ralph11sec

Charger belt always snaps off/shredded at high rpm even on the dyno.
Can't find any misalignment on the pulley we even changed to a new pulley
but still the same problem. Does this issue always occur on JRSC setups?

TheShodan

iTrader: (14)

yep. Sadly this was a normal thing on the older Jackson SC Eaton setups. Everyone upgraded to a higher level belt, but unfortunately I can't guide you to the part number you could find in an autoparts store, since these systems are discontinued.

ralph11sec

Yeah I think what we got here is the older JRSC. Too bad about the issue on the belt. It was giving decent power at 280whp.
So we just need to find a higher level belt is that it?

Veris

Your alternator is most likely slightly mis-shimmed.
http://www.ftlracing.com/shim.htm

Alternatively you could have a loose alternator bolt.

Lastly I recommend GATES/NAPA belts. If you can't find them go to a goodyear gatorback. Cheap belt will break.

A good belt with good alignment should last a year even on high hp setups. Mine regularly see 9000+ rpm (18000 at the blower) and about 100+ 1/4 mile runs annually. On the other hand if one of the above isn't correct I'll loose belts VERY frequently.

Veris

No.

ralph11sec

thanks will try that. btw how would we know that the shim is already enough or the alternator is perfectly aligned?

Spawne32

iTrader: (3)

Look at the belt on the alternator pulley, you should be able to see if it looks like its twisting one way or another, that should give you an idea of how you need to shim it. All it takes is a small amount to send it crashing into the side of the engine from it rolling over a few ribs.

TheShodan

iTrader: (14)

At least when I ran them in 1999 it was still a problem. So if its changed great. If not....well..

Spawne32

iTrader: (3)

Well they shred typically from over tightening or horrible alignment issues which is more common then I thought. The 4 rib setup is ehhh but ive never had issues with slippage though. We will see once i get the stepper pulley on.

Veris

If you are running quality belts and the bolts are all tight then you have a misalignment. One washer can make a huge difference.

To line up.

1) eye ball or use a laser
2) check for tension differences on each side of the belt
3) look for where on the belt and pulley. Typically belt will show wear on the edge where pressure is. Additionally the pulley will show more wear on the problem side.

MRGRIM

iTrader: (1)

another way to check for misalignment
this method is easy to use when in a tight space
Use the tip of your finger on the edge of the belt in the middle between pulleys
push down on the edge and then on the other ...if the belt twists more on one side than the other then there is a misalignment

or you can go the more exspensive route and replace your pulleys with up graded ones from ASP that have the Flange / Lip to stop the belts from comming off

Veris

This is the tension method I mentioned, but explained much better/clearer.

ralph11sec

ASP sells upgraded pulley? can you share the link? tnx.

Veris

www.aspracing.com/index.html

You'll need to call as they are not posted on the website.

Additionally this won't solve the issue if alignment is not close to correct. That said a great idea. Grimm and I both run their pulleys.