Plan to pick up some plastigage this afternoon and disassemble the crankshaft. Reading the information in Tech Wiki, the "bearing crush" tolerances is what I will use to determine if the bearings are within specs? And reading the Haynes shop manual the tolerances for end play is only at the thrust (center) bearing? Please explain the "bearing clearance" tolerances. Also I notice a slight lateral movement in both directions on all of the connecting rods, but not up and down. Is this normal? Engine has about 130K miles. Thanks for the help.

Bearing Clearance
* Main: 0.020 to 0.062 mm
* Rod: 0.020 to 0.050 mm
Main Bearing Journal diameter
* 49.951 to 49.964 mm
Crankpin Journal diameter
* 44.974 to 44.961 mm
Journal Taper and out of round
* measure multiple spots
* less than 0.03 mm
End-play
* crank thrust: 0.05 to 0.15 mm
Bearing Crush
* main: 0 to 0.03 mm
* rod: 0.015 to 0.040 mm

.

DD....I am looking at a Delta cam similar to what another MG enthusiast did and that he posted on this thread. His cam is more that what the GX cam spec is (262° duration, .425 lift...A12GX-256°, .331 lift at cam). He is running with the H89 head which has smaller intake ports than the GX head. If I go with the same cam do you see any idling or tuning problems? Or would you recommend going with the GX spec grind?

DD...I have the offset dish and the engine came with the H95 head which I will replace with the GX head. So if I use a centered dish piston will my compression go up?

Ok thanks everyone. I will get a more precise syringe tomorrow and check the cc's again. Will report back later.

Disassembled the A15 block and it looks in real good shape. I can still see the original cross hatches. Engine has about 130k mlies. Will get Plastigage to check bearings and will also check end play. And will also check cylinder bore. If I don't require machining I may want to try and clean the block itself without hot tanking. It was suggested not to do this so that I can preserve the camshaft bearings. Any ideas or methods on doing this? Coolant passages requires serious cleaning.

Might need more help with this. Do I need flattop pistons? I will remeasure today.

DD......checked out Tech Wiki for measuring cc's on the cylinder head and piston. Didn't have a metric syringe handy.....measured 1 oz (29.57cc) for the GX combustion chamber and 1/2 oz (14.79cc) for the A15 piston dish. How do I calculate compression ratio?

DD..second picture from the top shows it. Marked the humps with a marker. Very small compared to the A15 pan. This may be a dumb question...but there is no additional crank shaft movement when its running?? Someone on the MG forum said to use clay and push it against the pan to see how close it is. Any other methods you know of to check this?

Need some guidance on setting an A14 mid sump oil pan on an A15 block. Tech Wiki says it cant be done. The reason for doing this is that the profile is better for my application and according to Tech Wiki the mid sump pan holds 0.4 liters more oil than the A15 pan. The engine is going in a MG Midget. I picked up a mid sump pan from a 1978 B210 car (80HP engine). I marked the crankshaft throws on the mid sump pan because they are not as obvious as the A15 oil pan. When I set the mid sump pan on the A15 block and turn it by hand I cant hear any contact. This is all done on a bench. If anyone has done this before or any other feedback would be much appreciated.

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