Hi All,
I've got a ZZ4 w/ no mods and I'm looking to increase substantially from the 355hp. I was considering pouring the money into my BB but I've been reading more about superchargers lately and I'm reading advertised gains of 150hp for only a few thousand $$'s. However, they also recommend compression ratios for the most part around 9:1. The ZZ4 is rated at 10:1.

Anyone ever tried this? Am I just going to blow up a pretty solid mill if I strap a supercharger on it?

Dan

 

Whipple makes a ZZ4 kit.

 

If your engine lives, let me know and I'll try it on my C4 (W/ZZ4).

Seriously though I was looking at a chart the other day and off the top of my head, with static 10:1 CR, you are going to be looking at about 13.5:1 or higher with boost. You are going to have severe detonation. Maybe the ZZ4 knock sensor will dial back the timing and save your cast pistons, but I wouldn't bet on it.

I know where you are at, the ZZ4 is nice, but really could use a little more power. I've thought on this a while. Really the safest bet is cam/head upgrade, but thats not cheap and its a PITA. (although if your buying a new blower, thats not at all cheap either, heads and cam might be cheaper)

Now, there are a hell of a lot of guys spraying (NO2) relatively high compression engines with cast pistons over on the C4 FI board, but Im not even sure Im comfortable with that. I think most of them are no higher than 9:1.

in my OPINION, the only way to go boost, is with all forged internals. Even then you're not completely safe- I broke a forged piston in my C3 with about 10 PSI. (at 8:5 CR)

Plus, read the direction sheet on one of those centrifugal blowers. Good god almighty- Ill strap a roots on and cut a hole in the hood any day

I think it said 20 hours by a trained professional, expect 2X that for DIY.

I just looked it up. 10:1 CR + 8 PSI boost = effective compression ratio is 15.24 :1

 

And they know that ZZ4s have 10:1. From what I understand, you'll get more low-end torque with a higher ratio and lose a little hp on the upper end. However, who cares when you're adding 40-50% more hp...

Like Droshki said, 8 - 10 psi max unless you rebuild the internals.

 

Well, I wouldn't even go 8-10PSI on top of a 10:1 compression ratio, unless I had some really strong internals. I guess the OP could call whipple and ask them how they dont think 15:1 CR is going to be a problem. I'm sure their optional intercooler would help, but I still think detonation is a reality without use of avgas.

I am going 8.5 CR on my current 383 build, which should put me at about 12:9 with boost, and I'll be using forged pistons, crank, and H-beam rods, and copper head gaskets and o-rings in the block to mate up with them.

I mean, seriously, if it works, let me know, I'd love to wake up my ZZ4 in my other car, but I'll let you got first

 

I looked into this a while back and found my way to ProCharger website...

I sent away for their free info kit and to my surprise found they made a kit specifically for the ZZ4... (I don't know why they don't directly advertise this on their website... if they do I couldn't find it...)

Anyways I'll copy down some of the specs from the brochure I received.

-ProCharger Kit: C2
-Intercooler: N/A
-Boost: 8 psi
-Engine: ZZ-4 Crate Motor (and specs associated with)
-Carb: 600 Holley (can come with kit- dyno tuned)
-Naturally aspirated HP: 355
-Est. PC HP: 497 (40% increase)
-Part Number: 1CD110-C2 or 1CD100-C2 (info from brochure is 1 year old)

-Article with a similar application (if not the same one with different part numbers- Here)

 

I know how you guys feel, I have a ZZ4 also and was disappointed with the grunt from it. I swapped out the heads for some Brodix IK-180's, put in GM's stroker cam and a Weiand intake. It really made a difference in the motor, I'm pretty happy with it now. It is some work to do all this but it isn't too scientific, just time consuming and of course costs $$. But if you weigh the cost, the head scratching involved and also the potential to mess up your internals, I think you're better off swapping heads and camshafts then going the blower route.

I agree though, it sure would be a cool project if it came out OK and was reliable.

 

Whipple just had a write up in Chevy High Performance claiming a high comp. eng. is OK with their new supercharger. Very $$$$ pricey but effective.

 

Fourth paragraph, first sentance: "and 100-octane fuel "

 

You cannot run a supercharger if you have cast pistons.Pistons are not strong enough.You "MUST" run forged pistons.

 

(Nobody did) but if you ask me, I think those companies are doing a disservice advertising a bolt-on to cast pistons and 10:1 compression ratio.

Sure you *can*...but...for how long?

I broke a forged piston with only 8.5:1 and 10 PSI

 

Dude, relax and keep reading.CHP(Whipple Stomp) The next graph shows 91 oct. and more power.

 

You guys are in for a rude awakening if you try to run that much boost with higher compression motors, especially with cast pistons.

Back years ago whin I was running superchargers, the rule we went by was no more than 12-1 dynamic compression ratio. The lower the static compression was the better because you could run more boost and still stay under the 12-1 rule.

Imagine a 433 ci big block with 5.6-1 static compression running 22-25 pounds of boost making ~1200 hp on the street.