Mike94ZLT1

iTrader: (3)

I remember this used to be an issue with LS1's, and it is something I DEFINITELY do not want to deal with on a C5. F-body, no problem you can change the belt from the top without jacking up the car. C5? Forget about it. I purchased a powerbond underdrive pulley for my new engine, and the last thing I want is it flying off. Should I buy something like a Katech billet tensioner to avoid this? I don't care to be stranded somewhere. Thanks!

TheBlurLS1

iTrader: (8)

I've never seen problems with it, but not too many 'vette owners post in here. Us f-bod guys usually run them out.

I'd try it without it at first, you probably won't have a problem. If you're a baller, go ahead and buy the Katech tensioner, you'll even have the pimp factor.

Mike94ZLT1

iTrader: (3)

I had 5 f-bodies before I had a vette Never had an underdrive pulley though, I was always afraid of this belt slipping problem. I have a 383 in the works, and I didn't want to reuse my balancer off my old LS1.

schultzsj

iTrader: (1)

I've run a 25% underdrive ASP for at least 4 years and have never thrown a single belt. The pulley is now literally coming apart but still no thrown belt. I wouldn't worry about it - I suspect that people that had this problem had other causes such as mis-aligned pulleys.

I really believe in 25% underdrive pulleys. Besides the added power, there is less wear and tear on your accessories and, in theory, better gas mileage (although the improvement would be negligible).

Steve