92redhatch

It seems like everytime I go to my local 1/8 mile track on slicks I have to bring 2 or 3 spare alternator belts. Has anyone else here had the same issue? Is there a way to fix this issue?
Setup is a 84x89 with a pte6765 on 22in mt slicks

boostedcivicsir

look at the pulley alignment. plenty of people are 10k plus and not having issues. i dont know what specifically they are using as far as a crank pulley, i use street fluidampr, so i cant say.

92redhatch

I'm using a stock crank pulley. It's fine when the car is on street tires. Even on the dyno it's fine.

HiProfile

Do you run the same boost with street tires? I'm guessing not, and there might be juuust enough twisting of the block with slicks to kick off the belt. AFAIK some alternators and brackets are slightly different between motors. If your pulleys are the slightest bit misaligned (either sideways or not parallel), there's a chance an extra force will nudge it off.

The only close scenerio I know if is with JRSC belts. Sometimes a misaligned kit will kick the belt over a tooth, or flip it over.


Regardless, maybe you just have a very smart motor. Assuming everything works at 11.5v, it will free up a few HP...

BrowNKiD

How long has the car been running? A friend of mine had the same problem, we found out too late the the engine builder didn't leave the correct clearance's for the rods. Eventually the number 4 rod bearing spun and junked the motor.

turbo-crx

I had the same exact problem last yr everytime I tried to go to the track. The first pass the belt would come off. it never happened on the street, only at the track....found out the housing the driverside motor mount sits in was not welded to the car anymore and the motor was moving causing the belt to come off. So i welded up the housing, and it is golden now.

fukenricen

i had the same issue last year, my crank gave way after some time. i noticed when i would miss shift the alt belt would jump or start to shred. i still haven't found the issue. maybe it was my crank but i had the same issue with my last motor.

tried a new alternator
even switched over to a 6rib pully on the alt and crank pully.
very very frustrated too

90teg

I was having the same issue. What I did was loosen the alternator belt a little and it stopped doing it. I had solid mounts and an Exedy Twin

92redhatch

The car has been running a few years I never drive it so it probably has 2k on the motor setup. Now that you mention the mount i'm going to check to make sure everything is on good. I have the ac mount and the tranny torque mount still on also. I don't have traction bars.

PeakBoost

you wouldnt happen to have a twin disk or hrb without a pedal stop would you?

253_TSP

Could be the alignment Make sure the bolts on both you alternator brackets are the correct bolts they should be marked (A) on the heads, they have a shoulder to help align the brackets.

92redhatch

I don't have a twin disk (I'm going to need one soon). Ill check the bolts

.CUBISH.

i was having that prblem with my nitrous car.. it would only happen in rapid accel...like from a dead stop or something.. make sure both pulleys are clean in the groove..when the old ones break they leave a lot of crap on the pulley. and done use advance auto parts belts

BlownHatch

i am having the same issue,jim stewart motor,ati pulley,exedy twin,tried everything,cant figure it out if i dont figure it out soon im bound to hurt something.somebody hurry up n come up with a idea i havnt tried

swapit

It might just be the stock crank pulley your using.There are some that a have a higher lip on each end which helps hold the belt on.I think its a gsr one i not real sure anymore but we used to have some all motor cars that would spin the belts on the street and at the track if the car was reved over 9000rpm and i noticed that difference and switched the crank pulleys and problem solved.Look at your crank pulley and see if the belt seats almost level with the edge if so thats not the one you want to use.The belt will seat down real far into the pulley and the lip will be real high.

92redhatch

I'll take a pic of my pulley.

Boostin Ex

I had the same problem with my stock crank pulley any time i reved the car past 9,800 it would take the belt and turn it inside out but it would still be on the pulley then it would throw it soon after that year I went through like 6 belts. This past year with my ATI Race Dampner i did not have not even one issue and the belt still looks fine. Most of the aftermarket dampners also underdrive the altenator so it helpsa lot with belt issues with the high rpms.

turbo boost

iTrader: (1)

i have this same problem...sometimes it will filp the belt or throw it right off...but only at the track with slicks..wont do it on the street...i have a ls crank pully..maybe ill pick up a gsr pully see if that helps

SlicksMH

Belt to wide and it rides to high above the pulley. It don't take much.

SlicksMH

fknfast

stock block or dart? i have that issue with my dart setup,... been through pulleys, alts and 23232 thousand belts

jnv255

Same problem here, after 9k it kicks it off

fukenricen

honestly , i noticed the problem slowly going away after i switched to a shorter belt and better quality

The sweed

What about making a guide of a timeing belt tensioner or some thing that just touches the belt on the middle.. That might help.. I am guessing the belt gets in resonance or something and a guide like the ones endyn and vibrant makes for the timeing belts should fix that on an alternator belt too..

fukenricen

actually your right on the money "The Sweed" , joe@altech is going to help me customize one for that belt using an old bseries tensioner pulley. we built one on my all motor h out of the same thing but for the timing belt and now i believe vibrant makes them.

pepeb18c

I have the same exact problem, but lately ive been flipping it instead of tearing it up.