hi, i just installed a 15% pulley and i tested drive it, but it doesn't feel any difference as other people said. Anyone know why? it is a 02 cooper S. please let me know thanks

 

nothing? did you put the original belt back on ,, it could be slippin some. mine did.

 

yea i put the original belt back on, they said my original belt is ok

 

Yea, something must be wrong...because there was a MAJOR difference in mine...and I love it!

I would replace the belt with a new one, like a Gatorback.

-Cody

 

mine looked good but the power delivery was weird . so that plus some pulley noise led me to change it and wham!!! power back . changing it was about an hour . pull the wheel then the inner fender then the pry bar with the 16 mm socket to loosen the belt . plus you gotta stick a small drift in the hole in the tensioner slider. to hold it . do a search under napa belts you'll get the part # that way .

 

whack it at about 4000 rpms if you get a weird smell ....you're slippin'. also if you've got an 02 you might be ready for a clutch .

 

While I did notice a major change after I got my 15%...it was not as dramatic as I expected. However, it did seem the the ECU adjusted to the pulley after a few days and the difference was huge. Maybe it was just my perception, but I do know that our ECU's are highly adaptive and will need a little bit of time to adjust to every mod that you do.

 

Is yours a JCW?
The JCW pulley is about 14.5 I think, so maybe it wasn't that much of a change.

Paul

 

if you can't feel a difference, try checking your bypass valve. It might be bad now? If not the bypass valve change the belt.

 

I agree I did the inake first and then the pulley a week later. I noticed the intake a lot but not so much with the 17% pulley. But after I put the Fireballed software the car was night and day. I smoked a JCW car hard.
Mario

 

thanks for all the reply, do i need to get a jcw belt? or the original belt is fine?

 

Use a stock belt. You will be fine.....

 

No just the right size belt. I think its like 53.????" but u can do a search. maybe use the 17% belt for a tighter fit. Your car is a normal MCS or a JCW package?

 

My 65 year old father test drove my car after the pulley install and he couldn't tell any difference...but then again hes not used to driving it everyday.

 

What car do you have? Is it a JCW or a regular MCS? Eitherway, with a 15% pulley the JCW belt would work fine as would the stock MCS belt. However, Gatorback belts are highly recommended if you're looking for a replacement. Do a search and you'll find the part # for a 15% pulley.

 

Sorry to be off topic but how do you like the OBX header? What cat did you use and is there a felx joint? Could you feel it on the butt dyno?

 

Do you hear a louder supercharger whine?

 

you won't feel any difference unless you stomp on it, (WOT) loading the car hard with the rpm 3500 and up to redline.

 

If this is an '02, how many miles are on it? Even though a JCW belt shouldn't be necessary, if you have higher miles, you may consider replacing the belt anyhow - and if you're replacing it, you might as well get the JCW (or similar size) belt. It is something that should be replaced at service inspection II, but there are already some folks well beyond that mileage.

How long have you owned/regularly driven the car? As mentioned already, while the change is noteworthy, it doesn't turn your MINI into a dragster. If you haven't driven it regularly (everyday) for at least a few weeks, you might not be able to discern the difference. That is one reason I waited a month or so to install mine.

 

Was there already a reduction pulley on it?

 

a boost gauge should tell you if your pulley is working correctly

 

Hey CupOfTea,

There's a few things that might be getting in the way of the 15% making power. You could have some engine electronic issues, where the ECU is retarding timing too much and stealing the power. You could have some gas issues where you're getting detonation/pinging, so the ECU pulls timing, what is your timing on WOT acceleration?...your mechanic should have ODBII scanner that can read realtime info, if not, find another mechanic! You could have a boost leak. What's your boost readings?...your mechanic should have a boost guage, if not, find another mechanic! You could have some mechanical problem that robbing the hp from being put to the ground. Did you dyno it, before/after? How about your airfilter?

 

I put the Alta 15% pulley on my 04 MCS. The only other mod was a milltech exhaust. While it was being worked on I also had the mechanic replace the belt with a Napa 060539. As others have said up til 3500 rpm seems normal...after that it definately gives me a really nice kick.

By the way...the old belt looked perfect but for $20 I replaced it anyway (only 19,000 mi on it) Now keep it in the boot as a spare

Attached is a belt matrix that another poster pit up a while back

 

I wasn't too impressed with just the pulley mod, until I introduced more air to the SC via the Dinan air box. Then it just woke up.

 

Like JLM says. With a lot of driving under 3.5k revs you are NOT going to notice THAT much of a difference, because at lower revs boost (which the pulley mod addresses) is not an issue. But if you are not noticing a difference from 4k to red-line, then there may be some other problem (belt or something).