do you guys widen or close the spark plug gap relative to "age" of a motor. example; new motor within specs/tolerances use fsm spec gap. Old motor running loose, do you widen or close the spark gap. What typical spark gap do you use?
plug gap vs. "age" of motor
- Thread starter beaufort-fj60
- Start date
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Beaufort;
From a purely theoretical point of view, as the engine ages, going to a larger gap will create a hotter spark; but u can only go so far, because u can create an over voltage problem that reflects back to the stock coil, which can create high voltage windings (secondary coil) arcing and short circuits.
Put a capacitive discharge unit (like Jacobs makes) on an old engine and it will run like new, or better.
...
From a purely theoretical point of view, as the engine ages, going to a larger gap will create a hotter spark; but u can only go so far, because u can create an over voltage problem that reflects back to the stock coil, which can create high voltage windings (secondary coil) arcing and short circuits.
Put a capacitive discharge unit (like Jacobs makes) on an old engine and it will run like new, or better.
...
- Thread starter
- #4
I changed the plugs out yesterday. A few of the cylinders were running hot and a few were oily. The engine has 252,000 miles on it, but runs good enough for daily job site use. Was curious if anyone custom gaps problem cylinders. When and if the motor dies I plan on having it rebuilt, but until then I am going to get every bit of life out of it.
you can wring a little more life out of your engine with RESTORE engine treatment. It'll smoke the first time you start it up after pouring it in the engine but then everything seems to seat up nicely. I expect to see 300k in a few years.
My opinion and what I do ...
I gap at 0.035 for both of my trucks. One is a stock coil and the other is HEI. The plug gap will affect the longevity of your coil. This thread should be 'Plug gap vs. "age" of coil'.
People get all weird about plug gap. Correct maintenance is more important. Yes you can run a wider gap and get a hotter spark but you are trashing you coil and that turns into dependability ???
Cheers & HTH,
Cahil
I gap at 0.035 for both of my trucks. One is a stock coil and the other is HEI. The plug gap will affect the longevity of your coil. This thread should be 'Plug gap vs. "age" of coil'.
People get all weird about plug gap. Correct maintenance is more important. Yes you can run a wider gap and get a hotter spark but you are trashing you coil and that turns into dependability ???
Cheers & HTH,
Cahil
beaufort-fj60 said:
Smart move.
It comes down to physics. Within reason you can improve marginally. I really like the HEI because I can get parts at almost any auto parts store if I need them. Is it an improvement over the stock Toyota ? Would be an interesting discussion. Downfall is I'll probably need parts sooner rather than later if I had re-installed *new* Toyota stuff. But 20+ years on the same ignitor/coil has me a little worried.
Eventually you get to a point similar to burning a candle.
The candle which burns twice as bright burns half as long.
Cheers,
Cahil
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I gap to .055 and noticed an immediate improvement.
Tinker said:
There's a whole freakin' science about ignitions and I know enough that I don't know enough.
Bascially in layman's speak here's is my best attempt.
The larger gap makes the coil work harder to bridge the gap with a spark thus having a larger & hotter spark. Upside, better performance. Downside, longevity or your coil and potentially parts of the ignition system because of the increase in current.
It's a balanced environment.
Yes you can re-gap and have an immediate performance increase but trust me ... it is costing and balancing out somewhere else in the system.
It's all about trade offs and what you are willing to sacrifice for the performance increase.
HTH,
Cahil
Fearnofish! said:
Excellent !!!
Just like me when you or I need a replacement coil we can go to pratically *any* auto parts store and they will have it in stock.
Cahil
P.S. I'm still stickin' with 0.035 for coil longevity.