I've been sifting through threads for too long now (at work) and have not found any definitive suggestions regarding colder plugs. I have seen some threads that suggest precious metal plugs are not ideal for forced induction cars, particularly if boost has been increased, ala pulley reduction.

My question is, should I just go with a colder range (1 or two colder) copper replacement of the same brand? NGK is what I believe the MCS has from the factory. Other suggestions? I'm in southern SC where it will be hot for a while yet.

No ignition mods thus far. Going to the track beginning of September.

Thanks.

 

I got the DEnso iridium and i'm very happy with them. I also have the pulley and sims to work with it.

You can ask Mini-madness.com

 

Thanks. That was one plug I was interested in hearing about but I think Iridium plugs would be considered precious metal plus they are 17 bucks a plug.

 

I ordered the DENSO's last night, along with some Magnecor 8.5s...

The DENSO Iridium IK20 is the one to get, supposedly. At least that is what I ordered. Going up one notch higher would be colder. So, for DENSO, that would the be the IK22 - the next coldest.

I didn't get this one as they state that this should be done for heavily moded engines. Their definiton was a 75-100 hp increase. Being that I'm in the 200 to 210 range, by guesstimating, I got the IK20's. They come pre-gapped at .044. They should be .032...

 

>>Thanks. That was one plug I was interested in hearing about but I think Iridium plugs would be considered precious metal plus they are 17 bucks a plug.

Congrats on your 100th post!

Try these guys out:

http://www.cartunerz.com/cart.asp?productID=80004

Also, free shipping...

 

I would recommend, the ngk bkr7equip if you are using factory ignition, it is the same plug they are using with the jcw kit, if you are using a aftermarket ignition, either use the iridium or copper plug, as far as a copper plug i am running Autolite Ar3932 race plug, but i am also runing MSD, the iridiums earlier suggested is also a great plug...

 

Hey,
Pilo Racing has just finished it's testing on a total Ignition upgrade with the option of a colder range plug for reduced pulley. We have increased the voltage of the coil from about 32,000 volts up to around 40,000 volts, replaced the wires with 8.5mm silicon wraped wires, and race designed spark plugs gapped to .065. This package has smothed out the idle, given an increas in power in the low end, as well as better gas milage on the highway. This package will be sold for under 200 and should be available by early next week. Check out http://www.thepilo.com later on this week for more details.

 

At which point of modification do colder plugs become beneficial?

AND

Isn't the bone-stock cooper s already running on the hot side? ...almost enough to warrant a colder plug?

I'm asking becase a while back there were several threads regarding A/F & the cooper s. It was documented that the ECU was advancing the timing and running the engine rich (10:1) @ high rpm. A corresponding dip in power was also doccumented.

The theory behind the rich ratio was that the additional fuel cooled the combustion chamber - preventing pre-ignition / leaning-out (detonation).

So... if one were to use a colder spark plug (draws more heat out of the combustion chamber) would the ECU compensate for the cooler combustion chamber by leaning out the A/F and or retarding the timing?

Opinions? Randy? others?

 

Good morning all,

This thread on spark plugs is important and I want to make a couple of comments. Those of you who are interested in more information along these lines, will find postings under "spark plugs" in the Search function that have addressed many of these same issues. Reading them may help.

The concerns about proper spark plugs are warrented in that we all want to try and get the most from our beautiful MINIs. However, there is a lot of confusing information and "urban myth" about ignition systems and spark plugs in particular that make understanding these components difficult.

A colder spark plug, such as the JCW BKR7......, (expensive as they are) is probably a good idea for any MINI in any stage of tune. Don't expect a detectable increase in dyno power. But one can expect that the engine management knock sensor will likely receive fewer knock inputs and that the power available in certain high load and high temperature operating conditions will be more dependably available. And, the longivity of your valves and spart plugs might be a little bit better. Rules of thumb that try and match one engine HP level to some particular spark plug heat range are simply not true and confusing. The important variables in heat range selection are boost pressure, how often one is using the upper RPM (upper power ranges), load on the engine, and inlet air temperatures, to name a few. A loose correlation with HP levels, and more reflective of environmental and operating conditions.

