Flathead Piston and Ring Questions...

I have a piston and ring question also, (I havnt quite figured out how to start a new post)I am fixin to rebuild a 41 3-1/16 bore v-8 The pistons in it are the 3 ring originals I want to go back with a set of aluminum pistons( NEW OLD STOCK ) will the aluminum pistons and factory cast iron rings be compatible with the thin cylinder liners?
or will I have to use cast iron replacement sleeves or will I have to bore the block and run the std. late 239 pistons?
Thanks !
Fordestes
 
Ol' Ron said:
To each his own, The Egge Piston is cast fron a hi Silicone Aluminum which allows a tighter fit. I've been fitting then at .002" and so far nobody has had any trouble. I have Ross pistons in several street engines set at .004 and they don't make any noise when warm.
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Thanks again Ron. Looks like I will be going with cast pistons with as high a silicon content as possiblewith the modern style rings. I like the idea of building to a tighter tolerance and having less engine noise.

I have also been offered the following tips from a fellow Flathead builder and would value your input:

Make absolutely certain that a "Block-Plate" is used on the final hone. These blocks "move" around substantially at the head bolt holes when finish-honing AND it's worth some "free" horsepower.

We also now have a head-pinning fixture to keep the head gasket's from "moving" around! We made this possible most recently on one build!

Have the shop remove all 4 pressed plugs on the crank throws and DRILL & TAP for 3/8" pipe threads! If you (or the shop) don't remove those existing core plugs you will NEVER have a clean crank for the new build!

Are these something with which you have experience?

Thanks again, Jay
 
Also do final valve seats with the plate in there...
Anyone know the thickness of the iron plate that is the basis of the Speedway pressure testing kit?? Seems like a useful tool just for testing block, and now I'm wondering if it contains enough iron to be a good block plate.
Cylinders pucker a bit where the fasteners are, hence the need for them to be round with fasteners in and tight.
 
Bruce Lancaster said:
Also do final valve seats with the plate in there...
Anyone know the thickness of the iron plate that is the basis of the Speedway pressure testing kit?? Seems like a useful tool just for testing block, and now I'm wondering if it contains enough iron to be a good block plate.
Cylinders pucker a bit where the fasteners are, hence the need for them to be round with fasteners in and tight.
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I don't know the thickness of the speedway plate or the material it's made of. I would call them and ask questions before buying.
They also must have a rubber gasket, if it is molded on to the plate you couldn't torque it down enough to use as a torque plate. if it is a separate gasket the plate would work if it is thick enough to take the torque. maye someone on here has one??

http://www.speedwaymotors.com/ProductSummary.aspx?free_text|9/10/2010%202:31:20%20PM=ford+flathead+pressure+tester&deptId=0

Offenhauser Flathead Ford Pressure Tester Kit
Price: $254.99


Flathead Ford V8 Pressure Tester Kit
Price: $249.99
 
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Ol' Ron said:
This is a good builder, In my opinion, Keep him.
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Thanks Ron. As this is my first experience with a Flathead your input makes me feel better. I may call upon you and Bruce and the others who have been so generous with their knowledge, once again before I have completed this project. J
 
jdl said:
I don't know the thickness of the speedway plate or the material it's made of. I would call them and ask questions before buying.
They also must have a rubber gasket, if it is molded on to the plate you couldn't torque it down enough to use as a torque plate. if it is a separate gasket the plate would work if it is thick enough to take the torque. maye someone on here has one??

http://www.speedwaymotors.com/ProductSummary.aspx?free_text|9/10/2010%202:31:20%20PM=ford+flathead+pressure+tester&deptId=0

Offenhauser Flathead Ford Pressure Tester Kit
Price: $254.99


Flathead Ford V8 Pressure Tester Kit
Price: $249.99
Click to expand...

The gasket is molded to the plate on the one I got from Speedway.
 
Fordestes said:
I have a piston and ring question also, (I havnt quite figured out how to start a new post)I am fixin to rebuild a 41 3-1/16 bore v-8 The pistons in it are the 3 ring originals I want to go back with a set of aluminum pistons( NEW OLD STOCK ) will the aluminum pistons and factory cast iron rings be compatible with the thin cylinder liners?
or will I have to use cast iron replacement sleeves or will I have to bore the block and run the std. late 239 pistons?
Thanks !
Fordestes
Click to expand...
You can remove the steel liners and use a set of .083 over pistons. All you need to do is have the cylinders honed properly. These pistons used to be readily available. Don't know about now. Try Egge.
 
