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3.90 ring/pinion

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X2 on Steve.

Mike, I'm surprised to hear that. I figured the 3.90 would be the choice of the racing crowd.

I'm torn as it will cost me just as much to fab up the 1500/210 5speed swap as it will to get the gears in (total). I'd like both but funds are tight. I guess I might as well sacrifice the TR and have me Midget done up proper.
 
Hey Mike, if my old set and my new 3.55 both just have the <.> on them, I can just use the same shims/spacer and put the new set in, right?
 
2091351 said:
Fred, given your in Tulsa and know that just East of your location are some super roads for a BE, I would try to acquire two (2) 3.9's and use them up! :thumbsup:

Your 1275+ will be able to rip and tear with 3rd & 4th in the hills and the OD 5th will give you great Freeway (Tollway in OK) RPMS. :winner1:

YMMV

Steve
Click to expand...

Steve,

Great idea, I think a trip over to Eureka Springs is in order once the little car is back on the road. Probably next spring.

Fred
 
The 3.55's were solely a 1500 racing item. The 1500 cranks are so heavy and the block fairly flexible, that holding the rpm's down in the 6500-7500 range really extended the reliability. This was after lightening the cranks by quite a bit. The fastest 1500 I ever raced against was a BHP engined Spitfire. Had a "H" pattern block girdle for stiffening with special dry sump pan. A rocket on the straight and a terror to get whoaed down for the bridge at Road Atlanta. Scared the begeebers out of the guy. Of course, the bridge got a lot of respect from drivers, including me. Never heard what the guy had in the diff.

Don't know about the 3.55 fit up, but try it, put the prussian blue on it and see where everything lines up.

Take care,
MIke
 
Are the 4.22 gears in a banjo rear, same as the 3.9 in the early MGBs? PJ
 
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