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Another Circle "B" head question

gjh2007

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I posted on the six pack some questions about the spare motor I have along with a spare head some questions about the castings on the heads.

I got a response from someone on the six pack asking about the Circle "B" casting & that it was from the european injected cars & it was desirable.

That would seem unusual as it is on the spare engine I picked up last year with a very low block #. Also the intake/exhaust gasket I have fits both heads. The engine was supposidly out of a trashed TR250.

Should I pull the B head & have it rebuilt & put it on my exist engine?

Any input/suggestions would be appreciated.
 
well, thats sorta true. the late model tr6's and the tr250's had the wide spacing on the ports which is what was used for the injected engines. really there wasnt anything special about the engines themselves just as long as it was the wide port head. the late model tr6 heads are the same casting, but were thicker and had air injection ports in them. they were thicker so the compression ratio was lowered for emitions. it depends on what year your car is on if this head will make a difference. there is a good article on the flows of these heads but i couldnt find it with a quick search....anyone else know the one im talking about?
Randy
 
I'm confused as usual, that means it sounds like both the extra engine complete & extra head I have are wide port, if the manifold gasket fits both? Did you mean early TR6 & 250, not late TR6?

I await further input.
 
Make sure the gasket does fit both. All gaskets will fit onto the studs. Where the difference is, is in the intake ports. Make sure the gasket doesn't partially cover the port opening.
 
Thanks, will take a closer look.

Also if it is the wider port, that means my early model intake manifold will not fit, correct?
 
OK, looked at the head that's on my extra engine & it appears to in fact be a narrow port circle B head. Do I pull it & have it rebuilt instead of using my existing head?
 
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