The Ford Barn - View Single Post - Oversize OD main bearings for 37 21 stud block

Yoyodyne · 09-10-2020, 10:37 AM

L-head - at .015 over you'd have to move the bore centers way too far up into the block to be useful afterward.

Brian, how much narrower are the later center mains? Milling that to size seems like the easy part of the job.

Pete - Sounds like you have made and run aluminum bearings? How has that worked out long term? What alloy would you recommend?
I made some Durabar bearings for a rotary engine running 70 lbs boost on alcohol because the OE bearings were getting destroyed, but I never got to see the results.

Putting a later crank in the 36-37 block opens up a lot of possibilities for a hot rod 21 stud. I think I could put a 38-42 crank in and use 21A rods with 38-42 rod bearings, this would allow use of new production bearings and make them easier to find and buy. I could put a Merc crank in for a stroker or even a 4-1/8 stroke - is the crank compartment of the early engine the same as a 59A as far as fitting a stroker?
With flat top .100 over pistons I have here I could offset grind a 59A crank to 3.875 stroke and turn about .020 off the top of the pistons to get the deck height I want without decking the block much and get a few extra cubic inches on the cheap.

Please forgive some of the basic questions, I'm only really familiar with 35-37 engines, don't have much else to look at/measure without traveling.

09-10-2020, 10:37 AM	#28
Yoyodyne Senior Member Join Date: Nov 2010 Location: Lancaster PA Posts: 535	Re: Oversize OD main bearings for 37 21 stud block L-head - at .015 over you'd have to move the bore centers way too far up into the block to be useful afterward. Brian, how much narrower are the later center mains? Milling that to size seems like the easy part of the job. Pete - Sounds like you have made and run aluminum bearings? How has that worked out long term? What alloy would you recommend? I made some Durabar bearings for a rotary engine running 70 lbs boost on alcohol because the OE bearings were getting destroyed, but I never got to see the results. Putting a later crank in the 36-37 block opens up a lot of possibilities for a hot rod 21 stud. I think I could put a 38-42 crank in and use 21A rods with 38-42 rod bearings, this would allow use of new production bearings and make them easier to find and buy. I could put a Merc crank in for a stroker or even a 4-1/8 stroke - is the crank compartment of the early engine the same as a 59A as far as fitting a stroker? With flat top .100 over pistons I have here I could offset grind a 59A crank to 3.875 stroke and turn about .020 off the top of the pistons to get the deck height I want without decking the block much and get a few extra cubic inches on the cheap. Please forgive some of the basic questions, I'm only really familiar with 35-37 engines, don't have much else to look at/measure without traveling.