up.

Good luck.