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Pertronix and Timing

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carrottop

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Had a friend install the pertronix kit and high performance coil. Car starts much more easily. But I have noticed a ping and some loss of power as the car started running hot as in over 210 degrees when it never went over 190 in the past. So I tested with a timing light and noticed the hash mark at 12 oclock or at the top of the wheel when I started up the car. Adjusted the distributor a touch counter-clockwise, idle reduced and the hash mark is further away at 1 oclock. Have I retarded the ignition? That was my hope as I've read that may reduce the ping.

What is the correct adjustment position and is there a reference guide on this? My Healey manuals don't seem clear on this.

Thanks,

Eric
 
The timing should be before top dead center. I don't have my manual right now so I can't tell you exactly what it should be. The timing light should be on at 11 o'clock or so. Retarded timing causes overheating. Advanced timing causes pinging. You don't want retarded timing. You should be using mid-grade or premium fuel to avoid ping.
 
The manual reads 15 degrees BTDC which I assume matches the arrow and the hash mark. I can't get there by turning the distributor without making the car idle poorly. I have read the widening the spark plug gap will help. Something is not right.
 
carrottop said:
The manual reads 15 degrees BTDC which I assume matches the arrow and the hash mark.
Click to expand...
No, when those are lined up, you are at TDC. If you do a search, there is info on how much distance from the pulley mark 15° is.
carrottop said:
I have read the widening the spark plug gap will help.
Click to expand...
Maybe, maybe not. Too much gap and the plugs might not fire.
 
Thank you for all your help and guidance. Car starts easily. I believe I have the engine timed correctly but it still seems to idle a bit rough and I notice a high speed miss occasionally. Could this be spark plugs or SP wires that I didn't notice with my old points? Or is it a tri-carb setting issue.

Thanks again,

Eric
 
re: "Could this be spark plugs or SP wires that I didn't notice with my old points?"

Only if you increased the plug gaps to take advantage of the HP coil. The plug gap determines the voltage at which the coil will discharge; often, people will increase the gap with an HP coil, which will raise the firing voltage in the secondary ignition system--the whole point of an HP coil--and expose any weakness in the system. If you didn't change the gaps the firing voltage will be the same--meaning you wasted money on the HP coil--but you may still have some weaknesses in the secondary ignition system or, possibly, you disturbed or damaged a marginal part when you did your mods (like, say, the distributor cap).

I've had problems with aftermarket distributor caps--same symptoms as yours--and will now only use genuine Lucas caps. Similarly, modern super-duper silicone/wound-core plug wires don't play well with the Lucas-style caps and their 'spear' terminals. I only use copper strand plug wire (e.g. 'Bumblebee' type, but black). I use resistor plugs and plug connectors to keep EMI (electro-magnetic interference) to a minimum.

Take a short run at night to get your engine up to running temperature, then park in a dark garage with the engine running and pop the bonnet. Look for arcing on the distributor cap or along the plug wires.
 
Thanks Bob. Will test run and try the dark well ventilated garage test. Should the SP gap be increased to .45"?

Thanks,

Eric
 
NO 0.o40 is the max reliable spacing for the plug gaps.--Keoke
 
I'd work the problems out first. If you increase the gap you're increasing the secondary voltage--that will exacerbate any problems with the system. OTOH, the 'dark' test might expose the problems with higher voltage. Be advised with higher voltage you can actually burn a permanent trace on the cap that will produce a short even at lower voltage.
 
Ran the car at night and did the dark garage test. No arcing at distributor or wires. Have a Lucas side entry distributor cap. But did notice something that may be the cause. My friend who installed the pertronix kit in the dizzy and also new HP coil used electrical tape to seal the coil wire connection to the coil as the old coil connection was different. Pulled off the wire to the coil and saw the frayed wire ends and of course no boot. Wires are fine all round but would consider replacing although don't believe it is necessary at this time. Is there a termination kit for the sp and coil wires? Also have no idea how to install the sp and coil wire to my side entry dizzy cap.

Suggestions please and thanks,

Eric
 
Well if your friend did that rigging without telling you, I'd think twice about letting him work on your car again. You might check where you bought the coil if they have the proper end piece for your coil wire. Even the HELP! section at Pep Boys has coil wire ends that may work.
 
Well, he ran into a problem. My old coil has a boot that screws into its neck. The pertronix HP coil has the traditional snap on style. Guess I will have to call them for a remedy. My local Pep Boys "Help" section had no coil ends.
 
:savewave:

Hey hold on there a bit.There is nothing unique about the tip used with the modern coil just about all older car high tension leads used this same type connector on the end. I am ure that they can be obbtained at most auto stores. So go back and Look again. Even a junk yard will yield them for you.--Keoke
 
Went back again and still no luck. Pep Boys had single pigtail leads for the coil but didn't want to use a right angle boot. Should I find a pigtail that would fit the coil, how do you terminate the other end of the wire that goes inside the side entry distributor cap. What keeps the wire in there? Eric
 
Hi Eric,
If you have the original style side entry dizzy cap, there will be screws inside underneath that lock the wires in place. So the cap will need to come off to do this. It also means you should get copper core spark plug wires. The silk/carbon wires will breakdown after a short period of time. If you can't find the parts locally, you may just need to order them, perhaps even a full set. If there is a speed shop in your area, they will probably have what you need and they will able to help you more than the auto chain store clerks. Another option at the chain stores would be a universal plug wire set that you would need to cut to fit.
 
Carrrottop:
Yeah Greg, he will need solid stranded wire to properly anchor the high tension leads in the distributor cap using the integral screws. However, terminating the Coil wire to Dizzy cap at the coil should be a no brainer. the crimp type terminals should be redily available I would think.
 
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