This is from my first pass when I threw the belt at the top of first gear.
I was not at all pleased with my first trip to the track with the Procharger. It's been a week and I havent even looked at the slips until today. All runs after this sucked thanks to the belt stretching and slipping badly. On this run I started spinning around the 60ft mark or so, hit the rev limiter in first gear and lost the belt.

60ft---------1.7665
330ft--------5.0866
1/8mile------7.9328@ 83.69 (had already lost belt way before this-other 1/8 mile mph's were 88mph with slipping belt)
1/4---------12.8410@96.42mph(no belt, had lifted a couple of times, then let out completely shortly before the finish)

I guess what im trying to figure out, if I had had a clean run, would I have seen 11's in the heat. Temps were around 96 degrees on this run. All in all, I guess not all that bad considering the belt was lost at the top of first gear.
I have since made some changes that should keep it from throwing the belt should it hit the rev limiter again. I dont plan on running again though until it cools off some.
Any and all opinions welcome

 

Can't tell for sure, but I could see 11's as a definite possiblity. The concern I have is the mph(88mph 1/8th) and my fading memory aren't matcing up well. Generally speaking, that should be enough to go 11's with the right gearing.

Are you getting a belt with more ribs too, or just replacing the 1st one? Obviously, more ribs requires a pulley change, but it may be needed to keep the thing where it belongs. Back when I was far more into racing, we(where I worked) had a few cars that would lose the belt. We went to Harley Davidson belts and those worked pretty well for most cars.

 

I was trying a Dayco polycog. It stretched too easy and may not have been short enough to begin with. I just recently switched back to my belt of choice, a Goodyear Gator back. I got it short enough that I damn near could not get it on. I also switched tensioner pullies to an ASP LS1 pulley, it has slightly taller sides and should help retain the belt in the event of hitting the rev limiter which of course relaxes the tensioner. I know of one other procharged truck that did this and the pulley stopped his belt problem.

 

I think you've got it covered really. Dayco belts work fine, but most belt slippage is due to age or incorrect sizing no matter the brand. I lost a belt on a car w/o a S/C once. I immediately did what you did, replacing it with one that nearly wouldn't go on. That wasn't fun, but it cured the problem.

Now you can go find out if it will run 11's.