13 replies to this topic

[germini30]

Got an mg metro engine fitted. I noticed a crack below where the tappets sit. Would I lose much poke by fitting a standard head as I have two here.

[germini30]

Pics

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[racingbob]

Don't think you would notice much

[germini30]

Ok. My engine is smoky on overrun. Looks like valve stem seals. I was going to build the other head ready to swap.

[Cooperman]

If you are going to rebuild another 940 head you can get 35.6 mm inlet valves and it will be the same as the MG Metro head. Don't forget to measure and calculate to ensure the compression ratio is correct.

[germini30]

I have a standard 12g940 here, just thought that I could make use of it but was wondering if I would notice much of a drop in performance.

[Pigeonto]

Done that, had to put a std head back on to a bigger cammed twin carb engine due to bigger valved one failing, and the only difference is full bore ,4500 rpm and upwards. Nice torque up til that point. The compression ratio will remain as per MG if the block is standard

Edited by Pigeonto, 17 August 2017 - 08:56 AM.

[germini30]

I dont go in that rev range much anyways. Was it a big difference?

[Pigeonto]

As yourself, I don't go there very often (though I did on Sunday up the strip   ) ! I was quite surprised how lively it was in normal driving, only time I really noticed the loss was at 70 /75 overtaking with the wind resistance. Winding it up through the gears, not much. Bear in mind that the later MGs had the smaller inlet valve once unleaded fuel came in

Edited by Pigeonto, 17 August 2017 - 09:36 AM.

[Dusky]

In noticed the difference between 33 and 35mm vakves, do the other way round Will be noticable too.
But, as you already have the right valves etc it'll be cheap enough to get 4 valve Seats recut.

[germini30]

Aslong as there would be enough metal left I suppose so.

[ACDodd]

That can be saved fir around £75. It needs an inert if metal to fix it.

Ac

[germini30]

Ok. I have 12G940 heads in the garage. No.idea what they are off plus there is a 998cc with 12G295 on it. Any ideas what these heads are?

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[carbon]

Left hand picture is A+ 1275 head (possibly with sheared off thermostat housing bolt)

Right hand is pre-A+ 1275 head