Getting the belt tensioned right seems to be almost an art. I'm in the middle of that 'art' right now on a kit I installed a little over a month ago. It's a nice kit, on the whole. As others have said, the instruction book provided with it is very nice. There's been a little more futzing around and finagling with this kit than I ever had putting an HKS centrifugal S/C on my BRZ. It just worked, first time, right out of the box. But, the kit on my '02, is getting better, incrementally. Teething issues, I guess.

Don't they have an auto-tensioner? What is making is so difficult to adjust?

They kind of have an auto tensioner. Yes, there is an auto tensioner on there but when tightened to the trackdog instructions the tensioner doesn't actually do much. In my opinion, the auto-tensioner should be mounted about 10 degrees counterclockwise from where it is presently mounted. When the manual tensioner is sufficiently tightened, the auto-tensioner is only moved a few MM from its fully lacking tension mode meaning those few MM are doing almost nothing for actually keeping tension.

This is trackdogs test fit photo.
https://cimg0.ibsrv.net/gimg/www.mia...5e160308be.jpg

True. There's a manual tensioner that has to be set. For the NB, you set it to 6 mm belt deflection at 20 lbs pressure...approximately. I say approximately, because good luck getting any sort of tension tester in there to check your work. I've been using the old Honda method of: twist the belt and see if it will 'just' twist 90 degrees, and if it will, you're good. If it twists further, it's too loose, if it won't twist 90 degrees, it's too tight.

The real fun is in getting your hands on the TDR-recommended Gates Green Stripe K040520 belts. Gates, in their infinite 'wisdom?' gave both the basic, cheapo belt and the Green Stripe the same part #. None of the local parts stores here can get them. The one that came from eBay, with a rubber band wrapped around it, looked like it had been hanging at the back of a bus warehouse on a nail for ten years.

I threw caution to the wind this past weekend and bought the Continental-brand equivalent. If appearances are anything, it looks to be a super nice belt. I installed it, tensioned it, idled the car for a few minutes, then re-checked tension. Took it for a drive, no belt explosion and what's more no CEL so far (from another un-belt-related issue).

I can get you a part number on what works for me. I use the 75mm pulley so I couldn't use the recommended/included pulley. I think it is the gates k040500 belt but I will double check when I get home. I think you can get what is known as their "RPM" line of belts that stretch less and should provide more tension and are supposed to be better for supercharger applications.

You also still have a/c, which is a factor in belt length.

I've got a 95mm pulley on my setup. I endeavored to order a Gates RPM belt and they didn't make a 520 equivalent. They had a 517 and a 530 I believe. So, they danced all around the size. I ordered the 517 as it was supposedly only 9/16" shorter and the 530 was a little over a half inch longer. The 517 would sooner have amputated my fingertips than fit. It was 9/16" too short, for sure. At 60 bucks a pop, I'm reluctant to get the 530 for fear it will fall outside the range of adjustment and I'll have $120 worth of belts I can't use. lol

Ahh right you are. Yes I do have AC and I am running their 4 rib setup.

*peers in*
*whispers*
I enjoyed the Rotrex-equipped NC the most out of everything that FM had in their garage, except perhaps the Catfish.
*disappears*