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MG MGB Technical - MGA head on an MGB?

I have a 1500 MGA cylinder head and an MGB 1800 5-main block with no head. Can the two be put together without disaster?
M.E. Whalen

Disaster, no but not a good idea as the chamber design is restrictive.
Chris at Octarine Services

Valves are smaller and chamber volumes also.
Art Pearse

The way most people drive today, what's a few horsepoppers? Most of the cars IO see never go over 300 rpm, sad state of affairs. At that, the smaller ports and such probably help. I had a customer with a bitsa, 77 W/ a 1500 head - ran like a scalded cat No idea what else may have been done inside.

FRM
FR Millmore

3 *hundred* rpm!? :o)
Paul Hunt

Paul-
Well I meant to type 3000, but the way these people shift I had to get 4 words on by the end of the garden! I've had people surprised when I tell them it really won't hurt the car to go over 2000rpm in lower gears, and that that alone will cure much of their problem.
It's really painful to get a car all sorted, then have the owner pick it up and shift to top by the end of my property = 125 ft from the drive - and it's a good upgrade. getting rapidly steeper for 1/4 mile.
Sounds like this, (car usually rolls backward as they reverse out):
"Thanks! whaaa; rup, rup, rup, unca, uncaa, unncaa, uunncaa, uuunnncccaaa."

FRM
FR Millmore

What should it sound like? I was thinking:

aghhhhhhhh, maaaaaahhhhhhh, waaaahhhhhhhhh, brrrrraaaahhhhhhh
C Briggs

'At's more like it!

FRM
FR Millmore

I've done a couple of MGA heads for MGB customers and it can be made to work, but as a direct swap it wouldn't be a very good idea as far as outright power is concerned. The chamber volume I believe is not actually that small, in spite of the apparent "closed" form of the chamber itself. They are in fact quite deep.

The ports are very comparable to a 12H-906 casting, though the exhaust port has a bit more of a boss protrusion in it, I wouldn't view that as a major hindrance.

I have some information on the different MGB heads here:

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

Sean
Sean Brown

I ran a 1500 Magnette head on a 3-bearing MGB block for years.
However I did fit larger valves, cleaned up ports etc.

David
David Overington

This thread was discussed between 30/09/2009 and 16/10/2009

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