So I replaced my crank pulley with the 2% ALTA pulley along with my belt tensioner (OEM, nothing special). But when I put the belt on I noticed it was quite tight, almost too tight. But the ALTA instructions called for the use of a stock belt size. That's where I got confused, it was a larger pulley than before, yet they say to use the stock belt size? Doesn't seem to add up and I don't like the idea of having a small belt ruining bearings or worse...

I've also noticed that the SC seems to build up a bit before it actually releases the boost. It's quite a noticeable change from before, and I highly doubt that's from the 2% pulley.

Any input is greatly appreciated.
Thanks guys!

 

Was their recommendation dependent on installing a smaller, say 15%, S/C pulley at the same time? Are you sure you already had the stock belt size on in the first place?

 

No, they had a chart containing different SC pulley combos and crank pulleys. They say with the stock SC pulley and the 2% crank to use the stock belt.

Yes, I measured the belts and they seemed close. Off, a bit, do to wear and a bit of stretching I assume.

 

You'll be fine with a stock size belt and a 2% pulley. I'd be more worried about the pulley either fracturing the spokes or spinning on the crankshaft.

 

I agree. I don't like the non dampened pulley at all. Just hoping it won't mess up anything before I can get the dampened pulley on there.

 

Is there any evidence of non-dampened pulleys breaking or spinning on the crankshaft?

 

Sorry to revive an "out to pasture" thread, but I was pleasantly surprised when I saw the date. Assuming I put the ATI -2% crank pulley on that same year - the latter part of 2016. Then I've gotta say. ATI fluid-filled crank pulleys are a top-notch investment! Almost 6 years later and my belt tensioner (eBay special) needed a replacement, other than that everything else has been top-notch.

Just wanted to take the time to make that PSA.
Thanks, and have a great day!

 

This is the best kind of dead thread reviving! So many get abandoned without closing the loop.

My anecdotal evidence is installing an Alta pulley at 107k miles, driving it hard for 25k miles and having no issues whatsoever over 4 years.

I just installed another one on my 06 JCW at 146k miles after the OEM failed.

On my 300ZX I've run a lightweight crank pulley in place of the OEM harmonic balancer for ~40k miles, half of that at high horsepower. No issues.

I also installed one on my '97 GTI VR6 many years ago. Ran it for roughly 60k miles, probably 15k or so on the track. Sadly the motor died to an oil cooler failure otherwise the experiment would have continued.

Totally anecdotal; but I've never had a negative experience nor oil changes with fun glitter. The one thing I haven't done is a UOA to check bearing health before and after.