garandfan

Well I think I decided to go with a ZZ4 motor. I have some questions regarding headers. I want to retain my stock sidepipes. Have any of you put headers on a ZZ4 motor with the "D" shaped ports? if so have any of you retained your stock 69 style side pipes?

I need to figure out who makes a shorter header for the heads used on the ZZ4's. I don't think mid length or long tubes will work with the side pipes.

Any help would be appreciated.

Thanks again.

Frank

Shark Racer

Hooker sells sidemount headers.

BSeery posted in another thread that the header port style will not make a big difference in performance according to GM.

-Steve

Smokehouse69

Do you have stock exhaust manifolds on your car? If so then you can put them on a ZZ4, if you want headers then connecting them to stock side pipes it is a little harder, unless you use shorty headers. Either shorty headers or you'll have to come up with some creative "S" curves from the collectors to where the sidepipes come out from under the car.
Don't worry too much about the "raised D port" exhaust ports, they are only about .25-.30 higher than stock ports and really not shaped all that differently than stock heads. The difference in height on the ports doesn't really affect how the exhaust hooks up since you can pretty easily find that amount of play in the up and down movement of the stock exhaust.

hauk

I bought a set of "D" port headers from hedman for my 73,I have had them about 6 months and I like them,They were a bit hard to install but worth the trouble :)

theandies

Here are the Headman Headers with "D" shaped ports for the ZZ4. Since you have side exhaust then these will not work unless you go back to undercar exhaust. Everyone is probably correct when they talk about the performance loss over oval ports but if you were a serious racer and were looking for every advantage then port matching is one thing that can be done to squeeze out that extra 1 to 2 HP...which may make the difference between beating that Rustang or loosing to it.:D

BSeery

In the GM manual for the ZZ4 they talk about the D ports. They say that testing with both D port headers and standard headers produced the same results. You are actually connecting to a larger area so there is no flow restriction.

As far as some really good shorty headers - http://www.sandersonheaders.com - they are the best quality for shorties.
http://www.sandersonheaders.com/page...tnum/cc1ho.htm


[Modified by BSeery, 7:39 AM 9/26/2003]

Sigforty

I just used my Dynomax ceramic coated headers. They fit right on and with a nice set of percy's aluminum gaskets I have not had any problems.

theandies

Brian,
Your engine came with a manual? Mine didn't. How many pages is it? If it's not too long think you could send me a copy?
John