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Sun Aug 17, 2008 12:23 pm

Bought the CB Mini D wedge port heads. Calls to use 12mm long reach plugs. Never had a set of heads for these plugs. What is a plug number to use for street driving?

2332
44's
125 cam
009 dist w/Pertronic
8.75:1 cr

Engine is brand new.

Sun Aug 17, 2008 12:43 pm

I run DR9EA NGk's, but it's a turbo.You can use 7's or 8's

Sun Aug 17, 2008 1:01 pm

you run those to keep the heat down, right?

Mon Aug 18, 2008 4:20 am

The Noof wrote: I run DR9EA NGk's, but it's a turbo.You can use 7's or 8's
Noof, do yourself a favor and pitch those spark power robbing resistor plugs in the trash and get a set of non-resistor NGK D9EA spark plugs instead. With a Turbo you want all of the spark power that you can get.

Tbirdusa wrote: you run those to keep the heat down, right?
You select the heat range of the spark plug so that the spark plug insulator around the tip of the center electrode it is just hot enough to keep clean.

Engine combinations vary dramatically and what works for your engine may not be right for the next person's engine. You need to some trial and error testing and do plug readings to determine if your heat range is correct.

It's always safer to start with a colder heat range spark plug. Assuming that your engine is in good condition, and your fuel mixture and ignition timing are correct, if your spark plug begins to foul, the heat range is too cold. Try one heat range hotter. If the plugs stay clan, you're golden

If you run a high energy electronic ignition system, you can usually use at least one heat range colder spark plug and still have the spark plug stay clean. Using a colder heat range spark plug reduces the possibility of pre-ignition and run on.

A higher compression engine is more likely to heat the spark plugs hotter, so it might be a good idea to start with a colder non-resistor spark plug such as an NGK D8EA. If the spark plug fouls, you can either install a high energy ignition system which will keep your spark plugs clean and improve your performance as well, or you can change to the next hotter heat range spark plug, which would be a D7EA. With a weak Bosch Blue ignition coil you may even need to go as hot as a D6EA. The D5EA is the stock heat range, and probably too hot for your higher compression ratio engine.

With a non-turbo application you might be able to use projected core spark plugs for improved performance. The numbers would be NGK DP5EA-9, DP6EA-9, DP7EA-9, DP8EA-9, DP7EA-9. The -9 indicates the spark plug gap that it comes with in mm.

Scott Novak

Wed Jul 25, 2012 11:22 am

This was the closest post to my question so I thought I would ask here.

I can't seem to find any D5EA spark plugs anywhere. I even called NGK and he couldn't find them either. Does anyone know of a correct replacement. I currently have D7EA in the engine and it just isn't right. The plugs foul sometimes and it runs rough at speed. I was able to locate D6EA but really want to try the stock heat range plugs. The engine has few mods and I doubt the compression is much higher if any than stock.

What years if any used the 12mm spark plugs? These are aftermarket heads and so searching by vehicle doesn't even come close.

Wed Jul 25, 2012 11:46 am

With all the great descriptions of just two vendors it seems the right place to look is all someone needs.......

http://www.cbperformance.com/catalog.asp?ProductID=1278
http://vwparts.aircooled.net/VW-Spark-Plugs-s/65.htm

Wed Jul 25, 2012 12:50 pm

Aircooled doesn't have the 5 heat range. Closest I saw there was a 6 heat range.

They only have the 5 for the 14mm thread. I need the 5 range in 12mm.

I will check CB Performance as well but I am betting the same.

Wed Jul 25, 2012 12:58 pm

Animal78 wrote: Aircooled doesn't have the 5 heat range. Closest I saw there was a 6 heat range.

They only have the 5 for the 14mm thread. I need the 5 range in 12mm.

I will check CB Performance as well but I am betting the same.
You should not need anythjing hotter than a D6EA in a long reach plug unless you live in Alask in the winter and probably not even then. Start looking at other issues after trying the D6EA id you still have a problem and gap them according to application and ignition parts used.

