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Two engines - Which should I remanufacture?


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I have a GT6 Mk3 engine that came out of a car that I am restoring. It was running before I started the restoration. I intend having the engine remanufactured. However, I'm concerned that the block looks like it has previously been skimmed.  It's missing its engine number and has a thick aluminium head gasket fitted.  I have another complete GT6 mk3 engine that has been in my garage for about ten years. I'm not sure if it was a runner but it looks dry, a bit rusty and complete.

 

I know it might be a difficult question to answer, but is the first engine suitable to remanufacture or should I go with the second one?  In some ways I wish I could take the best of both to make one good one.  What do you guys think?

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Impossible to answer without dismantling the engines.

 

The block skimming would have been either to deal with damage to the face (unlikely) or to "deck the block".

This procedure also involves skimming the crowns of any pistons that are higher than others, and then the block face, so that each piston rises exactly as far as the others. Any sign of that on the piston tops - loss of normal markings?   The objective is to have them all rise to the top of the block face, which production engines don't achieve - all part of 'blueprinting' a competition engine.

 

The thick alloy gasket - how thick?  To compensate for an over-skimmed head, that raised the CR too much, would need a gasket less than a millimeter thicker than normal, almost unnoticeable.    I suspect that this was used to LOWER the compression below normal to allow forced induction.    Could be turbo, but people have put superchargers on Triumph sixes.  Such a gasket may be several millimeters thicker  Anything on the car that might corroborate that?    Mods to the exhaust and intake?    Extra pulleys to drive a 'charger?

 

If that was the case, then the stress on the pistons, conrods and especially big-end bearings is enormous, so look carefully at those.

 

Your other engine - does it turn over or is it seized?    You could free it up, by soaking the bores in oil and paraffin or white spirit for a few day and then turning it backwards and forwards  until it freed up.  Spark plugs out, of course.  No point in dismantling if you can't free it. 

 

OR, just take both to the engine rebuilder, Let him choose.

 

John

 

PS if you don't want the other one - will you sell it?

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