MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGA - MGA 1500 with MGB 1800 Head??

What if any are the advatages of intalling an early, (pre 1975), MGB 1800 series head on a 1500 MGA engine?

I am rebuilding another 1500 MGA motor, and my local shop has an early MGB head already completed, (shaved, new rockers, new springs, new valves, new shaft, etc).

I can buy it cheaper than sending mine out, and it's already completed, ready to install.

Any draw backs? Any pluses? Any ideas?

thanks,
DT
Danny Thomason

The combustion chambers are a little bigger, so compression ratio will be down a bit, but if it has been shaved a few times, then it won;t be a big difference. The bigger valves are a benefit. Make sure it is a 1326 (there is another one but I can't remember the casting number, search the archive as I posted the link in a recent thread where someone was asking about the hole for the heater valve) to avoid the valves meeting block.

If in doubt, you have to mill eyebrows in the block to avoid the valves hitting the block - use the head gasket as a guide to the shape or check the ususal resources.
dominic clancy

The link is here the first two are the castings to use without eyebrows in the block

http://www.flowspeed.com/cylinder-ident.htm
dominic clancy

I cracked a head on a 1588 and replaced it with a 1800 land crab head. Seemed to go just as well as before, lower compression / Larger valves.

If the thickness of the head has been reduced, make absolutely sure that the valves do not come into contact with the top of the block. Use a 1800 head gasket.

Cheers
ian F

Ian Fraser

This thread was discussed on 24/05/2006

MG MGA index

This thread is from the archive. The Live MG MGA BBS is active now.