I appreciate the historical richness of your experience. Let me make up some dates & numbers: say in the '80s after-market inventors came up with a super coil that would give your plugs a charge of 10,000 volts instead of the 1,000 that the car was designed to have & you got better performance and economy [if the engine did not blow up]. But in the '90s the on-board computer made such aftermarket changes more difficult. So Pulstar came up with a super plug that gave you 100,000 volts, instead of the 5,000 the car was designed for. Well I ordered 5 of these expensive plugs & one was bad & my onboard computer told us which one was bad - we reinstalled one of the old ones & sent the bad one back & Pulstar promptly sent us a new one. We installed that & the performance was not noticeably better [like in my brother’s Lincoln] but my MPG went from 20 to 28, but after two tanks of gas, it went back to 20. My suspection is that the onboard computer in my Volvo v70, detected the super-hot spark & somehow reduced the pulse from the coil so the end result would restore things to the way the car was designed. What do you think?

I think there was error in you gas mileage measurement. You never had any improvement. The computer does not adjust spark plug voltage in the way you suggest. The pulstar plugs are snake oil, and don’t help anything. In fact, there is a good chance that over time they will damage your coils. BTW, your voltage figures are way, way off.
Also, why do you think that a hotter spark would make any difference anyway?

what is BTW? I just made up those voltage figures or a discussion point. Only the MPG was actually & accurately checked.

Every aspect of your thinking on this matter is wrong, every little bit. Your numbers and reasoning are all incorrect. Don’t waste your money on “super” plugs or anything else if you want optimal efficiency, just stick with original equipment.

BTW = By The Way
How did you accurately check the mileage? You can’t do it for just one tank full by measuring the amount you put in and checking the odometer. There will always be some variance in the full level of the gas tank. You can average this variance out over several tank fulls, but you could easily have the 8 MPG error you indicate on any given tank.

Dear OP:

After reading your post, I can’t decide if you’re asking a serious question or if you’re yet another Pulstar shill trying another creative pitch.

Pulstar plugs have been discussed in great length. Many before you have spent their hard earned money. And in the end they learned that it’s only those selling Pulstar plugs who come out ahead.

All: Given the price of gas has been inching up over the past 6 months, does this mean we’ll now see a resurgence in these scam pitches?

For all practical purposes, a spark plug either ignites the mixture or it doesn’t. Increasing the spark plug gap may change the timing slightly, but the effect is usually negligible. It seems to me that when we used to have mechanical igntion points and some people adapted an electronic ignition system to replace the ignition points, the spark plug gap sometimes had to be increased to overcome what was called “short spark”.

I’m a great fan of the Champion J-8 spark plug. When I was growing up back in the 1950’s, we could use a Champion J-8 in every engine from the 2 cycle LawnBoy mower and the 4 cycle Briggs and Stratton roto-tiller engine to the 1954 Buick and 1952 Dodge engines. The two cycle LawnBoy had a habit of being hard to start after the engine had been running. I always had a spare J-8 plug and a pair of pliers in my pocket, and a quick plug change and I would be running again. I would switch the plugs back the next time I found the engine hard to start.

I admire your optimism. But your voltages are way off and your perception of a “super hot spark” (or even a change in the temperature of the spark) is incorrect, as is your theory of how the car’s systems work.

The car’s ECU adjusts for many things, among them manifold pressure, air flowing in, engine speed, even knock detection, and ratio of oxygen in the exhaust stream, but it does not measure or adjust for cylinder or spark temperatures. And, as others have stated, good detonation either happens or not. Your OEM sparkplugs provide excellent initiation of the combustion process, and as long as they’re in good shape that can’t be improved upon.

As a matter of fact, you have an EGR system designed to prevent the temperature of the cylinders from getting TOO hot under load. If you DID up the combustion temperatures the engine would ping or knock and your ECU would make some adjustments to try to stop the pinging at the expense of efficiency…

But I admire your optimism.

Thank you, I do appreciate the time you’ve taken to share info with me. Remember the voltage numbers I used are entirely made up - just for example…

Pulstar plugs are a scam. They’ve been around for 15 years or so because why? Because people buy into the marketing hype.
If those plugs actually improved fuel mileage even .1 of a MPG then every engine producer on Earth would be furiously buying them in bulk and installing them from the get-go.

There’s some placebo at work here (the Pulstar business plan) and your car’s fuel mileage did not improve; much less by 8 MPG.
Other than the voltages you cite being wrong, your understanding of how a spark plug works is also flawed.