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Discussion Starter #1
Hi all,

I picked up a set of D0VE-A heads for my '67 Mercury Commuter Wagon (has a '78 460 in it presently) and have decided to do some port work on them. The car will be a driver with nothing more than an RV build. Mild cam, cast iron exhaust manifolds, and a performer intake with a Holley 750.

My focus is primarily on the exhaust side as I'm sure that will be the bottleneck. The intake side will get very minimal work blending a couple of transitions. Finally, the combustion chamber will get a little work as well as the seats were previously replaced and look like they were set a little low, so I want to blend the combustion chamber into the seat.

My goal isn't to maximize horsepower out of the head, but to improve performance and mileage with my specific set up.

I will post additional pictures as I go in case anyone is interested. I've included a couple of before pictures.

Thanks,
Paul
 

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Since you're not worried about chamber CCs since you are dropping about 20 off, the best thing in the chambers themselves is to get rid of the sharp edges from the machining around the valves. "Unshroud" them. The ports, on the intake side, just remove the shape edges and gasket match.
Exh side, the smog hump and top part of the outlet is where you need the most work.
I'd also have bronze guides one now too.
 

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LOL! 20 CCs. I think it might be a bit shy of that. This is for a 4300 lb wagon with a highway gear and an RV cam, so no, getting 10.5:1 compression really wasn't a concern. The heads were shaved .010 previously, and the pistons are stock '78 so I should hit about 9.0-9.5:1 which is what I was looking to get. Aside from that, you pretty much described everything that I already did.

Removing the sharp edges as well as polishing the combustion chambers is exactly what I did ... to help reduce concerns of pre-ignition. And, then I did unshroud them. That was where I blended the chamber into the seat. Right at the seat I had to leave a bit of ridge to avoid hitting the seat or creating an shallow area right at the valve that would disrupt flow.

On the intake port I blended the hard corner just inside the port past the intake. I also opened the port to allow the intake to flow into the port without any hard edges disrupting the flow and then blended it in about 2.5". At the valve side of the port I cleaned up the casting blending in about the first 1.5"-2".

The smog hump is long gone and blended into the rest of the port prior to polishing. My goal wasn't to enlarge the port as it was to smooth and blend. The bottom of the exhaust port was blended at the turns and polished, but otherwise left alone. The top of the port received the bulk of the work. The port opening was left basically as cast as far as size goes. One thing I did do was eliminate shrouding of the valve in the port where the seats. When the seats were installed, they left a ridge roughly 1/32" all the way around. This was blended into the seat.

Brass sleeves were already installed, so no worries there.
 

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You're probably going to get about 10.2 Comp ratio. 76 vice 96ccs and probably -2ccs with the milling. They lowered the comp with the heads those years. Good towmobile. I used the same engine setup in a 72 2dr LTD with a frame Class III hitch pulling a 18' trailer and 3300# car. worked good for me.
 
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