302 head machine work

jonmark1985 · 10-27-2007, 07:24 PM

I plan to rebuild the motor in my thunderbird sometime soon, so I've come to the conclusion that i will have to get the heads and block milled and decked. I ordered a set of guideplates and rocker arm studs from Powerhouse out of Bakersfeild Califonia. Ran $50 for all of it including shipping.

I've decided to practice on an old E7TE-PA head. I bolted a peice of aluminum to each side of the head and then set the head down (rocker arm boss facing down) flat on a BridgePort milling machine. After clapming the head down i machined the aluminum blocks. Then i flipped the head over and reclamped it. Then i removed .147" (the thickness of the guideplates) from the rocker arm bosses.

Monday I should have some more time in the machine shop. I need to drill out the old holes for the rocker arms and tap the holes for the 7/16-14 studs.

I hope to post more pics!

jonmark1985 · 10-30-2007, 05:10 PM

I bolted aluminuim brackets to the sides of the heads. Then layed the head on the millling machine's work down flat on the rocker arm bosses. Then i made the plates true to the rocker arm bosses. I then flipped the head over and cut the rocker arm bosses down .140"
Then i drilled out the old rocker arm bolts holes with a "U" drill and tapped them to 7/16-14.
It looks like the studs are huge, so tall, but i think they are going to clear factory valve covers, boy do i hope so

jonmark1985 · 01-15-2008, 01:52 PM

Sorry for that late post, but I feel that this needs some conclusion.

I'm almost certain a factory valve cover will fit.

flethed · 06-07-2008, 05:05 PM

Thanks for the info, I just found out the hard way they needed milling down. Anyway now that the heads are on i might as well match port the intake any helpfull hints on this prosess?

jonmark1985 · 07-10-2008, 04:48 PM

yeah, i wish i would have gotten on here sooner though,

Get some machinist's dye, and mark around the outside of the ports. Then use the intake gasket that you care to match to and a scribe and trace the outline of the intake port to the head. Use a pneumatic die grinder to remove any material that could be seen as an obstruction. You'll want to go back into the port about a half inch. The goal is not to remove as much material as possible but rather to make a smooth transition between the intake manifold and the head.

For just about any factory 302/351w head (excluding the 302 boss) I'd recommend gasket matching to Fel-Pro's #1250 intake gasket.