View Full Version : What is the s.c./crank drive ratio of a 95 bird?

08-02-2008, 03:46 AM
I'm driving my s.c. 2.32 x crank speed but I have it on a S10
Thanks for your help

08-02-2008, 10:11 AM
An 89-93 SC has a 2.66 drive ratio and a 94-95 SC has a 2.57 drive ratio.

08-02-2008, 02:11 PM
Wow! I though I was overdriving my m90 as compared to the m90s on the thunderbirds. Maybe thats why I'm only getting 11 psi.....hmmmmm. What size is the crank pulley on a thunderbird? (and how does the jackshaft factor in)?? My crank is 6.5 and s.c. pulley is 2.75"


Here's some pics of my setup...

08-02-2008, 02:29 PM
opps here they are...

08-02-2008, 02:36 PM
Nice work, diy fabrications like that are nice to see.
One thing... sc belt does not wrap the sc pulley very much... I could imagine that driving sc more than that could make belt slip quite easily.

08-02-2008, 02:49 PM
The crank pulley diameter on all SC's is 6.842 inches. We also use a jackshaft pulley that can alter drive ratio, as well.

08-05-2008, 01:14 AM
Thanks guys...Hey I read GTPs spin their superchargers at a ratio of 1.842 (8 psi) yet they make 10 more horse then the super coup, what going on there?

08-05-2008, 09:53 AM
they are of the inverted variety aaaaaa much better flowing design with central inlet they also use blower to assist a well tuned engine verses our engines that are detune to run a blower we run lower compression and milder cam .

but look at their torque we surpass their torque we need torque for our heavier cars.