Edelbrock head porting

[Pentroof]

In my adventures of converting my 428 to EFI, I happened to become the owner of an extra set of used Ed heads from a guy that owed me money. I was going to throw them on evilBay, but have decided to use them as the mates to the new Victor intake, allowing me to perform all the porting and matching while the current motor is still in the car, keeping my downtime minimized. The best of both worlds.

I have the heads torn down and cleaned up and am happy to report they are almost new, based on the valves, guides and seats. I was a little worried, but it turns out the valve cover leaks and poor carb tuning made the heads look much worse than reality. A little brake clean, some Eagle One machined wheel cleaner and they look like brand new castings.

I am going to have a local shop put a new grind on the valves and seats but I am starting to think about porting. I am going to leave the port size alone and match the intake to it, but was wondering about experience with bowl cleanup and blending on these particular heads. Are there gains to be had, and are there pics available to demonstrate particular areas on these chambers that are of concern? I will be running a Comp 294S cam and stock Edel sized valves (CJ) with appropriate matched springs, to give you an idea of the dynamic constraints.

I thought about sending them out for full NC porting, but I don't know if that is beyond my needs. I'll probably end up in the 540 hp range.

Thanks for any input guys.

Jim

[cammerfe]

All the ebock heads I've ever looked at show very clear evidence of indifferent touch 'n' go-work in the runners. The basic cnc work only extends into the runners an inch or so and it's evident where the cutters stop. Blending of the cutter marks, and any evening out in the roof areas will bring dividends.

Remember that the ebock head isn't quite as good as the factory MR to begin with.

KS

[Barry_R]

There is a lot to be gained from a better valve job and bowl work.  The Edelbrock valve job is rudimentarty at best.

[Qikbbstang]

Designate left and right heads, scribe each chamber through the cylinder block with the cyl bore, if it's a later 427 be sure to catch the valve reliefs in the cyl walls,  then open up the chambers to your bores and pay attention to the walls in the chambers that are right up beside the In & Ex valves besides relieving them you can do a slight undercut in the wall by the seats. This undercut is said to allow the flow to start earlier and gain momentum at low valve lift.  If you note in the stock ED heads the valves are partially blinded by the chamber walls until the valves are seriously open.  Big valve swaps just make the problem worse.  Someone here just stated that Ed Heads are not true M/Rs.  I have a feeling they are a bit narrow on the intakes -  do some searching for different Int gaskets and base your work from there. The Ed Heads obviously have a dam good designs in the ports as delivered, they were designed decades after FORD and with Eds offices full of port gurus.  Keep in mind you want to enlarge but still maintain the stock profiles  -- not being creative and hogging the hell out of them here or there. Obviously the valve guide support areas are a major impediment that you can spend plenty of time on.

Remember the Ed Heads were made to match up with 390 bores the bigger the bore the more need for relief. 

JMHO