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MG MGB Technical - 2 cylinders

Is it possible to run a mgb engine on just 2 cylinders ?

The reason i ask this is that i have a gunsons gas tester coming very soon,now we all know that these units are very good at reading the C/O level which the engine puts out,but the result is from both carbs,so do you think that it is possible to take out no 3 & 4 spark plugs and run the engine on the front 2 cylinders only and set up the front carb,then repeat the process for cylinders 3&4 and set up the rear carb, thus reaching a perfect balance for each carb.

what do you think ? is it possible.
btw 1978 mgbgt hif4 carbs.
phil mcneil

In a singel word, NO. If you look at the intake manifold you'll see that there is a significant balance tube connecting the carbs, you would only upset the mixture if you didn't have normal draw on both sides. I've seen 4 cylinders run very roughly with cylinders 2 and 3 plug wires crossed, but never seen one run with the front or rear pair of cylinders dead, something about the firing sequence and the crank positions that just seem to make them not want to run that way.
Bill Young

Thanks Bill,it was just a thought,suppose i'll have to be paitent with the colour tune.
phil mcneil

Aside from which, the unburned air from the dead cylinders would ruin the readings.

Jim Blackwood

Yep. Carbs have to be adjusted only when everything around them is working perfectly. There is, however, a nice cheap tool called a Unisyn which is designed specifically to get the carbs properly balanced.

If you really wanted to run on two cylinders remove the pushrods for the two cylinders in question.

Barry Parkinson

MG removed the pistons (first 2 then 4 from a 6 cylinder) for a series of record breaking runs in three different engine classes.
Paul Hunt 2

This thread was discussed between 05/02/2007 and 16/02/2007

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