UD Pullies

[Pete]

I don't have prooven facts before or after,but to me they are worth there weight in gold,basicly they weign half of the OE steel pieces and if they make more power that is also a plus.

Randy can i twist your arm to make an alimunum PS pullie
I will need a custom made pullie for my next trick on the LT5.

Pete

[FU]

I "think" he makes an aluminum P/S pulley already.

[8upZR1]

I agree, the underdriven pulleys are worth every penny. I fell in love with them during the first test drive. I haven't noticed any of the problems normally associated with slowing things down. Too bad there isn't enough room to hang a large cogged pulley off the snout of the crank.

[1990 quasar blue]

[QUOTE=8upZR1] I fell in love with them during the first test drive.QUOTE]

Can you elaborate?
Thanks

[8upZR1]

Yes, I will elaborate. The HP increase from the pulleys was noticeable enough for me to feel it when I first put them on, which ussually does not happen with a mere pulley swap. I am not saying that I gained 50 HP or anything but the difference was noticeable, particularly when powershifting, as the car had a more violent side to side wiggle. I dunno #'s but it was a pleasant increase especially when considering that there are hardly any bolt ons available for ZR1's, and even fewer are cheap. Also I have not experienced any problems what so ever regarding engine temp or electrical charge. The pulleys I got were also beautifully machined and fit sans hassle. You can not ask for more from a mere peice of aluminum.

[XfireZ51]

I spoke with Marc Haibeck about this last week. He advised against it and didn't think much was gained by it. Has anyone ever quantified the effect?

[1990 quasar blue]

Originally Posted by 8upZR1

Yes, I will elaborate. The HP increase from the pulleys was noticeable enough for me to feel it when I first put them on, which ussually does not happen with a mere pulley swap. I am not saying that I gained 50 HP or anything but the difference was noticeable, particularly when powershifting, as the car had a more violent side to side wiggle. I dunno #'s but it was a pleasant increase especially when considering that there are hardly any bolt ons available for ZR1's, and even fewer are cheap. Also I have not experienced any problems what so ever regarding engine temp or electrical charge. The pulleys I got were also beautifully machined and fit sans hassle. You can not ask for more from a mere peice of aluminum.

Thanks much.