The choice of spark plugs, nickel-iron, precious metal/iridium is not important from the power perspective. The choice of spark plugs is primarily relevant from the perspective of spark plug life and small, but potentially important, differences in voltage requirements. The precious metal spark plugs can last a long, long time due to the effects of lower rates of electrode erosion and a lower spark plug voltage requirement. The lower voltage requirement and the resistance to electrode erosion
together add up to provide dependable performance and long service life. A big plus for the average MINI enthusiast.

Spark plug gap is very important for emissions, and low speed performance. High speed performance is less sensitive to plug gap unless the gap is too large and the ignition "system" (system= coil, spark generator, wires, plugs) cannot reliably fire the spark plug and one sees power loss. Minipilo's postings about his ignition system and it's impact on his engine performance fit neatly with ignition theory and a century of experience. The stock BKR6.... spark plugs have an approximate air gap of 0.060". BMW does this for a reason. The MSD ignition coil and the Minipilo system offer an approximately 10% increased voltage output that will allow somewhat increased spark plug gap in precious metal spark plugs and permit small improvements in driveability. All to the good and will increase driving pleasure, but not increase raw HP. Sign me up.

The bottom line is if you want to do something good for you MINI, and love spirited driving, by all means install the one heat range colder BKR7... or the IK-22 spark plugs. Keep the gap at about 0.060". In the dead of Winter and if you are condemned to a lot of stop and go driving, (ugh!), keep using the stock spark plugs until Summer.

John Petrich in Seattle

 

Hi John. Hey, thank you for the plentiful information. I was leaning toward the IK22's, and just changed my order Much appreciated!

Are you saying to gap them at .060? For the IK20's, I was told to do so at .032. If you have some time, clarification and reasoning would be most welcome. Thanks again!

 

Read most of those threads but didn't find anything definitive for a stock ignition, pulley upgrade. You state in your threads that you are running MSD ignition.

I was told the IK20s were a colder range than stock and that the next colder range should be used for a 75-100hp increase.

I haven't read about setting the gap that big. I don't mean to sound doubtful. I do appreciate your long response but could someone else chime in on this thought?

I've got IK20s on the way. Should I return them and go with IK22s?

_________________
'02 Pure Silver/Black MCS, MINI-Madness intake, MINI-Motorsport air box mod, air box mod intake scoops, Alta Pulley, black bonnett/boot stripes, black aero grill, smoked tail lights, 215/45/16 Falken Azenis.

 

Through some confusion, I have both the IK20's and the IK22's coming from the same vendor. One set will get sent back. I'm leaning toward keeping the 22's, as I will be adding still a few more mods, so a colder plug might be desirable. And maybe with the 91 octane CA gas, that should also be a factor in the decision. Any commentary would be appreciated.

 

Found the cross reference of NGKs on the DENSO site. IK22 is only one colder. Changed my order from IK20s to IK22s.

Now will figure out gap.

 

I have the IK20's from Denso, and they are gapped to the factory spec of .032.

While I believe our freind IS informed, I think he's got some numbers wrong. THAT or everyone I've ever corresponded with previously had mis-information.

I think the larger .060 gap is specific to the MSD ignition system set up. That's the only place I've heard about it.

This brings up an interesting point... If stock is .032, and MSD modded is .060 that's an increase of 87.5%! So... are we to interpret that the MSD ignition is 87.5% more efficient or effective?

This just doesn't seem right. ...Certainly not if its only "10% increased voltage"

 

There are a couple reasons that MSD would want a larger gap. If they are expecting people to be using different plugs, since the mini is a 4 prong plug, and most aftermarket are single prong plugs, even with a larger gap sze, you are going to get a more concentrated Spark. Aiding in the consumption of fuel. Also with the MSD, or any other Higher Voltage Coil, and Better Plugs and Wires, the efficiency will be increased because of the less restrictive flow of currect to the spark plug, and better conducting materials at the electrode.

