Rebuilt Model A engine

oldspert

oldspert

Senior Member
I picked up a Model A engine that has been rebuilt. Bored .080, crank counterweighted and turned .020 on rods and mains. Balanced with lightened flywheel and V8 clutch. All new valves and guides, adjustable lifters, new timing gear, and more. Just has been in a barn for many years, will have to be disassembled and cleaned up. Surface rust on everything that was exposed. Cam looks great and is a "B" grind. Should really make my 29 coupe a pleasure to drive.
Ed
 
Get a good gasket, and a high compression head. It make them run cooler (believe it or not). More pep too.
 
The valve springs can take a set with use but I doubt that sitting in a compressed condition will hurt them (the valves that have been open). If in doubt, check the spring rates or compare the free heights of the compressed springs with the others.
 
oldspert said:
I picked up a Model A engine that has been rebuilt. Bored .080, crank counterweighted and turned .020 on rods and mains. Balanced with lightened flywheel and V8 clutch. All new valves and guides, adjustable lifters, new timing gear, and more. Just has been in a barn for many years, will have to be disassembled and cleaned up. Surface rust on everything that was exposed. Cam looks great and is a "B" grind. Should really make my 29 coupe a pleasure to drive.
Ed
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How long was it sitting?
 
There has been a battle raging ever since semi automatic handguns came out in the very early 1900’s: Does keeping the cartridge magazine fully loaded when the gun is not in regular use cause any alteration in the spring (weaken it, cause it to take a set, etc.). It’s been 120 years and the debate is still going. In my (humble) opinion, I would side with Smoked Tires. The cost of the springs is minimal and if you are taking the motor apart anyway I feel that it is just cheap insurance. Kudos on a good motor with a weighted crank (I’m assuming that you got a good deal on it and since the crank alone can be over $1,500 I’d say anything less than 3k is a good deal). Since you have been a member here since 2012 I’m going to assume that you know what you are doing and don’t need a bunch of coaching from the peanut gallery. I have a question (and it’s for my own information), you say that it has a “B” grind. How do you know? Can you tell by looking or is that just what you were told? I have 2 cams that I was told were B grind, and another that is a “high lift cam”. I can’t tell by looking myself and I tend to question what a seller tells me (half the time they are dishonest, half the time they are exaggerating, half the time they are ignorant, and half the time they are honest and know what they are talking about). I am debating as to wether I want to use any of these cams, I want to really know what I am using.
 
J Franklin said:
What purpose would different valve springs serve?
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Could help avoid valve float if some springs have been sitting compressed while others without compression. Could always check each springs compression rate if the gage is available. For me, it's just cheap insurance.

For my full roller engines, I was always told to replace springs to assure the valves are following the cam accurately.
 
Jeepguy, The only reason I say it has a "B" grind cam is because the paperwork I got with the engine said the cam was a "B" grind. How much difference it makes is any bodies guess. It has many more items that are documented also.
 
According to a post on Model-A-Ford.org the intake lobe lift on the A cam is .302” vs the B at .334”. Could a micrometer be used? Of course this doesn’t account for ramp profile, but it might rule out having another A cam. Does this make sense?
 
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