A head question
Race Director
Joined: May 2005
Posts: 10,674
Likes: 121
From: Millington Illinois
St. Jude Donor '08-'09
With 58 to 64 CC heads your dish pistons are fine. I would find out the manufacturer of the E-bay heads. That info is not listed. The ZZ4 heads will not flow as well as the vortecs but provide better compression, weight savings and allow a higher DCR (smaller duration cam). The ZZ4 has 58 CC chambers, The vortec has 64 CC chambers. The ZZ4 heads respond well to porting. David Vizard talks about this head extensively, as well as porting instructions and pictures, in his book "How to Build & Modify Chevrolet Small-Block V-8 Cylinder Heads (Powerpro Series)". If you are handy and the price is right I would look at the ZZ4 head. You can get the intake side to flow as well as a stock vortec. The exhaust port flows well as is. The VC and Intake are standard bolt pattern. These will get you 9.5 to 1 with the thin head gasket.
Race Director
Joined: May 2005
Posts: 10,674
Likes: 121
From: Millington Illinois
St. Jude Donor '08-'09
Here is the porting info I had saved to my favorites. 
" GM's zz3/zz4 crate engines respond well to cylinder-head mods and a hotter camshaft. Looking at the heads first, the corvette-style aluminun castings have lots of potential when properly reworked. Avoid hogging them out; this is counter productive and in fact will probably break through the water jacket. You can keep the existing 1.94 intake and 1.50 exhaust valves.
On the intake side, concentrate porting efforts in the throat and valveguide area. One side of the port is closer to the guide than the other side; port to equalize the area on each side of the guide. Streamline the guide itself. Open up the port where it pinches down to get around the pushrod hole. Up to .050 inch of material may be ground off the "pinch" without breaking through. Properly reworked, the intake side should flow 225-230 cfm at 28 inches of water.
Use a similar technique on the exhaust side: The short-turn radius and throat area need to be Widened, radiused, and straightened so that it's dimensions are within 88% of the valve head diameter. Clean-up the exhaust port overall, raise the roof slightly, and open up the pushrod bulge. Properly reworked, the exhaust side should flow around 185 cfm at 28 inches water. The best results will be achieved by a competent shop that has prior experience on these heads..."
p.89, Car Craft, December 2000
If your careful and take your time and buy Vizards book you can do this yourself with good results.
" GM's zz3/zz4 crate engines respond well to cylinder-head mods and a hotter camshaft. Looking at the heads first, the corvette-style aluminun castings have lots of potential when properly reworked. Avoid hogging them out; this is counter productive and in fact will probably break through the water jacket. You can keep the existing 1.94 intake and 1.50 exhaust valves.
On the intake side, concentrate porting efforts in the throat and valveguide area. One side of the port is closer to the guide than the other side; port to equalize the area on each side of the guide. Streamline the guide itself. Open up the port where it pinches down to get around the pushrod hole. Up to .050 inch of material may be ground off the "pinch" without breaking through. Properly reworked, the intake side should flow 225-230 cfm at 28 inches of water.
Use a similar technique on the exhaust side: The short-turn radius and throat area need to be Widened, radiused, and straightened so that it's dimensions are within 88% of the valve head diameter. Clean-up the exhaust port overall, raise the roof slightly, and open up the pushrod bulge. Properly reworked, the exhaust side should flow around 185 cfm at 28 inches water. The best results will be achieved by a competent shop that has prior experience on these heads..."
p.89, Car Craft, December 2000
If your careful and take your time and buy Vizards book you can do this yourself with good results.
Last edited by 63mako; Apr 2, 2011 at 10:50 AM.
Le Mans Master
Joined: Jan 2006
Posts: 8,244
Likes: 114
From: Watkins Glen NY
Thread Starter
Burning Brakes
Joined: Feb 2011
Posts: 849
Likes: 0
From: Woodland California
This is what I ended up with, ZZ4 ALUMINUM HEADS.
http://cgi.ebay.com/ebaymotors/ws/eB...=STRK:MEWNX:IT
After weighing everything I know about Chevy this is the way I decided to go. Thank you 63 mako
I don't know what cam to go with let alone which cam.
Here are a couple of cams I've been looking at
http://www.summitracing.com/parts/SUM-K1103/
or the Edelbrock,
http://www.summitracing.com/parts/EDL-3702/
I know the ZZ4 is a roller cam engine and I'd like to stay close to the power it put out
with a Hyd. cam.
The engine must run my power brakes, run an air conditioner in traffic and I'd like use my stock torque converter.
Although that is a want not a must.
I've always been pleased with Edelbrock cams and manifold combos but someone here said this Summit cam was a good one.
Okay Q-jet or spread bore?
I had a performer on a Mopar 360 it was easy to dial in and trouble free.
Anything else going through your mind please let me know.
http://cgi.ebay.com/ebaymotors/ws/eB...=STRK:MEWNX:IT
After weighing everything I know about Chevy this is the way I decided to go. Thank you 63 mako
I don't know what cam to go with let alone which cam.
Here are a couple of cams I've been looking at
http://www.summitracing.com/parts/SUM-K1103/
or the Edelbrock,
http://www.summitracing.com/parts/EDL-3702/
I know the ZZ4 is a roller cam engine and I'd like to stay close to the power it put out
with a Hyd. cam.
The engine must run my power brakes, run an air conditioner in traffic and I'd like use my stock torque converter.
Although that is a want not a must.
I've always been pleased with Edelbrock cams and manifold combos but someone here said this Summit cam was a good one.
Okay Q-jet or spread bore?
I had a performer on a Mopar 360 it was easy to dial in and trouble free.
Anything else going through your mind please let me know.
Last edited by Ralphbf; Apr 4, 2011 at 04:28 AM.
