Before I install the pulley, I wanted to see if anyone has had any major problems directly related to the smaller pulley.

Also, will I have to keep the revs lower with the smaller pulley? I will be running the Unichip ECU upgrade also if that makes any difference.

 

Jason, I believe you are in Da House my friend with the 15% reduction. I went for a ride with this dude up during the Auburn run. Well he was letting me hear what the Borla race sounds like and MAN....we took off and he went all the way to 7000+, shifted to 2nd, but was still at 5500+. It was f-in bada-- dude. I was shocked that he kept the revs. up around where they were. I'm confident that it would be all good. later man.

 

I have the 19%, and increased rev limit to 7200 with the One-Click, no issues so far.

 

nearly 30,000 miles with my 15% and no problems.:smile:

 

If you are planning the 15% reduction pulley with UniChip ECU upgrade then that is fine. Talk to Randy Webb if you have any questions. It's pretty safe and reliable up to redline.
Generally there is no reason to push your revs past 6500 rpm anyway- it's time to shift.

The alternative is to install only the 19% pulley with smaller belt (not needed with the 15% pulley). In this case you don't need the Unichip ECU since it is not that helpful with the more powerful 19% pulley. You do have to be careful about generating heat so just be resonable about driving esp on a long fast track course. For daily driving and autocross the 19% pulley is fine and you don't have to worry about high revs and redline any more than with the 15% pulley. Randy likes the 15% pulley better as it has been tested by JCW and others more extensively.

 

what kinda power you guys getting out of the 19% pulley?

 

Well... 19% with exhaust and intake I am at 198 hp, SAE corrected. Your results may vary.

 

Thanks guys. Ive already got everything except the Unichip sitting on the floor behind me right now just waiting to be installed. James, I am going to leave you a PM about when and where we will meet.

I have given up on Alta with their short shifter. I ordered it mid may and they told me I would have it on June 1st. Now its late June and they still say its not done . All the mods should be on by July 1st though... CANT WAIT!

 

Got a short shift from Helix for my '04 MCS. Easy install, works great. They probably have them in stock.

 

Now that's pushing it. I believe you're revving the supercharger beyond what it was made to do! I have the 19% and try to shift by 6500 RPMs which is the same supercharger speed as stock pulley with an aftermarket ECU.

As far as the 15% goes, the power is linear, so the more you rev it, the more power you get. So you'll want to get the revs up there. With the 15%, you can rev it to redline and not over-rev the supercharger.

As far as the 19% goes, it adds a lot of low-end power (torque) with just a little more at the very top. For one, this really helps balance the power out in the S. It makes most of the powerband feel great. But since it adds so much low and not a lot up top, you don't need to rev it to redline so often.

The 15% is more than tried and proven. Go for it and feel good about it. The only concern would be to have a competent person with experience on MINI pulleys to do the install.