Ignition timing

[gqroo]

Gday just want to know wat plug gap to run, at the moment its 1mm since ive done that i seem to have a flat spot when i punch it around 2500-3000.Also does 14deg sound bout right for timing.
thanks
Lou

[gqroo]

Sorry tb42 duel fuel pertronix.

[Sterlo]

Well mate try closing the spark gap again see what happens.


.8mm is the "norm" for most applications.. It is hard on a duel fuel application.. Also check plug leads, dizzy rotor, cap for burn marks. Gas is hard on these items, including coil and module. It is takes a lot more energy to fire and burn gas than petrol. High tension sprak problems are a lot more apparent under load situations.. Also 15degrees sound perfect for gas but petrol to me may cause pinging.. Worth a thought, let me know how you go

Sterlo

[Artificial_Aspiration]

I ran mine at 22 deg adv on gas with the vac line disconnected. It loved it heaps more torque down low, no pinging, smooth power all the way to 5500rpm. I was getting 18lt to 20 lt per 100km around town.

[da60]

I have a dual fuel set-up and run 20' advance and get good performance on Gas and no pinging on petrol (vacuum line connected) although I do run premium unleaded. A standard points ignition with genuine parts (not too expensive and a better quality points) and Bosch super 4's.

[gqroo]

Did my plug gaps again back to .35, went to do timing and t/light shite itself.Took it for a drive after work tonight still had a backfire @ 3000rpm hopefully just timing, though i was talking to phil @ ontrack he said it might even be a faulty elec ignition, dont think it will be, today will tell.

[Sexy Fingers]

Spark plugs come pre gapped these days, but 1.0mm is a good gap for an lpg system. Timing sounds about right too. Does it flat spot on petrol or gas? With the backfiring, it does sound like it may have an ignition problem. Start with checking the lead resistance (no more than 12K ohm on each lead), and as already mentioned, you may want to check the rotor cap and button, and igniton coil.

[gqroo]

COIL END OF LEAD BURNT OUT, THANKS FOR TIPS,ive just used a spare plug lead i had its about 1mtr long,does length matter? Mmm

[Sexy Fingers]

does length matter? :

no

[Batcho Snr]

I was having backfire & flatspot problems with mine particularly in sand on low rev's. Fitted a GT40 coil & Piranha electronic kit (to replace the standard points and condenser) & the problem was 99% fixed. Also found that the tappets were too tight & I had no valve clearance at all. Now running like a dream.