Hey Skip
I would like to know a little more about your Z.
How much does it weigh
Slicks?
Rear suspension?

Now back to the heads. I may give you a call and try to get one of those sets of Patriots. I wanted to keep the runners around 180cc.
If I had the money I would go for the AFR180 eliminators but I could use that $700 else where. It will be a 350 with the ZZ4 cam, 474/510 lift with 1.5 rockers but I want to run 1.6 rockers and dur is 208/221.

My real question is what process do the heads go through after they arrive at your shop.
Have you flowed them as they come out of the box and how much of an improvement does your shop make to them?
I think this will help educate some of our more sensible members.

For the rest of the members. If you have a specific question ask it in an educated manner and don't expext Mr. White to read your mind.

Semper Fi

 

Just passing by, and just wanted to express my respect to Skip for hanging in there.

Guy's challenge him technically, not personally and try to keep it civilized please.

Q: This higher flow numbers thing, how does that effect efficiency?

 

Nice to see you back again Skip!

I need your opinion about which cylinder heads to choose. I am looking for cylinder heads, which will give me highest possible flow speed, with less than 200cc intake runners, at 0.200 thru 0.400 lifts. I am not concerned about highest possible HP at WOT, I just want a descent torque in the range 2000 thru 4000 rpm. I would prefere to have comp. ratio less than 10:1 (Comp chamber : 70 -76cc)

For your guidance, here is my setup:

http://cgi.ebay.com/ebaymotors/CHEVY...QQcmdZViewItem

383CID (as per the engine builder: 360HP @ (asuming 4800 rpm) and 410 ft. lbs @ 3800, ….blue print)

CompCams XE-268H flat tappet

Static compression rate 9.6 : 1 (assuming; with 72cc compression chambers)
GM 458642 cylinder heads, 1.94/1.5 valves, modified valve bowls and seats (I have not verified this yet by visual inspection), 72cc chambers (probably grid off from 76cc). Assuming similar specification as GM 333882……. information for the GM 458642s is very hard to find! ….So this is more and less qualified guesses.

Edelbrock 600 CFM (have also a 1411, 750 CFM to be tested out if the 600 is too small)
Power Plus Cyclone intake manifold (have also an Edelbrock Performer to be tested out)

Long tube headers (1 5/8” to 3”)
Dual 2.5” with H tube close to headers (no cats or smog devices) and low restricted mufflers

L82 Vette (4 speed M/T and 3.7:1)

best regards
Arne

 

Hey Skip
I am always one for the underdog. That is why I am building an engine with the ZZ4 cam. With the aluminum heads that GM put on that ZZ4 engine I believe they are really choking a cam that can be VERY civilized and yet produce over 400HP and possibly around 430FtLbs TQ with the right heads and intake/exhaust. It will go in my 70 camaro which weighs at this time, 3200lbs and will run a 3:23 rear and a 5 speed with a 2.95 1st gear.
I wonder why chevy never ran the ZZ4 cam with the vortec heads? Probably because they would have made the aluminum heads look pathetic compared to cast iron vortecs.
The ZZ385(ZZ4 with fast burns) proves my point. 385hp, 385ftlbs TQ.(stock ZZ4 is 355hp(5250rpm), 405tq(3500rpm)) But those fast burns with 210 runners take a loss in TQ from 405 to 385. That is why I am trying to keep the runner size around 180 or so. to keep velocity up and TQ up.

My other underdog story is my 82 vette with the cross fire injection.
If I can get the computer to run the ZZ4 cam and add better heads and get the intake to flow better or replace it with a SY1 then I should be able to get the HP numbers up to where a vette deserves to be. The crossfire injection forum will help me with that.

Thanks for your time Skip

 

Skip thanks!

I want to check my understanding of heads.

High flow=more mixture=more HP/TQ (theoretically)

 

Can you belief that at a gas price of 1.25 euro/liter is about 6 dollars per gallon. Crazy prices over here.

Tractor pulling is big in the eastern part. My uncle used to be reseller for International Tractors years ago, a lot of pullers where customers. Hopefully you helped him out on the shipping invoice, since duty is 12% and Tax is 19%.

Is in the previous assumption more fuel needed or is the "Head" more efficient with fuel (relatively)?

 

SKIP, what cam and head do you think would work on a CrossFire injection vette? I have an 82 CF also and I have a ported out CF manifold I bought a few years ago that I want to install with high flow TBs. With long tight runners the CF must have some good velocity with the right set-up.

 

Great thread.


Some forum mebmbers= embarrassed at their behavior.


geesh, anyway... This thread was very informative and helpful in how I am going to build my next (cheap) replacement engine for our few AutoX and track days.


btw... They are obviously "value priced" (get what you pay for) heads. I don't know why certain members were piling on this Skip guy. Gesh, If you want kick *** heads and willing to pay for them, go to the usual domestic builders. But, if you want an alternative in value and are willing to roll the bones, this is a decent option too!

 

Hey hugie82
If you are not familiar with them Im surprised. Google cross fire injection vault. These guys really know their stuff. So much so that a lot of it leaves me scratching my head. The forum has recently been revamped and it lost a lot of info but most of the members are still there and can answer any questions you have.
Some examples of what they have done.
bore out throttle bodies
refalsh chips
change computers
My favorite-make a custom plate to mount the throttle bodies on a SY1 intake.
And the list goes on. Give them a shot.

 

Monte, I have been to the CF forum many times. I was trying to see if Skip had a suggestion for a high torque/low RPM head. Monte, what is this SY1 manifold. I have heard of it but never seen it. Does it look like the X-RAM and does it fit under the hood???

 

If you google SY-1 intake you should be able to find out what it is. i can give you a somewhat intelligent description.
The Sy1 was developed for Edelbrock by Smokey yunick. It is a single 4 barrel cross ram manifold developed for nascar or trans am racers. It is a fairly rare piece but they are going for pretty cheap on ebay if the seller doesn't have a shy high reserve. The economy is killing everything. It is suppose to be a high RPM manifold. 3500 to 7-8000 rpm, but there are reports that it is a killer mid range manifold with decent low RPM manners. I am going to try it on my 70 camaro when I finally get the engine together. i will be running that ZZ4 roller cam and a 650 cfm carb to try and keep the signal up with that big plenum.
The CFI forum guys have made adapter plates for the manifold. It is a two piece manifold with a lid. They replace the lid with the custom piece. I hear it is a close call on clearance. By looking at my 82 vette I doubt it will fit without surgery on the hood. I'll cross that bridge when I get to it.