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sooty plugs

Opinions please!

the v8 in my TR7 is sooting up the plugs a treat. It's been away for a new camshaft and a session on the rolling road. Having been back for checking once after it began running like shit, the guys who did the tuning on the rolling road can find nothing wrong with it, in terms of emissions, mix or whatnot.

The plugs however, are still black as night after a couple of days (about fifty miles or so). I'm using NGK BP5ES plugs, which I've had confirmed as the right kind by several independent TR7/v8 knowledgeable people.

What can I look at next?

It's a stock 3.5, with a Holley carb, and uses an electronic box in place of contact breakers in the distributor, with a Lucas coil.

cheers,

Reply to
James Dore
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Can you still get plugs in graduated heat scales? Long time since I was amongst it. Used to be able to buy 'cool' and 'hot' plugs. DaveK.

Reply to
davek

He is already using a very hot running plug with an extended nose. Sounds more like something basic to me, if there is lots of unburnt fuel there is either a massive fuelling problem or it is running really badly. Either way the rolling road should sort it out, if the users actually know their stuff.

mrcheerful

Reply to
mrcheerful

Yes, about half an hour ago I spoke to S&S who specialise in TR7v8's - they suggested that the spark may be weak due to a failing coil or somesuch - s**te leads? Is there any means of testing the spark or leads?

Cheers,

Reply to
James Dore

Well you can look at the waveform on the scope, any rollong road should have a crypton scope. Otherwise change the leads, they're cheaper than the diagnosis time.

Reply to
Duncanwood

Gunsons make a very inexpensive spark tester that gives quite reliable answers to how many kilovolt you have available. I expect halfords sell them, they are about 6 pounds.

mrcheerful

Reply to
mrcheerful

You'd have expected a rolling road setup to test & check that - another good start point would be to get a CO test done it. If its not the ignition then it has to be the fuelling in which case it might be time to strip the carb.

I.

Reply to
Iain Miller

open exhaust to me. Steve the grease

Reply to
R L Driver

Runniong badly, due to shagged HT lead on #1 cylender. All other plugs were perfect condition, but that lead fell to bits when I pulled it, and removed the very sooty plug.

Reply to
James Dore

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