I was able to disconnect my passenger side pcv hose and re-route it. No more kink.

Isn’t the 2.85” the 9lb pulley? Wasn’t your old pulley the 8lb? Crazy numbers you’re making me want to say hold the phone and throw on the 2.85” but wanna make sure everything is kosher first. Tuning for flex but I plan to run e85 90% of the time but i guess it’s that other 10% things get dangerous

The 9lb pulley goes on the jackshft on the serpentine side. The stock serpentine jackshaft pulley is 8lb. The 2.85 is installed on the supercharger.

I'm running flex. Same thing, e85 90% of the time. The only time I'll be on 91 octane is if I take a trip and e85 isn't available. Seb pulled a bunch of timing on my 91 tune (for safety) and and primarily set me up to make all my power on e85.

Can you guys give the part numbers or link for the pulleys that you picked up from Vortech? Or let me know how you communicated your needs to Vortech. I want to change up my pulleys now for the high traction design given my lower-than-expected boost issue to see if that might help. The CRC dressing got me .3 more psi haha

I saw this one, Part# 2A038, on the Vortech website. It is the same part number for the "normal" 8-rib supercharger drive pulley and the "high-traction" pulleys...

The high traction category doesn't have a 3.4 option... Otherwise, I'd go back to the 8lb serp side and do the 3.4-3.0 jackshaft-SC on the SC side like Topz

I was thinking of keeping the 9lb serp side and ordering two 3.15 (is this what y'all are calling the 3.2?) high traction to replace the SC side.

And to answer the question, you might as well replace the belt, knowing that you've worn the belt a bit and having everything apart.

I'm replacing my jackshaft pulley with the 2A038 high traction 3.15 as they don't make a 3.20. I don't know what manufacturer the stock jackshaft pulley is but it's not a Vortech. Also, if you change your jackshaft pulley to the Vortech, you need to add a spacer to the sc shaft as the Vortech pulley is a different offset than the stock 3.20. 928 Motorsports makes a high traction 3.25 that looks pretty interesting but it's $180.00.

I already have a new belt ordered.

If I get a pair and replace both the jackshaft and the SC pulleys with the 3.15 (or smaller) High Traction from Vortech, won't the offsets match?

Nope. I installed a Vortech 2.85 sc pulley and it lines up fine with the stock jackshaft pulley. When I change my jackshaft to the high traction Vortech I'll have to add the spacer. FYI, 928 Motorsports carries the spacer, it may need to cut to length. Also, you'll have to use a longer bolt on the Vortech jackshaft pulley as it's wider than the stock pulley.

Stillen didn't use a Vortech pulley for the jackshaft, it looks like a Magnuson but I'm not positive.

Interesting...

Thanks for the info!!!

I'm not sure my tranny is ready for that much boost haha. Or me ready to spin the Vortech bearings that fast haha. But since I'm swapping out the pulleys anyways, I might go with the 3.15 jackshaft and maybe the 3.0 SC...

Per the Vortech calculator, I'm at 55.6k RPM now (with the serp-side 9lb pulley). Bumping down to the 3.0 while keeping the 3.15 ~stock size jackshaft would put me at ~58.4. Strongly debating stepping down the size since it'll keep me in the limits of the tranny.

If I had the 928 Supervortech upgrade, I'd go 3.47 jackshaft and 2.85 SC, which would spin it ~68k!

Did you just source the longer bolt from Lowe's or similar? Did you increase the SC-side idler?

Thanks again!!

I know I'm over spinning the Vortech bearings, I'll see how long they last. I might buy a spare V3 Si and send it to 928 for the bearing upgrade just in case.

I haven't gotten the bolt yet, my pulley won't ship from Vortech until next week. I have the 3" idler pulley installed.

I went ahead and picked up some high traction pulleys today. Where did you guys get the 3" smooth idler from for the SC side or what did y'all do instead? I thought someone just custom fit a nut in there or something that allowed the stock idler to move up further.

Thanks!

I think I saw a post where someone did do the "nut" thing but why not spend $25.00 and get the Gates #36225 idler pulley.

If you are going with the A2A upgrade from a stock Stillen kit and go the 9psi route you will need my kit to prevent belt slippage. You will be driving the supercharger with about 60 hp and the belt will slip. Some have been slipping at 8 psi.

The stock Nissan belt tensioner will take up the slack of going to a smaller jackshaft pulley (Stillen 9psi) but the contact area of the drive belt goes down and that will cause slip, Add in the extra load on the belt to drive the SC faster and more slip.

To try and keep things simple, the serpentine belt is the main drive belt and is a long 7 rib belt that connects the crankshaft pulley to all of the other main drive pulleys (including the supercharger jackshaft).

The other belt is the supercharger drive belt (small 8 rib belt) that connects the jackshaft to the supercharger. You can get to 9psi by replacing the SC pulley with a 2.95 inch pulley from Vortech (part number 2A038-295). If you go that route the drive belt tensioner will not have enough adjustment range to take up the belt slack due to the SC having a smaller diameter pulley. To fix that you will need to replace the idler pulley on the SC drive with a 76mm (Gates 36225).

I'm running the 2.95 Vortech pulley along with my extra idler pulley setup and am getting close to 9.5 psi. YMMV

Great info being passed along here. Thanks guys.

Speaking of your kit. Thought I'd share what I found recently. Don't know if you recall but I mentioned that I had an unusual loud whining noise after switching to your kit. Turns out some parts of the belt had sections of the sepertine teeth missing.

I ended up checking all idlers, 2 of them had bad bearings, 1 was atrocious and probably the reason for the noise (it was the smooth idler, not the 2 grooved ones). Could this have caused the damage with my belt or did the belt make the bearings worse?

Also, since as of tomorrow I'm a Boosted Performance Snail member, the SC kit is for sale, but I'd like to replace the belt for the unknown buyer. What is the belt model?


Cheers,

Sorry you are having a problem.

Your serpentine belt is badly damaged! Do not run it like that.

All belts that I deliver are modified by cutting off one of the ribs converting an 8 rib belt to a 7 rib belt. This modification is done using custom tooling and every inch of the belt is inspected before I modify them.

It looks like you had a idler pulley bearing failure that in turn damaged the belt.

The SC belt is a K080220 from MAGNUSON SUPERCHARGERS GATES MIRCO-V AUX BELT REAR 8-RIB Gates K080220 [M-79-08-02-020] - $42.00

If you need another serpentine belt to replace the damaged one, PM me.