I am restoring a 1950 f-1 pickup and am keeping it all stock but would like to make some extra HP from modifying the engine internals.
I have the stock running 8ba engine out of the truck, it has one bad exhaust seat and cylenders have some ridge. it has been rebuilt before as the pistons have .030 stamped in them. I also have a merc 4" crank for it out of another junkyard flathead I tore down.
I also have a, standard bore, standard crank merc 4" EAC engine that is in nice running shape.
My question is:
will I be happy with the stock merc engine performance or should I rebuild, stroke with the merc crank, and cam up the ford engine. Also would a .060 overbore scare any of you?
I am torn between using the stock low mileage engine or building one myself.
1923 model t, 1930 model a coupe, 1930 model a hotrod, 1948 f1 restoration project, 1952 f1, 1952 4x4 f1, 1956 victoria,1959 land rover, 1968 bronco restoration project, 1974 bronco rock buggy, 1979 f150, 1979 f350 4x4
First thing I would do is to tear them down, get them Hot Tanked and Crack Checked, If your lucky both blocks will be good and then the question can be asked again. These ol Flatmotors have lots of cracks, some repairable, some terminal.
1948 Ford F1 Panel
1952 Ford F2x2 (Non-Stock Flat 6)
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You have the same situation I do. Well, almost - my 8BA has a cracked cylinder, but I've got a stock bore block sitting and waiting. In order to keep driving I installed my merc engine. When I get the backup engine running again, the merc comes out for reboring out to 3 5/16" which will give me 276 cid with room for another rebuild some day.
Flatheads can generally always be bored .125 over - that's right, 1/8" overbore. Some will go to 3 3/8" and a few will make 3 7/16". So +.030 is just getting started. You've got several more rebuilds there. Just remember if you use the spare merc crank you've got to use merc pistons with it.
I'm happy running the merc stock engine, but you gotta chase the HP dream.... right? I think you'll be happy with the stock merc if you go ahead and buy the headers, dual pipes and improved intake stuff (dual carbs or 4bbl 390 cfm) to allow it to breathe to the max. You'll use that stuff when you build your hot flathead anyway.
The difference between an 8BA or an 8RT beside what's cast in the head, I believe is only that one has hardened valve seats installed from the factory, or they both may have it. I know that an EAB is a late car motor and does not have hardened seats in it....but other than that, find the heads with 8RT cast in them and voila, truck motor for all who look at it...
I believe the engine in my 52 F3 to be an 8RT, but neither head has that mark. In the place where the mark would normally be, there is nothing. The pan does have a large round clean-out or access panel, which I believe was present only on truck engines.
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All intakes 48-53 are marked 8BA/8RT. As far as I know the things that make an 8RT are bolt-on accessories. As mentioned: oil pans, water pumps, fans, heads, location of oil filter, etc and maybe the cam (probably a few other minor things that escape my memory at the moment), but head displacement is nearly the same as the 8BA.
I figure if you have a late model flathead V8 your '48-'52 truck it is period correct. Fords had so much variation in casting marks that anything more is wishful thinking.
........plus everything bolts to everything else. My '48 pickup has a '51 merc flatty with ford intake and earlier carb, truck oil pan and waterpumps, etc, etc. Imagine someone 50 years from now assuming it came from the factory that way..............
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