ratman

summit racing has edelbrock alum performer heads for bbc for 979pr. get a set put in good valves and springs sell the valves and springs that come on them on ebay. bbc stuff brings all the money on ebay. the car guys jump all over it and pay stupid money for used parts.

KAAMA

I would replace the GM "peanut port" oval port heads with a better flowing set of aftermarket heads as most everyone else has suggested here.

But just so that you know, the "peanut port" heads CAN be made to flow much better by installing larger intake/exhaust valves, and having the ports opened up for more volume. However, it takes a TON of porting to do this, and may not be worth the time/trouble/money to go this route vs going out and buy the better flowing aftermarket castings.

Several years ago the late John Lingenfelter did some "peanut port" mods with larger valves, porting, and they flowed real nice, and made decent power on a 496 or a 502 (I can't remember)---but that was back when there wasn't as many head options as there are today. I still would opt for a better flowing aftermarket casting, but for whatever reason you feel you must retain the "peanut port" heads you have now, then that is an option/route you have with them.

jeffswav

Thanks for all the input. I realize the best way to go would be the Edelbrock Marine 454-O at $739.50 each. I am just trying to keep the cost down. I have already spent a ton of money on this thing and the votec heads looked like a good deal if I could pick up a used set cheap and rebuild them. However it looks like it will cost about $300 to $400 just for the castings, then you have valves, seats, valve job, porting. I just want to make the right desision before I spend anymore money. My machine shop does have a set of mark IV large ovals I could rebuild, but I would only save a couple hundred going that way.
Thanks,
Jeff

jeffswav

Ratman
I looked in Summit Racing and I could not find any for that price. Is that some sort of special I am not seeing?
Thanks,
Jeff

Pat McPherson

Hey Jeff,
I think Rattman is talking about bare castings.

How much $$ do you have to spend?

You could bolt on a set of L-29s and gain some power; how much???
Maybe another 25-30HP for $800-900.

The Edelbrock Marine or World Products large oval heads will cost you $1600-1700. Plus you will need to replace the flat tops, more $$.
But then your engine would be capible of Big HP.

jeffswav

My small oval ports have allready been ported as far as they can go. I spent a lot of hours on them 2 years ago with a rorory tool. I took out all the defects in casting, polished the bowls, gasket matched with the intake. However not knowing any better at the time I went back with the stock valve size. How much more would bigger valves give me on the heads. For example 2.19 @ 1.88 vs 2.065 @ 1.725.
Thanks,
Jeff

Pat McPherson

Probably 20-30HP. Not really worth the time and $$.
If you cut the heads to install hardened seats for larger valves, the bowls will likely need to be ported again.

Hey Jeff,
How did you get to 8.5:1 with flat tops? Did you deck the block and mill the heads?

Also are you sure your intake won't seal against rectangular port heads? Some oval port intakes do...

PatriYacht

Inconel exhaust costs 35-50.00 ea. Good intakes 15-20.00 ea. Right there you have 500.00 in valves. Seats have to be reworked for the larger valves. Hope you don't need to replace any guides. Then you need to machine for screw in studs. The Edelbrocks are a good deal when you look at it this way. Also they have a 110cc chamber option which will bring your compression up without buying new pistons.

PatriYacht

Jegs has them for 709.99 ea with valves but without springs, retainers.

amer3

cp has them for 1500. just need springs 880 6155 rec Edelbrock i have flow chart on them. had my flow when i got them.i can email it to you.


http://www.cpperformance.com/detail.aspx?ID=4094