Thread: 2.6" or 2.7" pulley?

Last summer I was running a 2.9" pulley on E85 and 24° timing with no knock. This summer I'd like to drop the pulley size and run less timing. I figure I need to go smaller than a 2.8"

I read that anything smaller than 2.8" requires machining the snout. I've already ground the fins off. Is that enough to run a 2.7" or even 2.6"? At what point is belt slipping a problem?

Thanks!

This is what I needed to do


im using a 2.8 but with 8rib belt. No slip. But I'm anticipating it with my 2.6 so I have the prj belt wrap just in case.
If you need to borrow the tool PM me here or on RGS if it ever comes back up !

You need to machine snout for a 2.7, and without a belt wrap your getting belt slip even on a 2.9, it's the nature of it..

Depends on what size belt tho. You can't say sure until you know his set up / and if he currently has a 2.9 and no slip - well there ya go!

Get a belt wrap for assurance. They look cool too.

I've been running the 2.9" pulley for a couple of years with no slip. I'd rather not use the belt wrap kit.

Will the 2.7" fit if I just grind down the ribs on the snout?

2.8 and timing. i know 2.8 fits stock snout.

edit didnt see your already at 24* DAMN

Let me try this from another angle. Anybody have a 2.7" or 2.6" ZZP or Intense pulley that they could measure the ID of the backside for me?

I have a 2.6 on the shelf at home

Belt wrap isn't needed and is laughable.

I didn't see, is this a GenIII or GenV car?

Either way, I'd run a 2.6" and back the timing a smidge. I remember reading somewhere anything north of 22-23 isn't worth the aggressive stand; I mean, unless you just kept running it up until it started knocking. What's the WOT AFR reading at? I'd mess with that more than anything.

I'd almost think once the blower is spinning that fast it won't make anymore power, seen it before where trying to add boost doesnt increase power because now the air is even hotter and blower is far past it's efficiency range.

Quick. Someone que in slo with his maps and charts

That is not correct.

2.25" inner diameter

Thanks! I just measured the snout and it's just a touch over 2.25". Maybe 1/32" over. I bet (hope) the 2.7 would work with just the fins removed. For me, the 2.6 was probably pushing it anyway.

Smoothflow pullies can be run down to a 2.7 without machining the snout. I don't know about any smaller though. I do know that there is not much room left between the snout and the pulley though.

Man, you've only got an open cone with a 2.7"?

Major noob. Hope it pops.

That's just how I roll dude. When in doubt, more boost.