pulley bros 103mm sc12 info

[stepan117]

Ok just a note for refrence , i have a 176mm crank pulley from Fensport UK and a new Pulley Brothers 103mm pulley on my sc12.I have noticed after fitting the newer style smaller clutch plate lots of slippage (not the belt) and have now moved to the older style larger clutch plate which has no slippage at all. Both were gapped 1mm clearance but under investigation i have come to the conclusion that the smaller clutch plate has less surface to surface contact for friction clamping on the pulley itself. I am at present running 16psi boost with a Frozen Boost W to A intercooler and the new AVB mod taken from the Air Exhaust pipe from the supercharger to the AVB with most impressive response and tourqe.Thanks to all mod ideas guys

[old_mr2]

got any pics of the pulleys/belts? I am interested to see your setup!

[Q-Authority]

Yes, and let us know just how long the sc12 lasts. As you will now have it spinning a whole lot faster than the manufacturer spec limits.

Good luck with it.

By the way, what two different clutch hubs are you talking about? The PulleyBro sc12 clutched pulley reused the stock sc12 clutch hub, and did not have a secondary smaller one. What smaller one were you using (the jdm sc12 clutch hub)?

[woggin]

doesnt the teflon coating on the rotors start peeling after 14 000rpm???

[X kyle X]

Lol at Teflon melting. And all that. I've seen and heard of this once.

[TERRA Operative]

The SC12 supercharger has a maximum continuous speed of 11,000 RPM (14,000 RPM short term). Any faster and you WILL blow the bearings, it's just a matter of how long they will last before they blow. In any case, it's not that long.

The SC series chargers also have a maximum long boost ratio of 1.8 (that equals about 12PSI) and a maximum momentary boost ratio of 2.0 (14.7PSI) any more than that and the lobes expand due to the excessive heat generated by the over boost conditions and the clearances in the charger close up (there's as much clearance as the thickness of a cigarette paper in there), causing the teflon coating on the lobes to rub on the housing, causing the teflon to heat up even more and eventually melt.

Just food for thought, seeing as you're pushing the SC12 WAY above it's efficiency range.

[feral4mr2]

17psi sc12 FTW!!!

i've only ever had one get rattly in the bearings from over spinning, never had a drama with the rotors.

[TERRA Operative]

The bearings themselves are only rated to 11,000RPM (I checked out the Ogura specs and the bearing manufacturer specs myself), good luck....

[Q-Authority]

You won't necessarily experience a dramatic meltdown, or huge bearing failure, but over revving of these things will definitely take their toll, and performance will be lost. Unfortunately, so many people now-a-days use the largest oversize crank pulleys, and/or smaller sc pulleys, that finding an unabused used sc12 as a replacement is not all that easy anymore.

And people who report large boost pressures are pretty much only reporting the effect of articial boost created by excessive heating of the charge, not an actual efficient cold charge, and/or their boost gauges are quite likely not all that acurate. I've almost never seen a proven system, with a proper intercooler, and accurate boost gauge, report more than about 12 psi, no matter what combination of pulley system they are using.

And so many people think that when they go to sell their highly boosted 4agze's that they can expect big prices for them, but more often than not they find out that anyone who knows much about these cars will avoid them, because they know the wear and tear that this can create, especially without a really carefully built engine.

Here's Ogura's pdf of their performance specs. The TX12 is their current version of the sc12, and has slightly different shaped rototrs, which I really wish we could get, as they look a bit more efficient, but anyway their specs have pretty much remained the same over the years.

http://www.ogura-clutch.com/download...perCharger.pdf

[woggin]

if you want more flow/power go buy an eaton M90 or sumthing or a Harrop stage 2 supercharger(LS1 supercharger)

[TERRA Operative]

You can get the Ogura superchargers, you just have to buy as pallet load of them.

Group buy anyone?