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Engine Color options

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Hap Waldrop said:
Here's look at the BMC olive green on a Spridget motor.
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I recognize that motor!
grin.gif
 
vping said:
How about clue #2 for tht "X" head :smile:
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Casting #....

12H1326
AF1H

or....

12H1326
AF1
 
And if those are "X" heads on the blocks they are not crossflow. Hmmm...
 
Those are "X" heads on those blocks!
 
They all look the same with all the correct holes for bolts and sending unit. All early type and presmog. Are they taller? Not sure unless there was a non-"X" head next to it for comparrison.

This is a good one Tony.
 
Hap, you need to find some sort of transparent paint so that we could get a view of all that eye candy after it's all assembled and not hide it inside some cast iron. Nice bits and great work.
 
Putting an early "X" head & an early standard head side by side, there's no difference....the early standard head has this casting number:

12H906
AF1

I can post some close-up photos of the 2 heads side-by-side....but, I'm still not telling the real difference!! hehehe

<span style="font-style: italic">(Oh, & one of the popular MGB web sites has incorrect information/numbers in its head comparison table so you can't use it to figure out what they are.)</span>
 
Is it an MGB head? or from another car?
 
The "X" heads are off MG's (MOWOG)...so is the 12H906 standard head....ready for another hint?
 
As you and I both type - I'm on my lunch searching the internet and am still drawing a blank. Continue - you're move!
 
hehehehe......."X" heads = European castings....not offered in North America.

I'll let you go from there.
 
tony barnhill said:
hehehehe......."X" heads = European castings....not offered in North America.

I'll let you go from there.
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NAH, this has been fun.....but, here ya go:

They were European offerings...back when there was a rash of cracked heads, lots of dealers had these sent over from salvage yards in the UK, rebuilt them & put them in customer cars. Here's the difference between them & NA heads:

1. The combustion chamber is smaller so it increases the compression ratio.
2. The intake valves are larger than any valves offered in NA heads.
3. The head flows gas smoother.
4. The area around the exhaust guides is larger than the area in normal heads so the exhaust also flows more smoothly.

When customers got their cars back (usually heads replaced under warranty) they were excited about the increased power. Remember, these are non-emission heads.

......& if you can't find an "X" head, look for an "O" head! :whistle: hehehe
 
Other than the casting number and looking at the valves, how can you tell from the outside it is an "X" head?
Were the casting numbers in any sequence like from #123 to #456?

OK I'll take the bait, what's an "O" head. And don't tell me it's something like a left handed metric adjustable :smile:

You should move this over to the PUB. It's good reading and engine color can apply to any and all cars not just MGB's.
 
Where the later "L" & "H" heads have those designations, these heads have an "X".

Oh, on the "O" head....hehehehe
 
I kinda figured that what it might have been. My GT has an "H" my Roadster has the "L". No "O" that I know of. Does the "X" or "O" stand for anything like the low and high compression heads?
 
No, the "X" symbolizes all the things I explained above...."O" is the same way for that head's differences.
 
Tony what is the intake valve size on a X head? What is the combustion chamber volume on a X head?
 
Good question.

I like that gray/black engine combo BTW.
 
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