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MG MGA - Spark Plug Gap

I just wanted to check in to see what gap you are running.

I've just switched to Autolite 63's

Also what torque setting do you use for seating the plugs.

Thanks
Tysen McCarthy

I should also probably mention that I'm running a Petronix Flamethrower Ignition Coil
Tysen McCarthy

Hi Tyson

Nice to see you back.

Most plugs here come pre-gapped at .6mm and I just leave them as delivered. To install I just nip them up tight, no torque or levering on the wrench, just screw in and then a slight tug on the wrench to tighten.
dominic clancy

Tysen

I am basically with Dominic especially with the standard coil. However, if you have also fitted the higher output coil there is an opinion that the gaps can be opened to as much as 35thou. I set mine to 30 thou.

Steve
Steve Gyles

Thanks Dominic! The boys are older now and starting to leave for college so I have time again to put into the old girl. Plus all the work I did 7-8 years ago needs to done again.....
Tysen McCarthy

Guys
Spark plug tightening torque is commonly misunderstood It is important to have them tight to allow for proper heat transfer from the plug back into the cyl. head
The correct tension for a gasket type 14mm spark plug is 25-30Nm
William Revit

Dominic, et al: I always check the gap on new spark plugs "out of the box". I did once just installed new plugs without checkin the gap. The car ran awful. Pulled the plugs and found the gaps were not consistent.

I have checked the gaps ever since and found variances many times. The plugs may leave the factory door correctly gapped, but who knows what happens to them while in transit and being re shelved at a distribution centers and retail outlets.

Cheers

Gary
79 MGB
gary hansen

FWIW, the reason I asked is that I had gapped the plugs to .032". For whatever reason I just didn't like the sound or feel. (Hard to pin down those subjectives)

In any event, after re-gapping to .024" the sound is noticeably less harsh.
Tysen McCarthy

The MGB Workshop Manual gives the torque setting for spark plugs as 18 ft lb. I assume it should be the same for any MGA engine (twin cam may be different).

Jim
JL Cheatham

This thread was discussed between 05/09/2016 and 09/09/2016

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