The Pilo Racing System is recomended to run at a gap of .065 with the race spark plugs that are included with the kit. These spark plugs are a U Groove Electrode to help concentrate the spark, to allow for better consumption of fuel

Hope that this answers some questions.

You can see the pilo Racing Ignition upgrade at http://www.thepilo.com

Thanks
Dan
Pilo Racing

 

There is a lot of mis information on this thread. Opening up the gap makes the spark traverse a larger distance from the prong to the electrode. This is hardly a more concentrated spark. It would actually be a weaker spark, if all other things are held constant. The idea is that the bigger spark is more exposed to the Air/Fuel Mix that has filled the cylinder, allowing for more complete combustion and more power.

This is sometimes beneficial when you have a ugly CC where the plug is shrouded or your mix isnt uniform and its hard to light the mix. I've never heard of that being a problem on this engine, but I look forward to your testing.

 

>> A colder spark plug, such as the JCW BKR7......, (expensive as they are) is probably a good idea for any MINI in any stage of tune.

As some of you know, I've been having pinging issues with my EvoTech ECU and pulleyed MCS. Randy told me to go wiht a plug one range colder, and I spent the better part of yesterday calling around, trying to find this NGK BKR7EQUP, or equivalent, but came up empty handed. Yes, my stock plug (which looks very clean and is not burned), is the NGK BKR6EQUP. Kohlweiss, NAPA, Kragen, speed shops, Mtn View MINI, etc. etc. couldn't even find a cross reference for this plug in another brand. They said that Denso didn't even make one that cross referenced. I don't know who to believe.

I finallly called NGK in So. Cal directly. They told me that there is no four electrode equivalent to our stock plug. The plug they recommended I use is the NGK BLR7EKU, which is one range colder than stock. However, it only has two conductors, and not four. Since I'm going to the track tomorrow, and I need something today, I ordered 10, the minimum order but at least they're only $7 each, and they are supposed to arrive this morning.

I hope this plug works OK. I wish one of the stores had told me about the IK 20 or IK 22. Are these plugs stocked locally anywhere in the SF Bay Area TonyB? I just checked the Denso site after reading this thread, and it looks like I should buy the IK22s. I'll see if the place I just ordered the NGKs from would let me buy the Denso's instead (if they stock them!)

_________________
'03 MCS, EB/B, pkgs#1,2,3, Nav, H/K, PDC, Anthracite w/blk leather, Alta pulley, Evotech ECU, Anthracite SSR Comps

 

>>I hope this plug works OK. I wish one of the stores had told me about the IK 20 or IK 22. Are these plugs stocked locally anywhere in the SF Bay Area TonyB? I just checked the Denso site after reading this thread, and it looks like I should buy the IK22s. I'll see if the place I just ordered the NGKs from would let me buy the Denso's instead (if they stock them!)

Through some confusion, I have both the IK20 and the IK22's coming to my home. I should get the 20's today. After some discussion, and several PM's (thanks everyone!), I will however roll with the 22's. Since I will have a re-stocking fee, I will try to sell the unopenned IK20's...

You can get them online and to your doorstep in 2-3 days for 49 bucks total. I provided the link in the other like thread in this forum.

 

Thanks Petrich! In my Corvair days the rule was to run the hottest plug you could get away with. I would only switch (or have an issue with the current plug) when my engine knock became a problem. Whatever the plug was that we used we only incresed the gap once we improved the ignition system. On a turbo we had but wanted to keep the stock carb which was crap compared to the webber, we could never get the all the knock out and we did not want to retard any more timing. We had the coolest plug AC42ff but it took water injection to make up for the poor gas that is currently available. Unless knock is a problem, and your plugs are within their life cycle there is not a lot to gain. If you live in a large city or near the central US the fuel you use may have more to do with the problem so take that in consideration when you are going to spend a lot of $ increasing pressure.

