Technical Trying to rescue an 8BA Merc crank.

Just a quick question. We've got an 8BA Merc crank which we could rescue if anyone made 0.60 con rod bearings.
Is anything like this available? Perhaps a stroker kit?

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Not knowing what the prices are like over there, I can offer 2 suggestions : 1. locate an Industrial "Hard- Chrome" company or a crankshaft company & determine if they can either do the work to
,( or make a recommendation where to take the crank to have it done) weld build-up the journals & re-grind to "standard"(this will probably be EXPENSIVE!, so check with your doctor as to the condition of your heart before you ask the price!!) / 2. Check with SCAT as to what it would cost for a new crank(I would recommend buying a complete assembly, as it would come already balanced, & would probably, even with shipping, be cheaper than #1.) Hope that this helps.

 

I had an off topic crankshaft with a bad journal repaired by turning in the lathe to clean it up, then nickel plating and grinding to stock size. I was told the nickel was plenty hard enough.

It has held up fine.

 

Over thinking here! Just cut some more off of the throws and use 91A 0r 21A rods from 39-up 221 engines.
These were used on MOST racing flatheads, usually with offset ginds for a 1/8" stroke increase, but you will need to stick with stock 255 Merc stroke because an offset grind starting that small will put you back into the no-such-bearing jungle.

 

Total combination will be: Stock Merc '49-53 crank but with Ford 221 size throws, prewar 221 floater bearings, regular Merc 1949 main bearings.
After 1949 that is the basic combination for most hot flatheads.

 

How about that 4-1/8" offset ground crank that is .060 low in the hole? Perfect for a blower motor with lots of boost.

 

1/8 stroker use with 4" crank and 221 rods requires a pretty big journal, can't be done with an original crank that has been ground a lot...hard to visualize but you can only get a stroke increase of 1/2 what you grind away. I think this crank is going to be good for only stock 4" stroke, but at least it's still in business with 221 rods!

 

Up to at least 1967 McQuay Norris would supply 0.060 conn rod bearings for a small charge over their .002, .003, .005, .010, .020, .030 & .040 bearings. You would buy the 2975CP 60C semi-finished bearings for $6.45 and for $1.50 each they would machine to .060. So if you could find the 60C bearings you could machine to the size you required. Probably impossible to find today and if found would certainly cost much more than $7.95 ea!
TRW made them in std, .010, .020, .030, .040 & .050, no mention of .060.

 

I would check with EGG Machine as a starting point.

 

Maybe keep an eye out on the auction site for some of those very undersize NOS bearings.

 

I have seen .060 bearings for Stude sixes on ebay. You could probably find some for flathead Ford if you looked around. On the other hand, my crank grinder only charges $59/journal for welding cranks, plus the charge for the grind which is normally around $100.

 

Your crank grinder can also tell you if the crank is cast in which case he may not want to weld it.

 

All flathead Ford cranks were cast. They didn't forge any of them.

 

Except for 32's! I have a forged one.

 

Exactly, including the ‘60’s.

 

According to the patent info, the cast cranks (a very radical thing in 1934, even improved power and top speed) were cast STEEL, not nodular iron or whatever. That seems clear, though it contradicts everything else in print! The casting process was fascinating and creatively solve a LOT of problems.

 

I bought some .050’s from Baxter Ford in Kansas about a year ago; maybe they have what you need? Flatheads Forever!