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mlr1026
12-04-2005, 01:39 PM
Hi all, I decided to go with a fuel injection unit for my firebird but I ran into a problem. The engine is your typical sbc out of an 88 vette so why is it that the holley stealth ram pn#91505201 doesn't sit right? I called them up & they said to use felpro gasket #1206 which are .060 thick but I still seem to have a gap. Now, I forgot my micrometer at work so I really can't give you guys any numbers. but as you can see from the pics. there is a raised area on the heads. Does anybody know why this is here & more importantly how do I resolve this issue without removing the heads having them milled. I thought the heads were your run of the mill 58 cc chambers now I'm worried. What are they?

camcojb
12-04-2005, 02:01 PM
My Hogans sheetmetal manifold was the same way on LT1 heads. I had to machine the intake to clear. Pretty simple but I didn't expect it.

Jody

mlr1026
12-04-2005, 02:20 PM
Won't that make the area around the injector very thin?

camcojb
12-04-2005, 02:50 PM
Won't that make the area around the injector very thin?

very possible, that manifold may not work on those heads. On my Hogan manifold it was fine but they locate the injectors in a different spot.

I just went out to my shop and looked at the stealth ram I have out there; it does not have that injector boss out like that, it is flat across the top of the port. I wonder if that's an older designed manifold or why it is that way.

Jody

Nova-Mann
12-04-2005, 07:12 PM
I have an '87 Vette, so I went out in the garage to look. The heads have the same ridge on them. I couldn't tell you why they machined it that way, but I see how it causes problems.

Nova-Mann
12-04-2005, 07:15 PM
Another thought. There are two stealth rams; one for old style heads and one for Vortec heads. The ports are different.

nancejd
12-04-2005, 07:15 PM
Do your heads have vertical intake manifold bolt holes? I think GM chnaged how the intake mounted to the heads around '88.

Nova-Mann
12-04-2005, 07:19 PM
Check with Andrewb70. He works at Holley and can help you with it.

andrewb70
12-05-2005, 06:13 AM
Check with Andrewb70. He works at Holley and can help you with it.

I actually no longer work for Holley, but I will do what I can to help.

Mario, I sent you a PM, but now that I am reading this post I am know what the problem is. The manifold that you have there must be fairly old. I can tell by the tooling points. Like Jody said, not all manifolds work on all heads without modifications. It is actually fairly common that the manifold will need to be trimmed in exactly the area that your showing in the pictures. If you are comfortable you can trim the area yourself by hand. If not, then you can have a local machine shop mill the area. Make sure that you take off as little as you have to. I would also use a 1205 FelPro gasket. The 1206 is HUGE and there is no reason to use it with the heads that you are using.

Andrew

mlr1026
12-05-2005, 06:50 AM
Thanks For The Advise Guys

Kenova
12-05-2005, 08:09 AM
The aluminum heads I used on my 400 sb appear to be the same as yours. I'm using an older Wiend Xcellerator single plane on it. When I went to drop it on, I experienced the same problem. I spent a half hour or so trimming the sides of the manifold down with a file. I think you should be able to do the same without causing any problems with your injector bosses.
Ken