[tubman]

I had a 390 Holley on a 276" 8BA in my '36 3-window 20 years ago; it was a trouble-free setup, but not the best looking on a flathead. I like the old Mallory' dual points. I have tried both the Mallory and a converted GM unit with vacuum and centrifugal advance on my cars. I prefer the Mallory, mainly because of looks (again), but I couldn't detect any difference in performance; perhaps I didn't spend enough time setting up the proper curve on the converted GM, but the Mallory runs perfectly fine as far as I am concerned.

Now we get to cylinder heads. In the above-mentioned '36, I just bolted on a set of new Offenhauser finned aluminum heads. I was never really satisfied with the performance of that engine. When I started paying attention to these forums, I learned about how important combustion chamber dynamics are to a flathead. Specifically, you want minimal clearance (squish) between the top of the piston and the head. Ideal is between .045-.050". Since learning about this, I measure the head/piston clearance with aluminum foil balls, and if the existing clearance is too large, I have the heads milled to bring it down to the proper clearance. I then do some work on the heads with a die grinder to make sure the clearance is consistent over the entire surface. I have found this results in a much better running engine, than just throwing a set of aftermarket heads on it. Stock heads with the proper clearances are better than a set of fancy finned aluminum heads that are just thrown on the engine. I personally like Edmunds heads, as the spark plugs are relocated just enough so they they are not directly over the exhaust valves. This allows me to run extended tip plugs that also add to the efficiency of the engine.

I have a 255" '51 Merc in my current '51 club coupe with the aforementioned mods (and a 2G carb rather that a Holley 4 bbl) that would have run rings around the 276" engine in the old '36.

I also use the original head bolts with hardened washers I get from "GOSFAST" on here and torque the heads as many time as required (cold) to get to a consistent 45 ft/lbs. No leaks so far. I also have a technique I use to make sure the heads move around as little as possible after they have been installed on the block. I can find the the thread if you would like to see it. I also use composite gaskets, as copper gaskets can cause electrolytic corrosion when used with aluminum heads (plus, they are usually more expensive).