Unlocking Fuel Economy (Octane preview)
 

Well guys its been a long month, running the two spark plugs thru its paces (NGK Vs. Bosch) its has yielded some pretty interesting results, Some results that I expect will be hotly debated for quite sometime to come.

But one of the biggest convincing indicators of improved fuel economy came from driving with our Bosch and NGK, in our tests; we pitted our two Mazda protege's of the same year and same general mileage multiple times with the swapping of spark plugs on the return trips. So let there be no mistake that these are as raw and un bias as they come.

Since this is just the preview report, I will keep it simple till I finish scanning in all the pay at pump gas receipts of me and my companion.

But the results are shocking... and dispel some of the myths or at least common beliefs of Octane.

All I can say for right now is I would rethink the notion of using 87 regular. And to be honest I would say that I have the Bosch plugs to thank for showing me the error of my ways.

Way back after reading thru some of the posts of poor drivability with bosch +4 platinum plugs, it got me wondering as to why half the people that use them have rough idles. And I came to two conclusions after all this.

1) is to clean your injectors and fuel system with additives, with the bosch plugs the effect can be felt right away after a full tank treatment of the right strong stuff either by Pennzoil or other top brands.

2) It really is the octane.

Other conclusions that were very prominatent in this report are the fact that these Bosch plugs seem to be victim to a slight performance hit on low octane fuel.
Now before we run to the exit and make a final thought and say "Ah HA see bosch sucks" not so fast, that isn't the case at all, and I hate to say it, but under 89* 92* and 94 octane tanks, the bosch plugs seem to beat the NGK iridium under quite a few of our serious tests.

For example one of our test had us take our street machine on the road for a trip to London Ontario and back home again to Toronto.

The two cars were setup the exact same, right down to the K&N air filters, same inflated air pressure tires and same octane fuels. The only thing different in the cars are the spark plugs, one car fitted with Bosch +4 platinum plugs and the other car fitted with the NGK iridium IX plugs. At the end of the first leg of the trip, the cars would be cooled and the spark plugs were switched between cars. Both sets are fairly new and purchased at the same time. The whole point of this exercise is to recreate the same results on the return trip. And to maintain their validity. Are you guys following? lol haha lets continue

The test conditions were to drive in a shadowing formation, to not allow a separation between cars, so pretty much follow the leader. The only debate that we had before we left was what to set the cruise control at. a) if we drive at 95kmph to achieve maximum distance and fuel econ. b) or to set our rides at full after burn and let them ride at 125kmph all the way. We decided on the real world speed of 125, just seem more logical. The results were amazing.

Here is the route taken http://kevante.redirectme.net/drive.jpg

The distance travelled on a full gas tank was 170km. for measuring fuel economy we pretty much refuelled at the london checkpoint, recorded how many Liters were lost from the 55L gas tank, swapped the plugs and did it again on the way home.

Protege #1 fitted with NGK plugs achieved a depletion of 13.51 litres of 92 octane fuel compliments of the Sunoco gas station acrosss the street

Protege #2 fitted with Bosch +4 plugs achieved a depletion of only 12.645 Litres of 92 octane fuel compliments of the Sunoco gas station acrosss the street
*note: we luv Sunoco gas :o

pretty impressive results, the results on lower octane were similar with bosch only slightly beating out the NGK on lower octane, pretty much a dead heat. under 90% highway driving.. But all that with higher fuel consumption levels for both :(

Regardless more will be covered in the review that is soon to come.

cheers

A city driving trip with 80% city driving will follow

For the spark plug head to head test...couple questions:

Is there an elevation difference between the two locations?
Was there a difference in ambient temperatures...such as early morning versus mid day?

elevation is flat relatively

i think i follow you on that question, but we had to balance our reason for driving to london, lol (girls) over ensuring that the envirnment was similar,
the day time morning run and the return trip was at night, we took the 4 bills and calculated the average results and thast what we got,
so we think that that was the best way to ensure that everything is equal and fair.

