Ignition Timing

[Andes]

Cheers Terry, don’t want to spend more money than necessary or start messing with things that lead to messing with more things and the car ends up in bits.......next job, set timing then enjoy 😁

[DJT]

Ok, I can now put some figures out for info.

Ive just had my Mk2 distributor refurbished and calibrated by The Distributor Doctor. Fitted with a new vacuum unit, DD rotor arm, genuine Lucas cap and Pertronix ignition.

Using a �dial in� type of timing light I have it set at 14 degrees BTDC at tickover. Increasing the revs to about 3000, the total advance (including vacuum) is 40 degrees BTDC. At least, that is what I have to dial in on the timing light to return the timing mark to TDC.

The engine sounds as sweet as and ticks over smoothly at 750rpm.

[trunt]

Thats handy info. So what do you see at 3000rpm with no vacuum pipe? Should be about 30 degrees?

Terry

[DJT]

Haven�t tried it. Just come back from a run to the coast with SWMBO on board and found that the engine is not pulling properly. Reluctant to rev above 3000 and misfiring. Got some investigating to do tomorrow..........

[trunt]

Damn cars! Well the no vacuum test is valid for that kind of thing, normally they will drive fine without vacuum advance, as long as you plug it at the carb - worth a try?

Terry

[DJT]

What a b****y day! Tried various things to eliminate the misfire, then went back to my old dizzy and Lumenition. Fault still there! Much head scratching, then I hit on swapping the plug leads with an old set I had in my spares box. Problem solved. Now back with the new dizzy and Pertronix fitted and all seems good. I guess one of the HT leads didn�t like being messed around and went on strike. I�ll be ordering a new set of leads this week.

[CJG]

Glad you got it sorted Dave, but is it me or do plug leads these days seem a bit more temperamental to what they were in the past on cars of this period.

[DJT]

After fitting the new leads, etc., the car still had a misfire under load. Having tried everything I could think of I finally looked at the plugs today. I was intending to do so, but two Stag owners suggested this last night as well, so.....

I didn't look at these before as the previous set of Champion plugs lasted 25,000 miles without a problem. This set have only done 6,000. I popped down to ECP this morning and bought 8 NGK BP5ES plugs and have fitted these. Misfire now gone............

One thing I noted with the plugs I took out was that the tips were very white, so it seems I may have the carbs running a little lean. On the plus side, all 8 were exactly the same, so the carbs must both be adjusted equally.