INTENSE vs. ZZP SC Pulleys

I recently acquired a 3.3" ZZP Pulley from oldsman105, and discovered a difference between it and my INTENSE 3.4". The two are supposed to be compatible, but they look very different. The ZZP has more mass (thicker), and the grooves are shifted inward compared to the INTENSE pulley:



INTENSE installed my pulley with the belt on the innermost grooves, leaving two empty grooves to the outside of the snout. I've since put about 90k miles on a single belt using this set-up, so this seems to be the correct way to install INTENSE SC pulleys.

But the ZZP SC pulley requires the belt be centered on the middle groves, with one empty groove on each side. I tried installing it like my INTENSE, but the belt was crooked. Here are 3 pictures I took showing the different alignments. You can see how the ZZP shifts the belt when mounted on the inner grooves:



These alignments were observed using an INTENSE mounting hub. Results could be different using a ZZP hub.

Nope that is the way it is supposed to be .

http://www.clubgp.com/newforum/tm.asp?m=3822325&p=1&tmode=1&smode=1

This should help...

According to that thread, no one knows which is correct. Half of those guys are running ZZP pulleys on middle, half run inside, so half of them are going to see premature belt wear.

It's pretty obvious to me that ZZP pulleys should be run on the middle grooves, INTENSE on the innermost grooves. The point I was trying to make is the two brands are different - ZZP's pulley grooves are shifted one to the inside compared to INTENSE. It's not a problem, just something to be aware of. You don't want to use the inner grooves on a ZZP pulley.

Actually on my car I use the inner grooves, thats how the belt aligned best?

I think a lot of folks are doing the same, but I don't think it's correct now after comparing the INTENSE and ZZP side by side. I don't know, maybe there are differences in our set-ups. Shouldn't be, though.

I would think there would be definite issues of belts coming off if misaligned by much. Could be also that some hubs aren't getting pressed on all the way to flush with the shaft? Dunno... seems they aren't perfectly interchangeable.

I'm happy to report that with my Pulley Boys mps, and the hub pressed on properly, the belt lined up perfectly, on the 6-rib SC pulley. It's running in the exact same spot on the idler pulleys as the stock setup.

my intense runs great on the inside grooves........

Update: I ran my INTENSE SC pulleys in the innermost groves for must of the summer months last year, then switched to the ZZP pulley and ran it on the center grooves for at least 6 months now. It appears the two types are different, and it is necessary to use different alignments with each brand. My belts are fairly new and appear to be wearing fine. No slippage or other problems so far.

any difference between slippage and boost numbers with the different brands? they both claim to grip better than the other... i'm skeptical to whether or not it would matter anyway unless you run a really small pulley like 2.8 at 7k rpms or something.

Yes, the ZZP gives +10 horsepower! Just kidding, the ZZP is just a smaller pulley.

There is no real difference... at least not according to the thread profiles like the two companies would lead you to believe. If anything, one would wear the belt differently than the other, but that's only speculation. I will say this: using an INTENSE pulley, I was able to obtain 90k miles on a set of belts with acceptable wear. Using the ZZP pulley, the track record isn't there, but I have seen no negative effects to belt wear or performance, and have no reason to suspect it is inferior in design. I intend to use both pulleys for as long as I own the car.

Realizing that you have an INTENSE mps hub and the pullies are "interchangable" have you considered that the hubs may be different to accomodate the difference?

I happen to have both hubs at home and this thought occurred. I can snap off some pics tonight.

Yes, you are correct that this could cause part of the problem, and I did consider it (see last sentence of first post), but no matter which hub you use, there will be an alignment issue when you try to fit the other brand pulley. Obviously, it would make no sense to use multiple hugs to remedy things.

I'm with you on the hugs.

Should be able to get those pics. I thought the ZZP one had a lip.

Lol, hugs... I meant HUBS!

So it's not Intense or ZZP, but using the Pulley Boys MPS not only looks better, but is less confusing. It's a 6-rib pulley and there's no mistaking which ribs fall where...

I don't ever see myself going to an 8-rib system, so why install an 8-rib pulley? I think it's ugly to have the 8-rib pulley if you aren't using all 8 ribs.

Also, Pulley Boys pullies are available in increments of every tenth from 2.4 to 3.6 plus a 3.8 (stock) pulley.

I do like the looks of Pulley Boys pulleys, I agree with that.

ZZP and INTENSE also use .1" increments. I bought an INTENSE MPS because they are located close to me and installed it for free. Also, almost everyone I've talked to at the track uses INTENSE or ZZP systems.

Almost looks like Pulley Boys would fit the same INTENSE/ZZP hub?

I don't know, the bolts are different for sure, it uses a flat head bold instead of buttons or hexs. The thread would have to be the same, and then the alignment...???

I might work. The PB bolts are countersunk, but they could screw into a ZZP or INTENSE hub.

The ZZP and INTENSE bolts are completely different, but the threads and alignment are the same. I switched to ZZP bolts because they are beefier and shouldn't strip as easily.

When using an INTENSE MPS system (multi pulley system) the belt is all the way to the inside of the ribs. When using a ZZP MPS system the belt is centered in the middle of all the ribs. Reason behind this is the belt is 6 ribs and the pulleys come with 8 ribs.

This thread spurred the question of if the MPS hubs were different thicknesses. They are ZZP hub is thicker than the INTENSE hub.

ZZP on left in all pics





Here's the thickness
INTENSE



ZZP



While the ZZP is thicker, the overall length of both is the same. If pressed on they should both be at the same place on the end of the supercharger snout. The difference appears to be in the pulley machining.

Well, that answers that. Thanks, Bill!

So, apparently there was a little bit of a controversy surrounding the design of Intense's pulley vs. ZZP's pulley.

Take a look here:
http://www.intense-racing.com/MPS/

and here:
https://www.zzperformance.com/grand_prix/articles1.php?id=44

What we have here, is a failure to communicate.

So, both companies claim that their pulley design is better, and their competitor is worse.

I'm going to be in Delaware in a few weeks (near Intense's headquarters), and I can get the free Intense MPS installation. However, that's the only deciding factor in choosing these.

Lately I've been trusting Intense more than ZZP, ever since ZZP screwed up my PCM and a few other things. I'm probably going to end up with a powerlog, but that's only because they've made countless corrections (that should have been done the first time around).

So... does anyone have the final word on this (family) feud?

I'd say they will both work just fine. I got Intenses because It looked cooler than the black one that I saw for ZZP. I mean it IS just a damn pulley.

I seriously doubt that there is any significant performance difference between the 2 designs, on a street car. I went with the Pulley Boys mps.

Belt slip isn't even an issue with the low boost levels the m90 makes imo... On a whipple or something it matters , but i doubt it would on our blowers. I went intense as it seemed to be a much better looking pulley system and when i got it i was impressed with how high quality it felt and looked. Im sure zzp isnt bad either though. And really i don't think the groove design makes much of a difference. That and the rivs belt routing provides a large contact area on the supercharger pulley.

Guess I'm going Intense.

I dunno. If the companies were making such a big deal about it, I figured that the customers were up in arms about something... oh well.