I'm just playing advocate D. It's interesting information...
Personally I'll take girls over geek stats anyday ;)

but geek stats save you money, so you can pour it into non-returnable resources (a.k.a. girls)

yet another good comparison. I don't want to be a "doubting thomas" but I need to point out that Octane is only a measure of a fuels ability to resist detonation/pre-ignition. It should have nothing to do with mileage and how much fuel is needed to power the vehicle.

By any chance would the car that achieved better mileage be the one in the rear of the caravan? If so it may have been more of a draft-effect gain.

I'm very intrigued by your spark plug threads since I'm going to be running some colder plugs in my supercharger kit but unless you're running FI you won't be able to do the same testing for me.

I guess i didnt put togethe my preivew well, there really isnt a car 1 and 2, the spark plugs were switched, so its rated by plug, the bosch surprisingly achieved a better milage, the reason why i brought up the octane in to this is when I made the switch to the higher grade, in city milage did improve dramaticly over regular grade. we ran it twice to confirm. so one way to look at is, either bosch runs crappy or not so good with low grade, or there is a performance benefit felt by using the recommended higher grade, either way, there was something there in terms of economy,

more on that later for sure :) very interesting though :)

so what is it you were looking into Rod, cold plus, I still think NGK is the way to go :) but the bosch did proved its just as good :)

It's also possible that the trips were in a prevailing wind. If one trip was upwind and one downwind, there's your difference right there.

Omron, I'm going to buy just standard copper plugs one heat range colder for my first run of supercharger testing. I've run standard copper plugs in all of my nitrous cars with much success and was expecting the same with this application. A 4-tip electrode may be better though since it will be forced induction and have more air and fuel to burn up...what are your thoughts?

Vielster, those numbers that i posted are actually the average of the trip out and the return trip, in both cases, the bosch acheived more km per litre, in both cars.

So the playing field was pretty much equal. because both cars were going the same direction at the same time. we were driving side by side most of them on the 3 lane road. hahah no slip stream stunts.

as long as your not running nitrious I think you should be safe, due to the extreme temp. I am not sure the Yittrium would be able to stand up to that kinda of punishment, but if your takin about a super charger I think the 4 tip would eat up that air good :)

I would say go thumbs up, but I would say what is the setup for your rig, is this for just general driving, or high end stuff, I find based on my results, the up power range performance of the bosch plugs are great, but the low end is not so great, so if your using it for top performance, I think the bosch plugs are great for afterburning, the response is good and I now beleive the claim of less missfires, But as I said before, I would use no less then 89 Octane when driving with these plugs, to be honest, its very easy to feel the difference, not sure why you can with the bosch plugs and not NGK , but I would say thats one downside of BOSCH, lowend performance will be normal or %1 sluggish if you know what i mean.. but I would say that htere is a definate response feeling felt by myself and my wingman, comparing it to standard replacment plugs, the high end I would score better, and as the fuel tests are showing me, they even edge out the NGK.

After all these tests in the field and driving, I am sure that the Bosch plugs will edge out the NGKs, we are thinkin maybe the IX is the wrong choice, is there a slightly better NGK irridium plug?

Rod, One aditional thing to make note of, one thing i didn;t know till I called bosch is, there are different types of 4 tip plugs from bosch,

Surprisingly they have a Silver core one and a Copper/Nickel plug as well, For nitrious setups I would go with these, look into it here

http://www.boschautoparts.co.uk/pcPlug4.asp?c=2&d=1

Here here is information on that Yttrium, from my understanding, I beleive that the platinum/Yttrium plug should be able to handle it, but I will say, take the UK version of the plugs that don't have platinum in it and uses Nickel.... Read on :)

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The main benefits from using Yttrium in our Super Plus Spark Plugs


It forms an adhesive oxide layer that makes the spark plug extremely effective in minimising wear


It maximises the spark plugs protection against the high temperatures created


Yttrium molecules are positioned between the chrome-nickel molecules, preventing them from melting 'melting together'. The result being that the substance loss from the centre electrode throughout the spark plug's service life is minimal.

As the centre electrode erosion is minimal, the ideal electrode gap is maintained throughout the service life of the Super Plus spark plug. This allows cover of several spark plug types (i.e. with different electrode gaps) by only one Super Plus spark plug, with its factory pre-set electrode gap.

