A few tips

[JohnnyJerry]

I'm not a regular user here, but I thought I'd drop a few tips that might not or might have been discussed - so bare with me if these have already been discussed.

Side gaping and indexing sparkplugs
Common trick to get free HP, should add to the economy as well.

Hotter sparkplug
Getting a hot or hotter sparkplug will make it heat up faster and obtain optimal temperature.

Low Octane fuel
Inspired by a thread about hot air instead of cold when for eco driving. A friend claimed he got a little extra distance/tank when running low Octane fuel. So the reaction might happen a bit faster getting more power from each stroke. Driving very economical, detonation might not be risky. Now, I have no idea weather it makes a positive effect. Also, high revs on a hot summer day might be a very bad idea on a moderne engine with higher octane requirements.

Low oil
Getting oil at minimum or even lower, will in some cases lower friction from crankshaft dipping in oil pan.
A side effect is also that the oil heats up faster.
Oil temp monitoring might be a good idea if also running on low viscosity, as low viscosity oil draw more heat.

[Ecky]

Good tips!

-Never heard of side gapping. I'll look into this.

-I doubt it's as simple as a hotter or colder plug in a very highly tuned engine, but my knowledge is very limited on this!

-Low octane fuel contains on average (marginally) more BTUs per volume. It's not much, but to my knowledge is is a real effect.

-Low oil makes a ton of sense to me. Faster heatup, less friction. I too run thin oil. I've read studies on it, and engines which switch to a thinner oil actually run cooler; the difference in internal friction is enough to make a measurable difference in operating temperature, but also slows down warmup time.

[JohnnyJerry]

A hotter sparkplug is basically a sparkplug with less insulation. So it heats up faster to optimal temp. The number on the sparkplug code is usually the heat indicator.

I'm not quite sure what difference it will do.

[Taylor95]

I'm sure you would want a colder spark plug if you want to run a larger gap (this would lead to a hotter spark)

Many hotrodders and performance guys use colder plugs because it will help prevent engine knock. I think a colder plug would be great if you want to bump compression.

I've never tried this but I think you could see benefits from using a hotter plug with stock compression.

[redpoint5]

I would think a hotter plug has more insulation, because "hotter" means the engine gets hotter. Spark plug ratings are an indication of how much heat they move away from the engine, so "hotter" should remove less heat from the engine due to more insulation.

Makes sense to me though. Put in plugs that make the engine run hotter, and it should heat up faster and generally dissipate less heat.

[teoman]

I thought it was how far in the plug goes. (But i do not know much).

[arcosine]

all bad tips. dont do it.

[JohnnyJerry]

Redpoint, yes sorry, I put it wrongly. However, it's not about moving heat from the engine, it's about cold/hot firing tip.

Arcosine care to elaborate?

what could go wrong with indexing a sparkplug? Or side gaoing it?

Alot of engines will run just as well with one grade hotter plug. Most engines are specified hotter anyway on generation shifts. Can see anything wrong wtith that as long as eco driving is the primary drive style.

Low Octane might be a little controversial. But most engines will do just fine as long as the engine isn't pushed.

Running low oil is a well known trick among dragracers. The oil woild need to be changed more frequently, but orher than that, there should be no issues running on minimum on the dips tick.

[JohnnyJerry]

Teoman - heres an explanation for Denso plugs:
https://www.sparkplugs.com/Data/uplo...Plug_Chart.jpg

[arcosine]

Taking oil out of an engine is dumb, you'll wreck it. There is a reason for the oil level,
1) Cornering does not expose the oil pump pickup to air! Air is compressible, will trash the hydrodynamic bearings.
2) The oil will wear out faster, contain more contaminates between changes.
3) Oil will be hotter, degrades in Arrhenius relationship.
4) The crankshaft NEVER touches the oil in the pan at proper level anyway. (Unless your driving a Model T Ford with splash lubrication))
5) the only thing your saving is the quart of oil you didn't put in the car - false economy they say.

Hotter spark plugs will not make your car warm up faster, unless you have a fouling problem, hotter plugs will just wear out faster, give problems. Its silly to think a tiny plug could warm a whole engine. This would be good only if the car is driven on short trips where the engine does not reach operating temps.

Low octane fuel will make your car ping or retard the timing, Both bad for economy and engine longevity. High octane will gibe better mpg. This would only work if you are in Mexico and buy the cheap 70 octane fuel and baby the car..