What is the forumula for how fast the supercharger is spinning. I know it was posted a long time ago but I can't find it.

It used 3 variables, the s/c pulley size, the crank pulley size and the engine rpm.

Anyone know the formula as well as the size of the stock pulley?

Thanks in advance,

Jon

 

i think the stock s/c pulley is 3.3"

 

I should have been more specefic, looking for the stock crank pulley. Since the other two variables are likely to change with each persons setup.

 

Good point... sorry i should have figured that

 

I believe these numbers are correct, or at least, I haven't been told they're wrong yet.

Crank is 6.25", stock pulley is 3.34", gm stage 2 pulley is about 3.06", then of course there's sizes all over the place for other brands. Math is

[(6.25 * pi) / (pulleysize * pi)] * engine RPM.

i.e. a 2.5 @ 7400 = (19.625 / 7.85) * 7400 = 18500 s/c rpm.

Hope that helps some!

 

I read over in the .com site that its around 6" so I would venture to guess that you are somewhat right

 

if you have pi/pi they will eat each other if they're apple pie

(6.25/2.5)*7400 = 18500

6.25 is what I've read for the crank pulley, but I will know the exact soon enough

 

Thanks guys, that's what I was looking for....

 

And that is why, if you don't want to overspin your SC, your limited to a 2.75" pulley at 7k rpms. If your willing to settle for a lower redline, you can go with a smaller pulley.

 

WopOnTour said the blower max continuous redline was 16000 rpm, and short burst was 18000. I thought it was lower but he said 16000 is the sustained redline.

 

hmm....I have a 2.6 and don't have any issues. I think what you're forgetting here is that the 16000rpm limit is for continous not the occasional.

 

Well I suppose you could run it up to 18k, but then you have the massive heat problem that comes from having a roots SC and running it close to its limit. Very inefficent, hot, and actually produces less power (more low end torque though).

 

Mase is that your dyno on the TAG racecraft site? 240wtrq at 2000 rpms must feel insane bro!

 

not when ur clutch is slippin like MAD!!!

TAG's getting me a Bully Clutch, same one as the 500HP Solstice.