New mods

[Sully]

I have a 2.2 on 2.7 pulley making roughly 300. You want to run that 2.8 pulley you need to do a 6 rib conversion to eliminate belt slip. The strength of belt mean nothing when talking about slip. And you can only get it so tight before you need to add surface area to get more grip. I had moved the alt towards the front of the car, tightened the crap out of it and slew of other things to get rid of belt slip. It doesnt work. You need to swap out your crank, alt, and AC pulley to the SS/SC 6 rib configuration and run a full belt. Look at it this way. You run fatter tires for better traction right? Same deal. By going from 5 rib to 6rib you add 20% more surface of the belt to grab that little pulley.

Tensile strangth is only a factor in belts when you want to discuss them holding the set tension and not stretching out as bad over time. Will a 5 rib last as long at the same amount of tension.... not according to physics. Will it still last a long time, yeah sure plenty of people have done it and it works fine. Im just saying you need to get the 6 rib for more "traction" and it will give a bit more longevity too.

 

[Tom]

good info^ makes sense,thanks!

 

[cobalt123]

ill keep that in mind

 

[Sully]

oh and I know many people are doing it no problem, but Id reccomend swapping the alt to the ss/sc alt. they spin opposite directions. Its not huge, but they are designed to spin certain ways. Cooling fins for example make a big difference.

MRZ sells lightweight 6rib pulleys for the alt and crank, im not sure about the AC. I got mine for pretty cheap. I did have an issue with the alt pulley when my alt seized up, but the odds are that any pulley stock or not would have had the same issue.


I would also reccomend that people running those eatons do what GM failed to do and comply with the eaton engineering. Eaton put a threaded bolt hole in the end of the shaft for a reason. Why GM decided not to put a bolt in there I will never know. Go buy a M7 x 1.25-1.5" bolt and a 1" washer and tighten it down in the shaft. I keeps the pulley from doing anything stupid. Ford, Jag, etc all did it. I have no clue why GM thought they were smarter than Eaton, but you can fix it for very cheap!

 

[Jn2]

The bolt hole is m8x1.25. And I'm not getting any belt slip on my set up. Sure I could swap to 6, but I c no reason for it when it holds it fine the way it is now. No need to mindlessly spend money. 5 ribs hold my 2.8 fine.

And as a update to everyone vince got my car running nicely now. Getting 16psi and loving it. Although my clutch hates it

 

[sloancallaway]

The bolt hole is m8x1.25. And I'm not getting any belt slip on my set up. Sure I could swap to 6, but I c no reason for it when it holds it fine the way it is now. No need to mindlessly spend money. 5 ribs hold my 2.8 fine.

And as a update to everyone vince got my car running nicely now. Getting 16psi and loving it. Although my clutch hates it

so when are you getting a clutch and what kind are you going with

 

[Jn2]

so when are you getting a clutch and what kind are you going with

Getting excedy stgII, hoping to have it installed early January. Along with zzp's boost reference system increase fuel psi. After that ima chill on performance modsand work on other stuff

 

[sloancallaway]

Getting excedy stgII, hoping to have it installed early January. Along with zzp's boost reference system increase fuel psi. After that ima chill on performance modsand work on other stuff

wicked... well its lookin good man

 

[Jn2]

Thanks. It's a fun car to dd, but clutch slippage ruins it can't wait to get a new one

 

[06blackbalt]

nice 16psi can wait for my retune