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MG MGA - Engine type ?
| There is a 1966 B engine on ebay (18 GB-U-H28238)can anyone tell me if this is a 3 or 5 main bearing please as I cant tell the diferance, thank you, Vin, By the way, I think the clockwork mga in the " simple supercharger" thread looks great lol | 
| Vin Rafter | 
| Hi Vin, 18GB was the first of the 5-bearing engines. Only 18G and 18GA were 3-bearing, and I believe the last year of 18GA was 1964. Regards, Andy | 
| Andrew Dear | 
| > 18GB was the first of the 5-bearing engines. Only 18G and 18GA were 3-bearing, and I believe the last year of 18GA was 1964. Correct. | 
| Andy Bounsall | 
| thanks you, | 
| Vin Rafter | 
| can you tell me what if any, is the difference between the early and later 5 main engines, thank you again, Vin | 
| Vin Rafter | 
| It takes some reading but most of the differences are in here: http://www.sterlingbritishmotoringsociety.org/files/mgbtunings.PDF | 
| Willem vd Veer | 
| See http://www.mgexperience.net/article/mgenginehistory.html and scroll way down to chapter 7. | 
| Andy Bounsall | 
| The GB engine was the first 5-main bearing block and crankshaft. It was mated to the 3-synchro gearbox for a few years ('65-'67) using a small diameter flywheel that fits the 5-main crank. You would need this particular flywheel to mate any 5-main engine to any 3-synchro gearbox. Starting 1968 came the larger 4-synchro gearbox and larger diameter flywheel. | 
| Barney Gaylord | 
This thread was discussed on 09/08/2010
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