ChiTownSS

Who's currently running both underdrive crank and alternator pullies on their M6 cars? Reason being is that I know a lot of people are only using the crank pulley and not the underdrive alternator piece.

Being an M6, I shouldn't have a problem right? My idle will be bumped up to 900 rpms to prevent surging.

Any info that you can provide is appreciated.

ChiTown

BADSS

iTrader: (7)

I am running both ASP pulleys (crank and alternator) on my car. 99 SS M6. No charging problems to report- still running the original battery, in fact. My idle is set at 900 RPMs due to my cam, but I had no problems with a 750 RPM idle, either.

Jim98TA

I run both of them with a stock idle. Everything is pretty normal. Sitting at a red light the voltage drops a bit, and if you add turn signal, wipers, etc it will drop more. As soon as you get going, voltage goes back up though. Been like that for a year and a half now with no problems.

BAD XXX

No issues, get them, they work!

SSCamaro99_3

iTrader: (1)

I do not run the alternator pulley. It was walking my belt off of the idler pulley between it an the power sterring. It was one rib to tall.

kp

iTrader: (34)

I'm running one of those small SVR batteries and both pulleys, stock idle speed. With the blower on high, lights and wipers on the voltage drops pretty low but i've been driving it for three months like that and its always started..

2MCHPWR

iTrader: (10)

i have both and it's fine. slightly raised idle. original battery too.

ChiTownSS

SSCamaro99...what was one rib too tall? The underdrive alternator pully? I hope that doesn't happen when I put them on...Oh well, guess I'll find out.

Thanks guys!

SSCamaro99_3

iTrader: (1)

The alternator pulley was to tall by one rib. It put angle in the belt where it goes to the idler above it, and walked it off after less than 50 miles. The stocker went back on and all is well.

verbs

Running both pullies here with an extra 300 watts powering my 10" woofer, and I'm running a 20lb racing battery. All in the 110 degree heat

No problems.....yet

ChiTownSS

Thanks SS & Verbs

slow

iTrader: (7)

Question... is the alt pulley really larger, (therefore an underdrivedrive pulley?)

most pulley sets for other cars, use a smaller alt pulley, to increase speed of the alt.

I am planning on installing the vortech i have soon, so i have not looked into underdrive pulleys, but was wondering.

Thx

Ryan.

TaTommyWS6

I believe there are two alternator pullies. A smaller one for more power, and a bigger one for more charge.

Tommy

slow

iTrader: (7)

smaller would be more charge, as the alt is not driving the belt.

Ryan.

TaTommyWS6

My bad! But you get the point! They make two...

slow

iTrader: (7)

cool, thanks

Ryan.