The standard 8 rib belt wouldn’t work with the 3.47” jackshaft and 3” supercharger pulley? Thought that was kind of standard setup.

I didn't have to change my belt when I went with that combo. Did you get your bpv silencer?

When I tried this combination... we found fitment issues for it and needed spacers or something IIRC.

So we only used the 3.0" pulley and didn't use the 3.47 or maybe it was the other way around, can't remember.

If you change the jackshaft pulley on the sc side then you have to add a spacer to the sc pulley and idler pulley. The stock jackshaft pulley that Stillen used isn't a Vortech pulley and has a different offset.

^ That was the issue. xD Yup. Haha.

@Redondo.

If I wanted to use a 3.0" and 3.47" pulley combination, which pulley spacer kit would I need from the photo attached from 928motorsports?

And these kits would work for like a 2.85" as well or nah?

I ordered the kit which came with the spacer that had to be cut because I didn't know what what the offset difference was. I'm not sure what the thickness of my spacer ended up being, I never asked my installer.

Yes, they work with the 2.85 also, they are based on shaft diameter, not pulley size.

Gotcha.

I'll order the spacer then because I know I'll be needing it in the future for whatever blower I end up getting.

It's good to know that the kit is based on the shaft diameter and not the pulley size.

Since we both have the same brackets, then I should be in the same boat as you.

Thanks!

Yep, definitely in the same boat. 😁

Since I blew up my belt.

I purchased this belt:
K080220

as a replacement.

This belt will be good enough to fit 3.0" jackshaft SC, 3.47" pulleys?

What belt part number do you have to fit your current 3.0 and 3.47 setup? assuming i had spacers too

That's the correct belt, it works fine with with the 3.47 jackshaft and 3.00 sc pulley. The spacer has nothing to do with belt length. Gates does also make a heavier duty belt. The part number is K080220RPM. It's specifically made for forced induction.

Oh I saw that one too. The K080220 I just didn't know if that was better or worse than the one that I ordered.

Maybe I'll order that one too just for kicks. I mean can never have too many belts right? Haha. I'll thank myself later if I ordered extra belts!

#F.I.Life

Sweet. Cuz I was told by someone on the forum that if I went different pulley sizes I would need a different belt size which was tripping me up cause there's so many options for belt sizes out there T_T

G'thing you shared this information with me.

I appreciate that bro!

On the supercharger side if you change pulley sizes the only thing you might have to change is the idler pulley size, not belt size. I have the 3.47 jackshaft pulley with the 3.00 sc pulley. I'm using the 2.50 idler pulley. If I went to the 2.85 sc pulley with the 3.47 jackshaft I'd probably change the idler to a 3.00.

Okay.

So what I'm getting from this information is:
Total area the belt surrounds with your current setup of:
- 3.47 Jackshaft SC sided pulley
- 3.00 Direct SC Blower pulley
- 2.50 SC Idler pulley
---------------------------------------------
Total: 8.97" inches of area that the pulleys are using up from the belt and it seems to work fine.

Then you said if you changed the 3.0" down to a 2.85" Direct SC Blower pulley, to compensate for the loss in size, you have to change another pulley and that pulley of choice would be your idler size -- and to upgrade it in size at that which you said a 3.00" idler pulley would do it.

This would give you a total of 9.32" inches of area that the pulleys would use up as opposed to your previous setup of 8.97".

I assume the idler pulley could be adjusted to compensate for the difference of .35" of area between the two setups?

Yes, the Stillen bracket has a tension adjuster for the idler pulley.