Flathead Ford vs Mercury

I understand that with a 4" stroke [or +] the EBA heads will produce a higher compression ration than the 8cm/ECA Merc heads. Newc
 
jimTN said:
All the internals from the 49-53 engines will fit in the early 59AB bocks. While the late engines had a different dist. some folks do use the late camshaft, front plate and dist. Another advantage of the early block in a 40 or earlier frame is that the stabalizer rods will attach to the block.
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So you're saying an engine rebuild kit for an 8BA will work in a 59AB?
 
The crankshaft, rods, rod bearings, valves, valve keepers, and valve guides from an 8BA style engine will swap into an earlier engine. This provides the benefit of easier assembly while keeping the exterior looking stock. If you use a 4" stroke Mercury crankshaft you gain bolt in performance with a stock look. I plan to do exactly that myself one day. I finally have almost all the parts to assemble a bone stock looking 1938 engine with 262 cubic inches (+.040 1939 Mercury block with 4" crank, 1938 24 stud heads, etc).
 
Some folks want to keep the front distributor and the old style cam & gears will work for that on a 59 series. Main bearings follow the block. 59 blocks use the 59 main bearings but a 255 crank will fit them. Folks used to get Gary to sleeve the one piece guides with bronze for stainless valves. If the stainless valves are plated on the stems then a bronze guide liner isn't needed. Stainless likes to gall on a cast iron guides in some cases. Chevy valves need a bit of work to fit a flathead and there are plenty of flathead type valves that can be used depending on application. Larger valves don't help much on a flathead.

Some Johnson adjustables are solid cast iron and the late hollow ones are replicas of those that sometimes won't hold adjustment. Folks build a lot of stuff out of a catalog and what hear say is telling them. The L-100 cam is a proven grind that should be good to go for mild performance. A person can get good performance from a set of EAB heads properly milled for better compression but they aren't purty like the Offys.

Mercury heads of the 8BA family were made to reduce compression to mach the basic ratio of the smaller 239 engine. They have larger clearance volumes than 8BA and EAB heads. The EAB heads have the lowest factory compression and lower the compression on a 255 pretty well. "Mercury" doesn't always mean better. It depends on which Mercury component is involved. Merc cams and cranks improved things but the heads not so much.
 
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rotorwrench said:
Some folks want to keep the front distributor and the old style cam & gears will work for that on a 59 series. Main bearings follow the block. 59 blocks use the 59 main bearings but a 255 crank will fit them. Folks used to get Gary to sleeve the one piece guides with bronze for stainless valves. If the stainless valves are plated on the stems then a bronze guide liner isn't needed. Stainless likes to gall on a cast iron guides in some cases. Chevy valves need a bit of work to fit a flathead and there are plenty of flathead type valves that can be used depending on application. Larger valves don't help much on a flathead.

Some Johnson adjustables are solid cast iron and the late hollow ones are replicas of those that sometimes won't hold adjustment. Folks build a lot of stuff out of a catalog and what hearsay is telling them. The L-100 cam is a proven grind that should be good to go for mild performance. A person can get good performance from a set of EAB heads properly milled for better compression but they aren't purty like the Offys.
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Thanks for the reply, I ended up starting a new thread for this question
 
rotorwrench said:
Some folks want to keep the front distributor and the old style cam & gears will work for that on a 59 series. Main bearings follow the block. 59 blocks use the 59 main bearings but a 255 crank will fit them. Folks used to get Gary to sleeve the one piece guides with bronze for stainless valves. If the stainless valves are plated on the stems then a bronze guide liner isn't needed. Stainless likes to gall on a cast iron guides in some cases. Chevy valves need a bit of work to fit a flathead and there are plenty of flathead type valves that can be used depending on application. Larger valves don't help much on a flathead.

Some Johnson adjustables are solid cast iron and the late hollow ones are replicas of those that sometimes won't hold adjustment. Folks build a lot of stuff out of a catalog and what hear say is telling them. The L-100 cam is a proven grind that should be good to go for mild performance. A person can get good performance from a set of EAB heads properly milled for better compression but they aren't purty like the Offys.

Mercury heads of the 8BA family were made to reduce compression to mach the basic ratio of the smaller 239 engine. They have larger clearance volumes than 8BA and EAB heads. The EAB heads have the lowest factory compression and lower the compression on a 255 pretty well. "Mercury" doesn't always mean better. It depends on which Mercury component is involved. Merc cams and cranks improved things but the heads not so much.
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Are you sure this is what you meant to say here? Did you mean "EAC" heads? Also, I thought that the "8RT" heads were the lowest compression of the 8BA series, though I have never gone to the trouble of measuring them.
 
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