Welcome to our resource for MG Car Information.



TR parts and Triumph parts, TR bits, Triumph Car Spares and accessories are available for TR2, TR3, TR3A, TR4, TR4A, TR5, TR6, TR7, TR8, Spitfire and Stag and other TR models are available from British car spares and parts company LBCarCo.

Triumph TR6 - Spark Plug Setup

I installed a new MSD 6A ignition yesterday and experienced a very noticable engine performance increase. So then started to look at the MSD spark plug gap recommendations which said to increase the gap to .050 at compression ratio's less than 10.5:1

I found that at the wide gap, performance dropped off with a high speed miss so put the gap back to around .037

Could folks write in with thier compression ratio, spark plug make and model and the gap. I'd be interested to see what others are running.

My plugs are the Bosche Platinum's, my CR 9.5:1, ignition Crane XR700 optical points with the MSD.


John Parfitt
Calgary, Canada
73 5 Speed.
John Parfitt

Hey John,

I have essentially the same set-up as you:
Bosch Platinum's
9.5:1 CR
Crane XR700

And yup, I gap them around 0.037"
Brent B

.040 with the Crane and the Lucas Sport Coil. Champions. Stock engine.

Jim Deatsch

9.5:1 CR
41352 w/Pertronix
Lucas Sport Coil
MSD Wires
NGK BP6ES @ .040#


8.5 CR
Pertronix el
Pertronix 'Flamethrower'40,000v coil
NGK BP6ES - 0.045" gap
Ballast removed.

Peter 74 TR6 w/ 73 spec engine
Peter Gooch

This thread was discussed between 01/09/2003 and 02/09/2003

Triumph TR6 index