Changing the Belt Path
 

I'm thinking about buying an L36 SC Kit from ZZP, and I was looking into how to increase belt wrap around the SC pulley, since it won't be routed like a Grand Prix with a secondary belt. I don't know much about changing the routing of a serpentine belt, but I was thinking I could simply bypass the AC compressor pulley (since I'll be deleting it anyway), and the additional idler pulley the SC kit comes with, in order to wrap around more of the SC pulley.

https://cimg5.ibsrv.net/gimg/monteca...cdb75261ce.png
^The way ZZP's instructions depict the belt routing w/ secondary idler pulley on the right
https://cimg4.ibsrv.net/gimg/monteca...b56f7d040e.png
^Propossed routing which "should" maintain tension from the stock idler pulley/tensioner on the left
https://cimg6.ibsrv.net/gimg/monteca...1fa04678bb.jpg
^Grand Prix belt routing with two belts

I do already have a concern about the routing I've proposed. It looks like the belt wouldn't wrap around enough of the power steering pump to keep it functional.

Curious why you're looking at that kit? It's extremely expensive for what it is just to help save a little time on install labor. It's also very limiting as they dont make below a 3.4" pulley for it (as you noted, due to belt slip issues). But you could buy a whole L67, or heck even a whole GP GTP for what that kit costs.

If you're dead set on it, there's no reason to delete AC and reroute the belt though. People have installed that new idler provided in the head hole (on the front head) closest to the water pump which brings the belt fairly close to where you'd be looking to move it to anyways. That's been fine for a 3.4", you'll just need a little longer belt.

But IMO, I'd just skip that kit and do a normal top swap.

I've had a pretty good experience with the things I've ordered from ZZP (high voltage coil packs, shorter dog bones, 3" downpipe, etc.), and the customer service is consistnely some of the best I've delt with. (I ask a whole lot of questions about their products.) Really, convinience is the main reason I look at ZZP's products. With the SC kit, everything is plug and play, right down to the ECU changes.
In the product description for the SC kit, it states you can run the standard pullleys for the SC if you swap to the GTP balancer and accessory pulleys.
I know nothing about doing a top swap. Feel free to educate me if you'd like, or post a link for me.

Doing a 'top swap' (I hate the name btw as there is more involved, but that's just the term that all the search topics are under) is basically taking all of the supercharged parts off a L67 and putting them onto an L36. That includes the heads, LIM, blower, fuel rail/injectors, TB, and front drive stuff.

The big selling point of the ZZP kit is that you dont have to do the labor of swapping the front drive stuff or the heads. My problem with their kit is that the cost is insane nowadays. People have pulled off top swaps for under $500, this kit is more than triple that all just to save a little labor. Plus, unless you swap the front drive stuff as mentioned, you're stuck with a 3.4" or bigger pulley.

I totally get the point of the kit 10 years ago, but with these engines being a dime a dozen in the junkyards, I just dont see how the financial sense works out anymore. A top swap or complete L67 swap is the way to go. If all the labor is a big concern, another option is a turbo kit. Sure it's more $ up front, but you'd make a lot more power than this kit would.

The reason I'm looking into adding a SC to my L36, is because even though I know it's completely impractical/inefficant, I've been entertaining the idea of twincharging the engine. Although seeing how much I'd have to change with the engine, I'll probably just turbo, or twin turbo it.

Top swap or turbo. Screw that overpriced zzp l36 sc kit.

Its not that twin charging is necessarily inefficient, it's just that it's not beneficial enough to be worth the hassle IMO, especially not having a supercharged engine to start with. Plenty of people have done it on the M90 / 3800 though so there's plenty of reading out there if you're serious.

Personally, unless you've just got money to burn, I'd put that $2k for the zzp m90 kit towards buying a real turbo setup and see how you like that first. You can always come back and add a blower later, but the bang for the buck for horsepower will be with the turbo.

If you're worried about it not leaving off the line hard enough (since you're considering a blower also, I'm assuming that), just dont go nuts on turbo size, get a modern turbo, and drop in a higher stall converter. That'll be more than enough for street tires.

IMO twins aren't really worthwhile either. The main issue is that there is no twin kit, so it would be a completely custom fab job (ie big $$). The second issue is packaging space. The big benefit of a TT is getting the turbos smaller and closer to the head to light them off faster. With the tight engine bay, you're not going to be able to get them much closer than a single would be without monster fab work.

I do totally understand wanting to get it spooled up faster, but IMO thats not very helpful on a platform like this. It's hard enough to hook a good 400 or 500+ whp turbo w body off the line - getting that power up to full blast say 1000 rpm earlier is just going to blow the tires off sooner in 1st.

Yeah, I know getting traction is going to be the most difficult part. In regards to a turbo kit, ZZP has two. The basic Z3, and the high end Stattama. Would it be worth saving up for the higher end kit, or would you recommend not going with ZZP for a turbo kit?

What's your power goal and focus of the car (more street, more racing)? For a more drag focused car going for big power I'd rather have the Stattama, but by the time you add fueling, meth, and a built trans, you've already dropped $10k. That probably doesn't make much sense for a more budget oriented street car.

My goal is a bit ambitious. I'm hoping to get to 500 WHP, but I know my limitation is going to be the trans chain. I'm also going to have the engine rebuilt with new bearings, rods and pistons to bring the compression down, and a cam.