Ran car without coolant

[MarusGTR]

Change your spark plugs to ngk bkr7e gapped to .8 mm. That should fix your stuttering issue after 5k.

Bad advice for RB26. Correct sparkplugs are JIS standard plugs; BCPR6 or 7, E or ES if seasonal, EIX if you want an iridium tip.

BKR are ISO, shorter by 3mm, they damaged my coilpacks this summer while I had a local shortage of BCPRs. It seems first gen RB designs in Skylines were JIS (RB20, RB26) and later went ISO with RB25s.

PS: In NGKs, any plug finishing with E or ES are gapped at 0.8 unless specified by a dash number.

PPS: Well it appears I've contributed to a zombie thread. Great, I feel special.

[collector240sx]

Lol don't worry Marc,

Nobody even seam to have considered that oil also help cool the engine , at least for a while. It's the first thing I would have check.

Also when just Idling there isn't any load on the engine. An engine takes longer to warm up when there's no load on it. You can notice this in extreme cold weather when the car won't warm up unless your moving, and the temperature can even go down if you stop in traffic.

[h4X6]

or in the case of my civic, the opposite... lol i warm up idling and stopped versus driving LOL

[RANTARAVE]

Bad advice for RB26. Correct sparkplugs are JIS standard plugs; BCPR6 or 7, E or ES if seasonal, EIX if you want an iridium tip.

BKR are ISO, shorter by 3mm, they damaged my coilpacks this summer while I had a local shortage of BCPRs. It seems first gen RB designs in Skylines were JIS (RB20, RB26) and later went ISO with RB25s.

PS: In NGKs, any plug finishing with E or ES are gapped at 0.8 unless specified by a dash number.

PPS: Well it appears I've contributed to a zombie thread. Great, I feel special.

BKR7E is like the plug most recommended on GTRC :s how did they damage your coilpacks?

[steveo1502]

I also run bkr7e, had same ones for 4 years, I'll be swapping for same ones

[MarusGTR]

I'm just stating facts. Recommending BKR series, an ISO plug, for RB26 is misinformation. RB26s run JIS plugs. Yes you can run BKRs and most on here do and they work fine, but they're not the plugs suited for the engine.

I'm still running a factory engine, everything is original. The BKRs damaged my original coilpacks because of poor contact from the electrode contact to the coilpack spring; the car had been running JIS plugs in Japan (the original PFRs) and I ran BCPRs over here for durability. I had always in the back of my mind that the spring had probably settled farther up in the boot than when they were new, as heat would have likely changed its neutral point by heat treatment of the metallic structure. Anyway, I still changed for BKRs at the beginning of summer for my yearly service as BCPRs were getting scarce in the region. They were okay in the summer heat, but I started having violent misfires when the weather started to get cool, until the car wasn't drivable, something I hadn't experienced before.

The air was getting too dense and was snuffing out the spark.

So I took the BKRs out and found (literally) the last BCPRs in the province. I was still having a missfire, albeit less violent even if the air was getting even cooler (thus I concluded I was going in the right direction). So I now assumed my coilpacks were at fault, took them apart and started looking in gap between the heatsink/bracket (could be a heatsink?) and the body and noticed they all had scorch marks; the voltage had managed to leak through the boot with the BKRs, and now the short circuit path had remained while I had the right spark plugs on. A coilpack tuneup finally fixed the misfire by sealing the short circuit.

Still, I'm not sure if my power output has been affected. I'll have a more thorough discussion in my build thread... can't say when I'll start though, there's some stuff coming up.

PS: Mind you, I ran two sets of BKRs this summer, so the plugs were new. Also, you can bet all these plugs had all the same gapping.

[RixR32]

^^ My car didn't run right on BKR's either.
Thought I was the only one!!
I was chasing a stutter for a while in the summer after intsalling them, and then hence overlooked the plugs as they were BRAND NEW BKR7E's.
I replaced a whole whack of things that can cause a misfire, including coils. After nothing helping, I put my BCPR6's back in and ran like a champ again immediately.

Not sure the reasoning, but thats how it went down. Stocked up on the BCPRs since :-)

Rick

[MarusGTR]

^^ Good man! The reasoning is simple; with the shorter BKRs the spring has less tension by less displacement, so less positive contact is made, and there's a better chance at leakage. I find it odd people focus on gap and coil power when they don't try to maximize current's path efficiency. Its like trying to adjust a gap for a sparkplug that has its power fed from the equivalent of a dangling wallsocket plug.

You probably could've saved your coils with a tuneup, as I did, but I think they are weak now. I just don't feel the power I used to get before the BKR missfire started.

PS: Some Saab owners are starting to report that they're also having trouble finding BCPRs...