1. I recently purchased a 4lb interchangeable lower pulley for my lightning and I was trying to find out what belt size I need for it. The person I bought it from said that it was "NAPA Part# K080680" but I was unable to find this on their web site. Is this the same as a Gatorback 4080680?

2. I have a DiabloChip but I am trying to get a Superchip. Should I get a chip installed at the same time or will the stock program run fine with the new pulley?


Thanks for any help anyone can offer.

 

1. Yes. It's a 68.0" 6 rib belt. some people say you can go 67.5" ...but you may have to modify your tensioner to accomodate it.

2. You should be able to run a 4# lower w/o a chip TEMPORARILY. It's best to get it tuned and stay out of full boost until you do.

 

Buy an Sct 9100, with that programmer you get 3 custom tunes and with the software you can download future tunes. Best bet would be to talk to Mike Troyer.
I also run a 4lber w a 68" GB. I would have to look again but I believe mine is an 8 rib.

What year is your truck?

 

This topic has been beaten to death. Without any exception that I can recall, the stock tune has been fine with a 4 lb pulley. People have run 4 pounders without chips for years and tens of thousands of miles.

I would rather run a 4 lb pulley with the stock tune than with a mail-order chip.

 

My truck is a 99. The only reason I asked about the chip is that I want to do one anyway, and there are people locally who can tune them properly. I just wanted to know if it was safe to run it for a while without a tune. Thank you for answering my questions.