I was looking around (I use the Bosch bypass valves in the supercharger kit) and I didn't see anything in those descriptions about using which plug on forced induction.

Rod, this plug from what I understand it what your lookin for, thats from bosch, when I asked about Nitrous, forced induction should be fine for all metal types. its just the nitrous you have to becareful of,

the way platnium unbonds or undones itself with other alloys is the weakness under extreme temp.

http://www.boschautoparts.co.uk/pcPlug5.asp?c=2&d=1

But you would have to order it from the UK or Aus for the silver

so you think I should test a set of "silver's" in the plus4 style? These aren't available here in the states? I'm planning on including plugs in the kit also once I feel good about the plug I'm using.

if you call Bosch, it may be possible to locate a pair, but you can also inquire about the heat tolerences about the AMerican version which uses Platinum core, to be honest with you, I think these ones should be fine, because the 4 prongs are composed of a Yittrium/Nickel alloy, which by my understand of science should prove stable and safe at high operating temps. only if the platinum is in a alloy form will the bonds be unstable leaving it pron to buckling and breakin, the core is pure Platinum and from what i understand the plug is of a proper heat range to withstand extreme temps.

:)

Rock on dude. :)

An Alternative Plug -
 

I just this AM installed a set of Denso Iridium Power plugs in my '02 Pro LX, NA, minimum mods. I went from an apparent original set of NGK copper plugs (BKR5E) @ 33K miles to the Auto Zone supplied Iridium plugs. Made sure the set was at .040" gap & installed. Did NOT reset the ECU, and had no trouble. Let it warm up, and headed southbound. The idle is between 500 & 600 rpm, and purrs like a kitten! The pickup is exceptional, and the throttle response is fantastic!

According to the manufacturer's hype, it is supposed to improve acceleration (!), burn hotter, and deliver improved fuel economy. I will track that and post improvements or lack thereof.

We may have a winner here, Ladies & Gentlemen!

The difference you're probably noticing is just due to switching from old, used plugs to new plugs. It is improbably that a plug would give you any truely noticeable power changes. The temperature of the burn may improve fuel economy by providing more complete combustion, but would only possibly give less than 1HP change, if any. Just hope that the plugs don't cause any problems because of their hotter running temp.

Based on my half-hour run yesterday, I noticed no increase in temperature in the run. I am keeping a close eye on this. More to follow.

vielster is right - the biggest shift is from getting the old plugs out. If the performance stays strong right through 30K miles - then i would declare a superior plug.

Factor additonal cost of 'good' plugs vs just swapping out the $.99 cheapos at a greater rate (beacuse it is sooo easy :) ) say at 20K miles...

VS.

Any verified improved fuel economy (X cost of fuel/gal. times period of study i.e. 30K miles)

Bottom line: I don't expect any big advantage - so do whatever is best for you.

Interesting thread throughout. FWIW, I pulled the stock plugs on my 03.5 P5 about 1500K ago (15,800K) and dropped in a set of Denso iridium IK16s--roughly 2 heat ranges colder than the NGKs that came with the car. The majority of my driving--about 85%--is 75-80+ and my colder plug choice was based on my experience with other 4-bangers of similar layout and output, and nearly identical driving patterns. BTW, plug checks show no abnormal burn patterns when cut clean under power.

While mileage formerly was in the 29+ range, it's been high 30s-31+ consistently since the changeover. Idle, throttle response and butt dyno "power" seem little affected, but the engine feels smoother when pushed to 6500+ under WOT, a strictly subjective opinion. The "fresh plug" argument is recognized and taken into consideration.

Having seen a number of arguments pro/con re: iridiums vs. copper, and in particular, the NGK "V" groove extended tips, I put a set of the latter in my wife's '03.5 ES with virtually the same mileage. She sees little change in overall mpg, with about 60% of her driving in town vs. highway.

Omron noted that the Bosch platinums provided improved mileage at road speeds, while in the suburban setting--around town--any increase in mileage was much less remarkable. This is consistent with the typical internal combustion engine under stop and start conditions as opposed to constant road speeds.

