Halo sparkplugs

[krousdb]

Originally Posted by JanGeo

Well temperature really has a small effect - I just went around my usual Ocean Drive at noon time today 14-20 degrees outside and started cold but got 42.3mpg . . . a few days ago on the 45-50 degree day I got 44.0 and it was windy and raining wet roads daytime . . . so go figure . . .

My Prius is much more sensitive to temperature. In 15-20F weather, I would be lucky to get 55MPG. In 45-50F weather I get 70MPG. About a 27% improvement.

The del Sol does not appear to be quite as sensitive. But I won't know for sure until I get the SuperMID.

[JanGeo]

What I mean by small is all I have to do is goose it for one gear and the mileage for the trip drops a mpg or two for the 12 mile trip even a single red light will affect the result. But the variation on this test route is within a few mpg consistantly so it is nice to see things that we know affect mileage tend to still affect it the way they should.

I asked my brother about the Halo Plugs and he said they are aircraft plugs and thinks they are not that great - only thing that works best is the Champion Gold Platium plugs with their wider heat range and small electrode - everything else is a gimmick . . . of course he thinks it's a bad idea to be putting acetone in the gas too. I guess the only way to tell is to try them - bet they would work great in a Hemi head - indexing the plug is still the next best thing if only I knew where the valves are in this VVT-i motor . . .

[MetroMPG]

i'm avoiding spending time on mods that claim to promote more "complete" combustion based on info on http://fuelsaving.info

The unburnt fuel in the exhaust (even before the cat) represents 1 or 2% at most of the input fuel. If you factor in the energy in the CO emissions, the figure still only rises to 3% maximum. So even if the fuel "saving" device could totally eliminate unburnt fuel and CO in the exhaust, and give an absolutely 100% complete burn, you would only save 3% of fuel. source

i believe this guy knows his stuff - he's a british auto engineer working in the industry with specific experience in engines.

nevertheless, before i read his site, i foolishly went out and bought a set of bosch platinum plugs. replaced an essentially new set of "regular" NGK plugs, and I now seriously doubt there's any difference between the 2 (other than perhaps service life).

[JanGeo]

The Bosch plugs are very good but not quite as good as the Champion - they are the next level quality down and been know to break the insulator portion. But you did ok - the smaller center electrode allows for a higher e-field to build up and thus makes it easier for a spark to form - this is basic e-field theory in electricity. The pointier the electrode the easier the spark jumps - that is why vandegraph generators have big spherical balls so they hold the charge and don't spark as easily. The unburnt fuel is not the issue it is the miss when the fuel does not even ignite that you are going after or the late ignition that makes it studder - even my new xB has a little hesitation once in a while and I am thinking of checking the plugs and indexing them. Also Platinum is a catalyst and even a few molecules of it in the combustion chamber helps burn fuel better - now there is a stretch!

It's more about getting all that there is not getting more than is there - making sure you don't get misfires at full throttle and high or low RPM.

[Bunger]

Originally Posted by MetroMPG

i'm avoiding spending time on mods that claim to promote more "complete" combustion based on info on http://fuelsaving.info

i believe this guy knows his stuff - he's a british auto engineer working in the industry with specific experience in engines.

The fact that there is a maximum of 3% of un-burnt fuel isn't really giving you the full picture of what's going on. If 50% of your combustion was happening in the last 10% of crank rotation before the exhaust valve(s) open, this energy would be almost wasted. The benefit of multi-spark and better (at least advertised) flame propagation is the TIMING of the combustion. This is also why having a good swirl or tumble within the combustion chamber helps promote fuel economy (and power). You want a consistent "controlled" burn, which in theory, these types of plugs should help with.