Wed Jul 25, 2012 1:30 pm

That would suck... Living in Alaska.. You know.. Alaska is a pretty broad example.. SE Alaska is warm and wet like seattle (wetter than seattle) while anchorage is actually pretty nice year around, not too cold in the winter either lots of snow. Fairbanks is super cold during the winter. Then there's nome and barrow where it pretty much sucks all the time. :wink:

I have NGK B5ES (long reach though). Also live in Alaska :lol: I can't remember what I was running before the head swap though. Was just the normal NGK plug napa sold for bugs though..

Good luck!

Wed Jul 25, 2012 1:38 pm

If you cant find the d5ea you could try dp5ea which is a projected tip or dpr5ea which is a resister plug they both will work!

Wed Jul 25, 2012 1:39 pm

Double post! Sorry

Wed Jul 25, 2012 2:50 pm

Quote: That would suck... Living in Alaska.. You know.. Alaska is a pretty broad example..
Haines Alaska is one of my favorite places :D

Your local Honda/ japanese motorcycle shop will carry them as well, thats where i get mine .

Wed Jul 25, 2012 3:10 pm

gprudenciop, your listing part numbers for a 14mm plug.

Those won't do. I went with a D6EA plug. It's really the only thing I could find. I am sure the D5EA would have worked but it's just not available. The climate outside really has very little to do with your engine once warmed up. I guess if you just couldn't get the oil temp up then you would have issues. Combustion temps are high and should stay up unless you have some problems. The temp in the chamber is controlled more by timing fuel/air and compression. The typical way is to have a hotter plug for a low compression engine and as the ratio goes up the plug should get colder as the internal temps rise due to the compression increase. You get the idea.

Wed Jul 25, 2012 3:50 pm

I buy my spark plugs at FLAPS or at motorcycle shops, if you're looking for a more convenient option.

I currently use D8EA at 10.5:1 CR and live in Canada where it gets pretty cold...no issues so far, but I've only tried the D7EA and D8EA.

Wed Jul 25, 2012 4:29 pm

I had D7EA plugs and they were too cold. Swapped in the D6EA and it runs better now. I think the idle would improve slightly with the D5EA. I have been dealing with 1 and 3 just not firing very well for sometime. Right now it runs the best it has since I got it. The cruise rpm range is smooth like butter now. It took a combination of efforts to get it this way. Lot's of trial and error. I figure that the best I am going to do with the 34ICT kit and this engine. The only thing I have left to do now is go ahead and go up one more step on the main jets. I went from 130 to 135 but I am thinking the sweet spot is somewhere between 135 and 140. The idle jets might be able to go down one step from 60 to 55 when I do that. Although right now the mixture adjustments are pretty touchy so I will wait till I add the 140 mains to decide that. I am probably just too picky a person to own this car LOL.

Wed Jul 25, 2012 9:20 pm

Animal78 wrote: gprudenciop, your listing part numbers for a 14mm plug.

Those won't do. I went with a D6EA plug. It's really the only thing I could find. I am sure the D5EA would have worked but it's just not available. The climate outside really has very little to do with your engine once warmed up. I guess if you just couldn't get the oil temp up then you would have issues. Combustion temps are high and should stay up unless you have some problems. The temp in the chamber is controlled more by timing fuel/air and compression. The typical way is to have a hotter plug for a low compression engine and as the ratio goes up the plug should get colder as the internal temps rise due to the compression increase. You get the idea.
Yes sorry b is for 14 mill i meant to type d but had a brain fart! I had some d7ea's but kept fouling i switched to dpr7ea and i stopped fouling plugs!

Wed Jul 25, 2012 9:49 pm

NGK does not show that they make a D5EA spark plug http://www.ngksparkplugs.com/pdf/StocktoPart11x17.pdf

Wed Jul 25, 2012 10:38 pm

W1K1 wrote: Quote: That would suck... Living in Alaska.. You know.. Alaska is a pretty broad example..
Haines Alaska is one of my favorite places :D

Your local Honda/ japanese motorcycle shop will carry them as well, thats where i get mine .

I went salmon fishing in Haines a few times when we lived in Whitehorse And I've been to Fairbanks in January. I love the Far North and miss it a lot.

I also buy my plugs at the local bike/sled shop.

brad

Thu Jul 26, 2012 5:17 am

Well I called them yesterday and yes they do not make that plug but I have seen it mentioned several times. So either at some point they did make it or there was something equal to it. The D6EA plugs do seem to work well though. It was a big difference from the D7EA plugs.