Plug gap advice please

[hks_kansei]

Is there any reason you chose the motorcycle coils rather than car ones?

Perhaps changing to car ones would be simpler, because then you're at least able to use any plugs without worrying about them having a threaded end.

[davekmoore]

OEM coli packs were failing. Figured might as well go to COPS rather than buy replacement OEM which would only fail again down the line. The Fab9 kit I got included motorcycle style coils and high-spec unobtanium plugs of the wrong heat range. Just need to find the right combo, even if it does mean getting plugs made of unobtainium. Hopefully NGK will give me the correct solution soon, and from their standard range, which I'll just swap more often than the unobtanium ones.

[Magpie]

Here is one of my plugs that I use (with COPs). I will get the type and gap details if required.

Spark Plug by Eipeip, on Flickr

[madjak]

You need a dyno to be sure.. But I tell ya what, if you brought it to me id fit BKR7E's, gapped to 0.6mm and I reckon that it would be perfect first go.

x2. Basic plugs are cheap and work best. I also check the plugs from time to time. Each modded engine is a bit diffeent so you don't know if the heat is right until you've tried them. If they show up as too hot or too cold then I just buy another set with the right range. Much more reliable than searching for answers to this on a forum.

How do you tell if a plug is in the correct range? My engine is a pig to start, keeps fueling up the plugs. Once running though it's fine. I also have issues with the Toyota CoPs that if they are bolted down to hard they will misfire. Loosening off the hold down nut corrects the issue.

[manga_blue]

IK22 might be a better heat range for you. Denso 24 is equivalent to NGK 8 I think.

The key words are "solid terminal nut" vs "removable terminal nut". This need not only apply to spark plugs.

[Magpie]

During my motorcycle days (2 stroke road bikes) I always used plug readings to decide on the plug and tune.

If your plugs are fouling it could be the obvious too rich mixture or low speed driving. You could install a hotter plug so that its self cleaning temp range will be reached quicker. However using a hotter plug in a high reving engine could cause detonation.

EGT's can give an indication of what is the normal combustion temps and this will help select the correct plug temp.

I'm happy with the plugs in mine based on the condition (posted pic above)

[manga_blue]

Also in copper as Denso K22PB

[madjak]

I'll just keep doing what I'm doing!... that is carry a spare set of plugs. If I fail to start the car on a cold day and fuel up the plugs then I can switch them out. It starts first fire then.

I have a small window of opportunity to start the car when it's cold. You need to have a correct combination of throttle and holding the starter on whilst firing. Miss that window and the battery starts getting low and the plugs start fueling up. I also have to run it until warm... If I shut it off early then it's hard to start again. It's a combination of high compression, crazy cams and bad cold start settings on the ECU, and probably a battery that's too old.

[Magpie]

The plugs I use are HKS 50003-M40i (NGK #8). The IK24 is an alternate at least that is what google says.

madjak mine starts very easily on E85, no pedal required however on 98 it is a bitch and needs the foot flat to the floor to start.

[rascal]

The plugs I use are HKS 50003-M40i (NGK #8). The IK24 is an alternate at least that is what google says.

madjak mine starts very easily on E85, no pedal required however on 98 it is a bitch and needs the foot flat to the floor to start.

Magpie,
That would make sense. You need ~40% more fuel with e85 so if start is tuned for e85 then when back on 98 it would provide 40% more fuel than needed and flood on starting. Holding your foot flat would engage the fuel cut, and so would reduce the existence of the extra 40% fuel allowing it to fire.

Can you wire in a momentary switch so that you apply a x% reduction in fuel when switch is on, so can start on 98 without all the extra fuel. Then release switch when started and run as per your normal maps (using the flex sensor I imagine)

[NitroDann]

The ecu should be doing all of that and start properly on both fuels.

[Magpie]

Rascal/NitroDann the issue is not that bad, rather it was pointing out that it starts easier on E85 than 98. When it was on 98 only it was just as hard to start so that part has not changed.

[93_Clubman]

Dave, the NGK BCPR7ES is also recommended for the Toyota 4AGE 20V motor, & reading the NGK website last year the BKR series took over from the BCPR series, so not sure if BCPR is going to be phased out. Checked the garage last night, but found only NGK BKR with the fixed top.

[madjak]

I recon mine starts just as badly on e85 and 98... If anything the e85 might be a bit easier as I think the ethanol evaporates quicker so it doesn't wet the plugs as much. I should also note that it's only hard to start when cold, which might be a combination of battery, extra friction from cold oil and cold start settings in the ECU.

I have to be very careful starting when cold as sometimes it backfires bigtime. When I first installed the engine one backfire was so big it skipped a tooth on the timing belt! (not good when your 3 degrees from interference) Now I just keep the starter cranking whilst it fires, which stops the backfiring but it's harder on the battery.

I actually might buy a LiPo and hook it up to an anderson plug in the engine bay for extra amps whilst cranking and starting the engine when cold. Once running I can disconnect it.

Does running Toyota COPs require anything change in plugs or gap? Also how do you tell if a plug is at the wrong temp rating? What should I look for?

[manga_blue]

Somehow people are missing the point here that Dave is looking for plugs with removable terminal nuts.