Jay Ess that is a good queston. I have ben thinking along the same lines. I do have a eaton blower and a Brother that is a master pattern maker. We looked at making a intake to adapt this blower to a flathead.I have a lathe and milling machine and a smelter to melt the aluminum. I JUST CAN'T bring myself to run one of them that hard. Ol Ron hase the right system fromthe way I think. I don't know it is like the Old LADY THAT KISSED The cow. Ti just a matter of tast. Lyle Love Da Barn
 
I got one of the Speedway pressure test kits and have used it once. Can't remember now, but I think I only used 40 psi. I followed 'barners tips and used a spray bottle with WD40. Initially found leaks around the water pump covers and had to do some bolt substitutions to get them clamped down. Seeing and hearing those leaks trained me as to what to look for around the valve seats. I had no bubbling or fizzing around the seats or cylinders so I think the thing passed. I'm happy with my purchase and plan on asking for a $40 per test donation from fellow flatheaders to help pay for the set up. Better yet, every local EFV-8 club chapter should buy a set for the members to use.
 
36tbird said:
I got one of the Speedway pressure test kits and have used it once. Can't remember now, but I think I only used 40 psi. I followed 'barners tips and used a spray bottle with WD40. Initially found leaks around the water pump covers and had to do some bolt substitutions to get them clamped down. Seeing and hearing those leaks trained me as to what to look for around the valve seats. I had no bubbling or fizzing around the seats or cylinders so I think the thing passed. I'm happy with my purchase and plan on asking for a $40 per test donation from fellow flatheaders to help pay for the set up. Better yet, every local EFV-8 club chapter should buy a set for the members to use.
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Questions
Is the rubber gasket molded on to the plate or separate? what is the thickness of the metal? Thanks.
 
36tbird said:
I got one of the Speedway pressure test kits and have used it once. Can't remember now, but I think I only used 40 psi. I followed 'barners tips and used a spray bottle with WD40. Initially found leaks around the water pump covers and had to do some bolt substitutions to get them clamped down. Seeing and hearing those leaks trained me as to what to look for around the valve seats. I had no bubbling or fizzing around the seats or cylinders so I think the thing passed. I'm happy with my purchase and plan on asking for a $40 per test donation from fellow flatheaders to help pay for the set up. Better yet, every local EFV-8 club chapter should buy a set for the members to use.
Click to expand...

I tested three blocks with my Speedway kit and made sure it held 100 psi for at least 20 minutes. I did need to crank the torque down on the block and the pump plates.
 
"I tested three blocks with my Speedway kit and made sure it held 100 psi for at least 20 minutes."
Wow, how did you keep the block down on the bench?:D
Seriously, what radiator pressure cap do you plan on using? I have not been able to find any over 16 pounds.
 
38 coupe said:
One more thing to consider: in 1951 the piston pin was offset. This was done to even out piston side loads and to reduce piston noise. The quietest flatheads I have heard have the late rotating exhaust valves and the offset piston pin.

You don't want forged. They are overkill unless you are racing or using a blower. They require more wall clearance. Thus you spend more money to have a noisier engine that uses more oil.
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38 coupe. In your answer you said," One more thing to consider: in 1951 the piston pin was offset. This was done to even out piston side loads and to reduce piston noise." Does this mean that the wrist pin hole is NOT centered on the true vertical center line of the piston? And does this mean that the connecting rods and pistons must be be reassembled in the engine in the same cylinder they came out of? Do the 49 and 50 Ford and Merc engines align the pistons using the true centerline of the piston with NO offset? Thank you. JIM
 
Virtually all Ford pistons had offset pins, marked as such with a mark on the edge of the dome that points forward. There was no change in '51. The amount of offset is something like a 1/16th", but the number does not matter. The pins are actually not in the physical center. The connecting rods and pistons do not need to be in any particular hole. They can be mixed. If a prior builder has had the entire rotating assembly balanced, than it would be prudent to keep the rods with their pistons. Otherwise it does not matter, you can return them to different bores.
 
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