few questions about CNC porting ZZ4 heads
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few questions about CNC porting ZZ4 heads
Anybody here do it? I dont feel like spending over 1300 on CNC ported heads...hate to sound cheap. But since I'm in the market for heads, I thought I'd try to maximize flow on a set of heads, over the standard 260 cfm you get with a out of the box set of heads. Something like 280 cfm or more, and 210+ cfm on the exhuast. So I'm considering having a set of bare ZZ4 heads built up. larger valves, small intake runners, and have the heads max ported. Anybody know who can do this and for how much? Even better, what the flow numbers are? I can't come up with anything in my searches on this topic. It would be great to get a set of ZZ4's to run 280 cfm on a head that small and would be worth the money to me. I'm already running a cc306 roller cam and LT1 intake on my 11.5:1 383 so the power is in the heads now. If anyone knows I would really appreciate it. Thanks!
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Re: few questions about CNC porting ZZ4 heads
Originally posted by dhirocz
Anybody here do it? I dont feel like spending over 1300 on CNC ported heads...hate to sound cheap. But since I'm in the market for heads, I thought I'd try to maximize flow on a set of heads, over the standard 260 cfm you get with a out of the box set of heads. Something like 280 cfm or more, and 210+ cfm on the exhuast. So I'm considering having a set of bare ZZ4 heads built up. larger valves, small intake runners, and have the heads max ported. Anybody know who can do this and for how much? Even better, what the flow numbers are? I can't come up with anything in my searches on this topic. It would be great to get a set of ZZ4's to run 280 cfm on a head that small and would be worth the money to me. I'm already running a cc306 roller cam and LT1 intake on my 11.5:1 383 so the power is in the heads now. If anyone knows I would really appreciate it. Thanks!
Anybody here do it? I dont feel like spending over 1300 on CNC ported heads...hate to sound cheap. But since I'm in the market for heads, I thought I'd try to maximize flow on a set of heads, over the standard 260 cfm you get with a out of the box set of heads. Something like 280 cfm or more, and 210+ cfm on the exhuast. So I'm considering having a set of bare ZZ4 heads built up. larger valves, small intake runners, and have the heads max ported. Anybody know who can do this and for how much? Even better, what the flow numbers are? I can't come up with anything in my searches on this topic. It would be great to get a set of ZZ4's to run 280 cfm on a head that small and would be worth the money to me. I'm already running a cc306 roller cam and LT1 intake on my 11.5:1 383 so the power is in the heads now. If anyone knows I would really appreciate it. Thanks!
Search engine should bring it up if that isn't it.
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I'm just thinking, but even if you have the heads, by the time you get through with new parts and machine work, then toss porting on top of it, you're well on your way to a set of AFR's, etc....gotta figure in shipping both ways too.
Rereading you post, seems you don't have the heads yet...adds more cost and brings you closer to AFR's, etc.
Rereading you post, seems you don't have the heads yet...adds more cost and brings you closer to AFR's, etc.
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Engine: 350 LT1/382 LT1
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Well you're right, the price come close to if not exceed the price of AFR heads. But they flow 260ish cfm out of the box, and I'm looking for a bit more than that. I figured I start with a decent head core, CNC the entire set of heads, and I'll have an aluminum head that appears stock, flows awsome, and makes great torque...I doubt the head will still have a 163cc intake runner, but it certainly would make good torque and power. That's my goal. If the price isn't feasable, then I'll just have to settle for aftermarket heads and sending them out for porting.
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If you want to end up with a head that flows over 260cfm don't start with a factory L-98/ ZZ4 head.
Start with a Protopline 180 or 200cc head or a Brodix track 1
and port them.
You have to realize that the higher flow advantage will only appear at very high lift. Keep that in mind when you select a cam.
Start with a Protopline 180 or 200cc head or a Brodix track 1
and port them.
You have to realize that the higher flow advantage will only appear at very high lift. Keep that in mind when you select a cam.
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