Coilpack (??) problem?

[Kinkstaah]

Coilpack (??) problem?

Hi folks.

So it looks like I have misfires in some odd scenarios.
I have a RB28 with Splitfires (it is a RB25det neo stroker)

It seems anywhere over about 12psi I get wild spark breakdown, as in car is undrivable, feels like hitting a rev limiter breakdown.
Under 12psi, was fine. Did a track day on it at 12psi, had fun.

My other spark plugs, below:

 

I can run 18.5 psi on them, which is what I've run on the Dyno. I wanted to try and run 20 on the dyno but the car was not happy (breaking down, misfires)
I got around the problem in the past by adding more timing... but that ended up quite poorly...

So I thought I'd try the ever faithful BCPR7ES, with the aim of running over 20psi!.... but this resulted in no fun times over 12psi.

I would think by this that my coils (which run quite a lot of dwell!) are beginning to fail/get old.
I have had splitfires for almost 10 years now.
I'm well aware of OEM coils only lasting a similar amount of time before they need to be replaced.

Car does not have "a" bad misfire, it's not one cylinder, it very much feels like almost all of them when it happens.
It doesn't happen under idle, and driving the car hard on 12psi with the BCPR7ES's is fine.

Am I on the right track here or are there other things I am missing/could check?

The car makes about 360 (?) KW or so at the moment, running 18psi with the plugs pictured above.

[-S-]

I had almost the same issue. I thought swapping to the trusty bcpr7es will fix but no. My car prefers the expensive iridium. .. (don't ask me why.i did a lot of back to back testing. look for 1 of my post) but the plan in the future is to get splitfires and retry the copper plugs... im thinking tired coil packs. .btw I don't suffer misfire using iridium though just wondering why using coppers i misfire that's all. .

[Kinkstaah]

Given how the iridiums look, it seems they would be better at not being blown out, but I wouldn't think spark blowout is a thing with such a well known sparkplug and well known/'standard' power, and 18psi is not exactly extreme.

They have run 2.9ms dwell for a while - but I never had this issue before, so I am inexperienced when coilpacks start to go. Can't think of what else it would be, the difference is monstrous in power.

Just curious if others had seen this, before I spend another $600 testing. Or $900 if I want new OEM packs, or somewhere in between for a Yaris kit.

[-S-]

Try the electric tape fix too... fixed my misfires. ..

[admS15]

The splits are definitely getting on at 10 years. It would be good if you could borrow a known good set off someone for a quick test. I'd offer you mine but pretty sure the 33 S2 are different from the neo ones.

 

 

[Dose Pipe Sutututu]

Run more dwell till they melt LOL.

Mine is at 3.5ms in the midrange tapering down to about 2.2ms up top

No misfires these days 

[Kinkstaah]

I did try and drop the dwell when I put the BCPR7ES's in.

However that was down to 2.5ms, they have previously been running all this while at 2.9ms constant. The misfires were worse at 2.5 than they were at 2.9 so I changed it back.

All of this is making me think these Splitfires have done well and had a good innings so far but may be due for retirement.

[tridentt150v]

Oddball, but how good is your battery??/ Not contributing to a weaker spark at all is it?

[vxsr33]

I was having a misfire last year so i took apart my splitfires, cleaned them thoroughly with soapy water and a toothbrush, sprayed them with elec contact cleaner, and put dielectric grease where the plugs go in.

Haven't had a misfire since, might be worth a try

[inmaniac]

51 minutes ago, tridentt150v said:

Oddball, but how good is your battery??/ Not contributing to a weaker spark at all is it?

A battery wouldn't contribute to this. Alternator and related system might though, but I doubt it.

[tridentt150v]

That was my point, and the next question.  But its easier to measure at the battery to start with.


Sent from my HTC_0P6B using SAU Community mobile app
 

[Kinkstaah]

Just for the record, battery is new Optima Yellowtop (well, maybe 2500kms old). Voltage when on boost and hot is ~14.1V.

[Dose Pipe Sutututu]

See if your voltage drops as RPM increases, just log it in the halal-tech.

Add more dwell man, less will misfire, I have 3.5ms in the midrange for mine. I'll screen grab my table for reference when I'm home.

[Kinkstaah]

Voltage doesn't drop on boost, the autologging on the Haltech at the track shows it holding steady.

Isn't stock dwell something like 1.5ms on the stock coilpacks? I'm at almost double that so I figured adding more would only result in finishing off a dying set of coils (if its that)

[Kinkstaah]

Bought a brand new set of splitfires, and went manual.

Problem still occurs, on both sets of plugs!

I am at a bit of a loss as to how this can occur, I'm using Johnny's timing map (15-18 deg of timing on e85) and running 12 psi of boost I can't see why else this could be occurring.

What other parts are even involved? Other than orienting spark plugs so the ground strap faces the intake when done up I am out of ideas!

[iruvyouskyrine]

What's the state of your wiring harness?

[Piggaz]

As above!?!?

[Kinkstaah]

Loom is actually a new OEM one

Plugs however?



The thing is, both sets look like this!
I have since put in a new set of bcpr7es with the new coilpacks, and removed the coilpacks cover. Drove the car just now and all good.

As to what the tips look like on all these plugs.... They look normal, it is only the insulator pictured that has any damage.

[KiwiRS4T]

My Nissan Trained Japanese tuner told me to throw out my copper plugs and fit PFR7G-11S which I did.

You though may have found the lifespan of the Splitfires. No-one has yet pointed to a simple test for coils to see how they are holding up.

[Kinkstaah]

Could bad/failing coilpacks cause the pictured problem with the plugs?

Both sets of plugs did run with those coils after all....

I don't know how a coil could fail in a way that would cause cracking the 'upper' porcelain.

Is that feasible?