 

Very interesting input. Thanks to MiniPilo and Zappa for reporting their experiences.

The website Sparkplugs.com is a source of excellent information that will help anyone understand spark plugs and all the variables associated with their use. This website has at least 3 portals that I have found useful, and I'd like to explain each one and how they have helped me.

Portal #1 is in the upper left hand corner of the main page and is titled "cross-reference SEARCH". This portal is like the traditional crossreference manual at the parts store. One can search for your plug of choice, any crossreference and type (platinum, iridium, etc), and see a detailed photo of the plug with the plugs important dimensions. Enter the stock MINI plug part number, BKR 6e, and follow the cross-reference selections and you will see the Iridium IK-20 come on screen with a photo. Neat! NOTE: most auto parts stores, like NAPA, list and order spark plugs by the manufacturer's "stock number", not by the spark plug "part number". So, for the IK-20 the "stock number" is 5304 and the "part number" is IK-20. Why they do this, I don't know. A source of frustration to customers, for sure.

Portal #2 is left of center on the lowest segment of the main page and is titled "spark plug 411". This portal has some general FAQ's and a ton, repeat "a ton" of manufacturer's data on heat range numbering systems, different electrode types, (like the "U" groove electrodes from Accel that MiniPilo will be selling). An overwhelming amount of good data. Lots of fun here.

Portal #3 is right of center on the lowest segment of the main page and is titled "Advanced tuners.....data". This portal offers a mother lode of FAQ's for the performance minded. These FAQ's address all the questions that we have been raised on this forum: plug gap, supercharged and turbocharged engines, Iridium plugs and gap, advanced ignition systems, etc. There is a cool search function for custom engine installations, where you can enter the physical dimensions of the spark plug you need and the search engine will list all the different heat range and construction possibilities that are currently being manufactured. This process is what Zappa was describing in his post about his search for spark plugs to help control detonation in his Turbo Corvair.

Hope that people find this website as useful as I have.

I see that MiniPilo is recommending a 0.065" spark plug gap for his ignition package. This gap is about the same as the gap in the stock BKR6...plugs that come installed in MINI. Good solid reasoning.

Happy motoring,

John Petrich in Seattle

 

Recent driving conditions in the PNW have motivated me to post a follow up on using colder spark plugs in the MCS. My engine is pully'd and I have installed the MSD DIS-2 ignition.

Have been using the Denso Iridium IK-24 plug, gapped at the usual 0.060+", for a couple of months. The IK-24 is two (2) heat ranges colder than the stock IK-20 plug and one heat range colder than the IK-22 plug that some people have started using. Have been experimenting with colder plugs in an effort to "see what works" and in an effort to avoid triggering the knock sensor and upsetting my ECU. The driving conditions have been cool and wet and we are having a lot of road construction in my area. All too often I drive in stop and go slow traffic. Ugh!

I have no evidence of misfire and spark plug fouling while driving. Period. I don't have any yo-yo or hesitation, but I don't know why. Never had it to the best of my memory. Visual inspection of the plugs shows the same white center insulator that I have come to expect with the stock plugs, with only the slightest trace of a brown coloring near the electrode end. It seems that these colder plugs are doing the job. I attribute the apparent lack of fouling to the superb engine tolerances and engine management of the MCS.

Cannot expect any tangible HP gain from a spark plug swap such as this. Would anticipate that the colder heat range plugs would add a margin of safety when it comes to reducing the risk of pre-ignition (knock) and would contribute to consistent engine performance when the knock sensor isn't triggered. The down side of these colder plugs is the risk of fouling.

These spark plugs are available from http://www.sparkplugs.com IK-22 is order # 5310, IK-24 is order # 5311, and, an even colder, IK-27 is order # 5312.

I'm interested in other people's experiences with colder spark plugs.

John Petrich in Seattle