LSxSprayed

I have a simple set up. If your standing infront of the car and looking at the engine bay i have my manual tensioner on the top left of the water pump, stock ls1 waterpump, and my alternator which bolts directly to the block in the bottom right of the block and then of course the crank.

I don't know how to keep it from slipping during a pass under WOT it slips i can tell because my voltage drops a lot like 3 volts. Alternator is good I know that, if i do a slow acceleration and climb to 7k rpm it will stay at 14.5 volts but under load it drops to 11ish.

I tried VHT and cranking down on the belt tensioner but one time the bolts that hold the alternator in broke off but still slips.

Any ideas on how to not get it to slip, dropping voltage with 2 nitrous and 2 fuel solenoids is scary sometimes lol

S10xGN

iTrader: (11)

Buy a good quality belt. I've got a complete C5 FEAD plus A/C riding on one belt. I did have to add a manual tensioner, but it never slips.

Darth_V8r

iTrader: (4)

Electric water pump, tensioner delete, jegs adjustable alternator mount, short belt.

9...10..... never slip again....

Yes 80's horror flick reference

LSxSprayed

I was thinking that but I want to retain my heat

Darth_V8r

iTrader: (4)

If you haven't already tried a continental extremes -- the old gatorback -- might be worth a shot

Majestic9C1

iTrader: (19)

try a tensioner pulley with a lip on the edge ( GM 3.8 idler pulley)

LSxSprayed

i tried a gator back and 3 different belts. I think the issue is the belt is making contact with a small portion of the crank given the tensioner is in the top left and the alternator is in the bottom right

Old Geezer

iTrader: (3)

Drive ratio on the alt?
Could the alt be over rev'd to cause output drop out?
Do you see belt dust scattered around?

LSxSprayed

I forgot what i changed it to, I was over revving it. I did the math on it but i forgot what it all was. I think it was 2.25 then i changed it to 2.5 on the alt pulley. like i said before if I do a slow pull it will be fine and not slip but if i hit it hard it will slip at 3-4k

Fullpower

I had some belt slip on decel, audible screech at 1-2 shift, or closed throttle from high rpm.
resolved by changing alternator pulley form OEM 2.2" to a 2.6" pulley. no other changes required, and it still produces 110 amps at hot idle.

00pooterSS

iTrader: (40)

Same as a stock setup and slip can be fixed with those.

Don't spray any sort of belt band aid goo on the belt. It isn't going to help. Try a fresh belt, any brand should do, i've used gatorbacks to stop squeaks but a regular belt has more surface area to grab since there aren't slits in it like the gatorback. And tighten it more.

The high wall pulley helps keep from throwing the belt but it doesn't help the belt grab. I've used those before on my car when I had belt slip and throwing the belt, it'll still slip. You just need it tighter and the belt you currently have may be the issue. If it's older the rubber may be hardening a bit and you sprayed goo on it, so it needs to go for that reason if nothing else.

When you get the new belt clean all the pulleys real well with brake cleaner to get any goo off of them and make sure they are clean and dry.

Are you cranking on the tensioner with a short (6" or so) ratchet? If so get a cheater bar on it or use a 1/2" drive. Don't go crazy with cranking it down just make a mark where you've been getting it to go to with a marker on the tensioner and then use a longer ratchet to take it just a hair further. With the new belt, you'll need a slightly different technique since it will be a hair shorter than the current belt (not stretched yet). Put it on, crank on it like you have been doing, make a mark, then get a longer ratchet and take it just a hair past that mark and try that and see how it works. If you need it a little tighter make another mark and take it just a tiny bit past that. Don't just go crazy cranking on it with a long ratchet.

LSxSprayed

Bringing this back from the dead. I got this set up


like i said before i dont think there is enough contact with the crank. I get that the stock set up is similar with surface area of contact but im shocking it all with a decent hit of nitrous.

I have a manual tensioner that did help but it just slips the belt at a slightly higher rpm. I get it very tight but still slips. Any other ideas/suggestions?

RB04Av

I don't see any way in Hades that's ever going to work, as-is.

There needs to be an idler on the driver's side. Then, following belt "pull", you could route it crank ->WP -> alt -> idler -> tensioner -> crank. And hope it misses the water outlet. Still leaves YUUUUUJJJJE lengths of belt just flopping around out there in free space though.