While the Bosch plugs in Omron's comparo suggest notable performance and mileage gains, I have found them ultimately to not perform well for me in three different modified engines, all of which were twin-cam fours burning premium fuel. This is not to say the Bosch platinum is not a quality plug; merely that I reverted to NGK in all instances when Bosch platinums failed to meet my performance expectations.

I'm pleased with the Densos and may drop a set into the ES for a comparo with the NGKs now in the car. If the mileage increases, based on the same driving patterns and habits, I can most definitely recommend the iridiums, which I'm inclined to do at this point.

Of course, I haven't tried the Bosch platinums in the P5 or the ES, but then, I would probably have to burn 89 or 91 octane fuel if I wanted to fully recreate Omron's tests. I currently burn 87 octane since I'm at 5280 feet, which drops the effective CR nearly a full point and allows the use of less expensive fuels without problems. I would find the expense of higher octane gas, as recommended by Omron, to be a "pay your money and take your choice" option that I'm not disposed to try.

*Why* would i run the higher octane/more $$$ ($$CAD ;)) to save a small ($) fuel amount?

If the timing would advance to take advantage of the Bosch plugs - yeah! I would do it!

Does filling with 94 octane and then clearing the ECU (disconnect and dance on the brake) give me a noticable jump in power? Does the ECU run a more advanced timing because the knocking doesn't occur when it did before?

Oh Boy!Oh Boy!Oh Boy!Oh Boy!Oh Boy!

a key factor i didnt see in your description is which car was the lead car. your description indicated to me that the ngk car was always in front, and the bosch in the back. this would give the car in the back an advantage due to drafting, and would show an increase in milage. Nullifying all your findings.

if i am wrong please correct me, but you did not make it explicitly clear.

he said this:

So the playing field was pretty much equal. because both cars were going the same direction at the same time. we were driving side by side most of them on the 3 lane road. hahah no slip stream stunts.

I am not sure what the Computer (ECU) protocols are, nore could i explain what exactly is giving off this effect but it seems to only last for 10 km or so, but if you have a Sunoco near you and you can try it for a little while do it. The harm to your engine is minimal but if you feel the car is Knocking cut it out. The timings may run more advanced or it may be something else, Its only something we notice or felt in the driving. We are waiting on a computer interface unit to hook up to the ECU to monitor these values. Then we can see for sure whats going on.

Cheers

Thank you Phantom for the quote, haha I thought I said that in there somewhere when I was reading the question...

it was pretty much side by side driving most of the way. I think the closest we ever got to each other was 25 meters and that was when the highway for the last 30km turned into a 2 lane road. We didn't want todo the side by side thing cause those damn mack trucks were starting to hit us with a bit of that highbeam rage.

We are going to do another trial to meet up with those girls in london again so we are going to try it again, both plugs have now 12,000 km on them, which is a good breaking in for both. I think with my friends car running the NGKs with slightly less km on them. But after a visual inspection, we will proceed.

Well put Gino, and very true, my only reason for using Sunoco is my wonderful discount card for higher octane grades. I wouldn't expect the average man to start shelling out dollars at the pump just for a grade of gas that slightly has a less amount of crap like sulfer in it. I mean a 10 cent a litre adds up quickly. But since it was an offical test I did want to go with what the manual says.

And the for future of my tests 91 or higher will be the standard for all my tests, Straight from Sunoco :)

The schedual dyno tests in the near future will settle everything, but I am getting alot of people asking me if the IX irridium was the best choice is there another NGK irridum plug out there that I should think about including?

Re: Denso Iridium Plugs
 

At Longgggg last I'm back on with an update of the earlier comments on the 0.4 Denso Iridium plugs. I made a 6,000-plus mile trip of the US (even came through B'ham, Matty!). My mileage was not much better than running copper plugs. On the wide open interstates I DID push the speed up to 115, put had to bring it back down due to the trucks on the road. And it did feel like there was more to give! My original comments of better acceleration, etc. Was based on the old plug/new plug switch. Highest mileage was 30 mpg, worst was 24, average was 26. So much for grand and glorious raves about iridium plugs.