Bryan@SpeedInc

Our ZR1 making a 787RWHP dyno run. We were shooting for 800 to the wheels, but belt slippage was causing a boost drop from 18 down to 16. We are going to reconfigure some idlers and add a Gates HD Green belt, and once slippage is eliminated or reduced, we should easily hit 800.


Mods list on our blog below. We have since changed to the 2.35" pulley which is why we are battling belt slip. We have also added the Flex Fuel conversion kit, and are running E85.

http://www.speedinc.com/blog/2010ZR121/

Nanook

Nasty..

whatcop?

Gkzr1 posted up a thread with what you need to run the Gates belt.

Bryan@SpeedInc

Thanks, that's what we are going off of. Gotta love the forum help!!!

Ballbearingturbo

Why not use the 14% lower pulley?

Bryan@SpeedInc

That's what we are using.

Ballbearingturbo

I have the 2.6 and 14% lower. I was going to switch to the 2.3 and exchange the idler with a 100mm idler and use the same belt. This is what ace32x has done and apparently has no belt slip.

I'm assuming you were using the 2.3 with the 14% and same belt from the 2.6 setup using the stock idler?

Bryan@SpeedInc

Using 14% lower, switched from 2.6 upper, and went to the 2.35 with the stock belt, and stock idler.

Bryan@SpeedInc

Does GKZr1 not have an overdriven crank pulley?

Ballbearingturbo

No he does not.

narush

I had the 14% lower with 2.35 upper saw 20lbs of boost but decided to go back to the 2.6 due to fuel octane issues.

I was not ready to run straight race fuel in car nor am I close to an E85 station.

Bryan@SpeedInc

Wow, he's seeing a lot of boost for a standard pulley!

Ballbearingturbo

Every thing that increases efficiency will lower the boost (ported heads, blower, snout, header, cam, etc). At the time of this thread I'm pretty sure he had stock blower, snout, cam which could explain the higher boost. As of right now he's seeing 16.

I'll be installing my 2.35 and 100mm idler using the same belt I have now this month.

Bryan@SpeedInc

Awesome, we'll keep an eye out for your results!