I hear you Chris, I would call just call Mike @ NST rather than PMing. The belt with the part number you listed above can be acquired from Autozone as well :tup:

Use the Gates belt, whichever model number (length) NST recommends for your setup. Gates is good quality stuff, and they're generally available from local auto places, although sometimes they have to order them from a local dist center (a few hours, or a day at most).

Just ordered this belt from O'reilly's. Cost me $50.

What is the belt number so I can go pick one up this afternoon?

Well the K070776 is what I used because I have a mixed pulley set (NST's OD alternator + my old Stillen UD crank that I had already installed ages ago). It's the same one you use with just Stillen's UD, and was still in range.

NST seems to recommend K070786, which is a very slightly longer belt (and their UD pulley is a little bit bigger, so that makes sense).

Check the belt tensioner's marks after install and you'll know if everything's kosher on belt tension (service manual page EM-13).

Ok so instead of searching all 29 pages and 400+ post has anyone had any negative issues with these kits? I'm interested but my local performance shop who is very very experienced with cars in general but mostly the VQ series and they have warned me not to install a pulley kit on my Z.

Same here, heard various rumors of not to install these with an S.C kit. And a few others saying not to do so... any truth to it?

Well, with a Supercharger, you shouldn't use an underdrive crank pulley, as it underdrives the supercharger (although I guess you could make up for it by using a custom overdriven SC pulley to match, but it would be simpler to just run the stock crank pulley size). You could run a lightweight normal-sized pulley though.

The other argument (unrelated to superchargers) is about whether our crank pulley provides some sort of necessary harmonic balancing function for the engine internals, and thus replacing it with an aftermarket lightweight variant (underdriven or not) would lead to earlier engine failure because the crankshaft will vibrate funny and tear things up.

All I can say definitively about that, not being a Nissan engine designer, is my very lightweight Stillen underdrive pulley has been on my car for 18K miles and a lot of hard runs, and I haven't seen any ill effects yet.

This was debated in depth in a Stillen pulley thread. In the end I chose to believe the side of the argument that says the pulley is fine on this car, but it's easy to see how some people would be cautious or confused on the subject. Read the whole thread here, especially starting 2-3 pages in: http://www.the370z.com/engine-drivet...nk-pulley.html

I guess thats my problem because I ordered these, and would really like to install them. But I do hope to one day go S/C. I just don't know When that day will be... So do I install it and enjoy it now up until I go FI, or do I leave them off to save myself the cost of installing/uninstalling them... But having parts sitting here collecting dust... :confused:

I wouldn't worry about it. Taking off your UD pulley is like 1/1000th the labor of installing a supercharger, just be sure to save your stock one.

I guess since I don't have the belt, I'll just hold off on it. Maybe get a set of Stillens and have them installed at the same time since the front bumper will be off anyways, I'm guessing that might help with the install... or no?

Well, it certainly saves a little time wasted on lifting the car and removing the undertray, but the bumper doesn't affect things much for the pulley install. What would make the pulley install easier would be removing your radiator + core support, but unless you already had plans to upgrade your radiator, it's kinda overkill :).

Other than the tricksy bit of actually getting the crankshaft bolt loosened the first time, the pulley install is really simple with the right tools in hand.

Sweet, that is not bad at all! I will call Seb at SpecialtyZ, he always has amazing prices.

Thank you for the recent feedback and comments ladies and gents.

Pulleys are in stock and ready for immediate shipping. Red and Gray.
Belts are unfortunately on back order at this time, but should be available shortly.

As always, everyone is welcome and encouraged to contact us by phone for any reason.
281-917-0221.

MIKE @ NST

This is the only concern I have. Any experiences?