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View Full Version : Head Questions-need help fast!



SCaddict
11-27-2004, 01:55 PM
I took my heads to a shop to get them ported and the guy has never worked on a set of SC heads before. He has built tons of race engines which I have seen and heard, so I am not worried about his work. I need to know some of the things to do and not to do. David Dalke has given some of the do's I need to know if there is any don'ts. The guy wanted me to gather information and get it back to him right away. He pointed out many of the problems David D. pointed out, I just want to make sure it is being done all right. He said some of the work may lower the compression, but could be brought back up when I mill the heads. Any thoughts?

thebigslide
11-27-2004, 04:06 PM
I notice you don't have adjustable rocker arms. When the heads are milled to raise the compression back up, the pushrods will become too long and your valvetrain geometery may be out of sorts.

You'll need to get new pushrods and rockers and studs, or possibly consider welding the combustion chambers to shrink them instead of milling the heads more than is needed to surface them.

I'm a fan of coated valves, pistons and combustion chambers. Using a ceramic coating you can normally manage an extra 5psi of boost or 1.5 compression for the same octane fuel. Imaging running 9.5:1 on pump gas with 12psi of boost!

tim
11-27-2004, 04:20 PM
Dont make the exhaust ports bigger.

Dahoopd
11-27-2004, 04:59 PM
I second Tims statement. I had the exhaust ports opened up and its a slug. The car pulled harder with blown headgaskets.

tim
11-27-2004, 05:25 PM
I had my heads donr by a local shop. I didnt know much about S.C. heads except one thing. Dont make the exhaust ports bigger. I had the intake ports on the intake manifolds and heads matched to the gasket. I had bigger valves installed. The exhaust ports were cleaned up a tad and that was it. They are not as good as they could be but when I get the money i will take them to steg to have the exhaust ports redone. Heads are critical and easy to ruin. I would only let someone that is an S.C. expert rework them. Randy Baker is also a pro if you could get him to do them, problem is he is really busy.

SCaddict
11-27-2004, 11:57 PM
I am not looking to go mad on the heads at this point. I will only take off as much on the heads as necessary to make sure they are true. I don't want to have to get anymore parts right now. I just want a good port job, gain some extra power and maintain stock cam and spring etc... Is there any issues with this?

tim
11-28-2004, 01:09 AM
Things to do, port match intake. Good valve job. True head less is more. Take off as little as possible to get the heads straight. If you are trying to get by with good work and not spend a lot of money that is what I would do. Dont let anybody experiment on your heads. If they dont know S.C.s porting is not a great idea. They can domore harm than good.

SCaddict
11-29-2004, 09:06 PM
The guy was not going to touch the exhaust ports. I am going to bring him the intake for port matching and also the gaskets to match those as well. He is mostly going to consentrate on unshrouding the valves.