After I got my 15% pulley, there was the normal flat spot down low. However, 25k miles later I don't notice that spot anymore, but there is a new flat spot from about 5,000 rpm to 6,800 rpm. Could this be caused by a boost leak in the intercooler bellows? The lack of power at this range was never this much. I know it doesn't pull all the way to redline, it never has. This is just less pull than normal. The pulley is not slipping, there is no change in pitch or any belt/metal noise. Would it be prudent to get a set of uprated bellows?

 

start with belt. measure your boost as well. and go from there.

 

I put on a Gatorback belt on,and I'd swear someone tuned the car while I was'nt looking.Sounds freakin amazing too!

 

Belt it is.

 

when mine was stock (02 s) it pulled to redline, and now with a alta intake and 15% pulley it pulls all the way to redline much faster....sounds like you may have a boost leak.

 

i'd bet a decent amount of money on it being the belt. They will slip and will do so ever so slightly without making a peep. Only way you'll really be able to tell since it's such a slow transition to slipping is on a dyno or by replacing it.

 

what size Gatorback belt is needed for a 17% pulley? Anyone know off hand?

 

My belt only has 10,000 miles on it, could it be bad already?

 

what part # belt is it?

 

The part number for a Goodyear Gatorback POLY-V belt for a 17% pulley is GTR-4060537 from Summit Racing.

 

Thank YOU!

 

Intense, I would be interested to know if replacing with the Gatorback 537 helps to at least partially resolve your issues.

 

If not the belt, check your tensioner.

 

Thats why I'm going to change it I'm interested as well. I have a appointment to get my car on a dyno the 26th. I want to get this belt on before that so I can tell if there's a difference. I'll keep you posted Latte. After talking with Jan tho he agrees with your assessment. I've done more than my injectors and ecu can handle mixed with this cold

 

I had oil contamination on the belt, but I cannot fix where I think the leak is coming from. My oil pressure guage sender and the stock dummy light sender are hooked to a brass T fitting. That has drips of oil and a spray pattern around it, but the fittings are tight. To fix this all, Im going to get the Madness oil cooler plate with the sender fittings build into it. Right now I'm going to have to keep it under 5k so the belt doesn't slip untill I get that part.

 

Check belt tensioner, everyones on the right track for the belt its self
how ever the bellows are likely to go bad if they are improperly installed or removed.
If i were you i would seriously look into getting your car tuned by jan.
when i had mine done we found it was lean in the top end quite a bit.
so this could be part of it.
after mine pulls straight to the redline with fury and runs great all over

 

So my belt tensioner's damper is leaking and that soiled the belt in addition to the oil from my leaking aeroquip lines (which are now fixed)

Anyone know where to get just the little damper/shock from the tensioner? I don't want to buy the whole stupid thing if I don't have to.

 

Nothing is currently available. Someone was looking into getting a source for just the damper, but nothing has been announced yet. I had to bite the bullet and put in a new tensioner ($130 from dealer) and belt on for the same reasons.

 

The dealer quoted me $158 for a tensioner today... I'll be getting the GTT tensioner and idler pulley in a while.

 

Don't bother with the GTT tensioner. The only difference is with the pulley.....same damper and short life. Check with Classic MINI or Morristown for a better price on the OEM unit. The life of the damper will be better when the correct sized belt is used for the pulley you have.

 

I do have the smaller than stock size belt. It was the size Alta recomended when I put the 15% pulley on. Is there a better size to use? I've already bought the spare belt. Good thing I have not ordered the tensioner yet.

 

If you are using either the 537 or 535 belt you should be good to go. I use a 535 belt with my 15% pulley.