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MG MGB Technical - 18GG vs 18V582FH - Differences please!?

Hi,

Looking to bid on a rebuilt short engine. It is engine number 18GG-RWE-H8380.

Car has a 18V582FH fitted. Can anyone tell me what the difference will be as a short engine. Can I use all ancillaries (maybe not distributor). What changed between them when considering the block and pistons / crank only.

Many thanks - Ebay item ends tonight !!

Andrew Walton

I done a quick Archive search on 18GG and the first thread has some info (I didn't look further)

look at the thread called '18GG RWE differs from 18V582F' among others
Nigel Atkins

There is a difference in crankshaft construction although their interchangeable. The 18V went to the straight cut conrods whichment are an improvement over the old angle split rods. There is also a slight change in the oil pump/distributor drive. Denis
Denis4

Many thanks both. Decided not to mix and match parts - it can only end badly !!
Andrew Walton

Late 18GG also had the straight cut conrods, with floating gudgeon rather than press fit as per 18V. The crankshaft change also happened at that stage too. Approx 1971 I think. Certainly 1971 Landcrabs had these features so presumably they happened to all B series 1800 blocks at the same time.
At the same time, there was a block mod which gave enough room to withdraw the camshaft without having to drop the oil pump.
18V has bolt-on mains, not studs.
Paul Walbran

Most of the stuff is interchangeable. For example, I've an 18GB engine in my '72, but when a big end turned in the end of a rod and mangled the 18GB crank, I swapped it for a reground 18V one. Then many thousands of miles later used 18V rods/pistons instead of the 18GB ones.

I understand the 18GG rods have the advantage of using the circlip type pistons, but having the strength of 18V ones. Important if you want to do a 1950cc conversion with Lotus pistons.

Peter
P A Allen

This thread was discussed between 02/04/2014 and 03/04/2014

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