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Discussion Starter #1 (Edited)
This is in an A31 Cefiro, but assume it's an R32 GTS-T since they're the same thing engine-wise, RB20DET. It only has minor mods, namely an Apexi intake and a 3" turbo back decat exhaust.

I've just fitted some Splitfire SF-DIS-001 coilpacks. Initial test shows a big improvement. The car now starts instantly and no more misfire under acceleration. Not bad for an hour's work.

The manual has a warning saying that after fitting them, you may get knocking/detonation and should adjust the timing to suit. I'm fairly sure the timing isn't adjustable on these engines. Is that the case?

Should I be disconnecting the battery to do an ECU reset, or is that not a thing on these ECUs?

I'm also thinking that next time I go into that area, I want to get rid of the pointless cover. Literally the only use it serves is to provide a mount for the power transistor. Question is where is a good place to relocate the power transistor to? Should I just cut the cover down to just the last 4 screws as even this will make it less annoying to deal with as it won't conflict with the J pipe.

Anything else I should know?
 

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The RB20DET has CAS to set base timing via timing marks on the crank pulley, not quite sure why the makers say the coils could cause det, that would only happen if the ing timing was too far advanced or retarded, or if the fuel was very low octane and the engine was laboured, just changing coil packs shouldn't make any difference, apart from giving a better more intense spark.
 

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Discussion Starter #3
The exact warning is
Splitfire said:
2. After the installation, as a result of increase of ignition energy, ignition timing may become faster and knocking may occur. In such case, ignition timing should be adjusted as needed. If knocking continues for a long time, the plug may melt and in the worst case, the engine shall be broken.
3. Replacement of plugs into colder heat range is recommended as the ignition energy will increase and the temperature of combustion chanber will become higher.
4. Manufacturer is not responsible... etc. etc.
I have bad memories of attempting to do the timing with a strobe light on an Mk4 Escort. Don't fancy doing that again... garage job? That will be annoying after doing the change and only losing one screw and breaking one fingernail!

The plugs I have are NGK BCPR6EIX-11 not sure if those are standard or colder as suggested.
 

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The plugs he has are pre-gapped to 1.1mm, hence the -11 at the end of the part number. They should be gapped to 0.8mm instead, and also shouldn't be iridium since they're a waste of money. Get a set of bcpr6es plugs instead.

And no, don't change the timing unless you already know it's out. It's easy to set with a timing light though if needed.
 

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Discussion Starter #6
So what it that warning all about then? I quoted it verbatim complete with the original Engrish.

Am I just being paranoid and noticing something else? It sounds like tappits in a pushrod engine, but quite quiet and only under load.

Is dropping the gap to 0.8mm really that important? There are no misfires and the car starts beautifully now. Surely replacing with non-iridium would be an even bigger waste of money as these ones still work :)

Also less of the he, I'm a she :p
 

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Just to add, don't try and adjust the gap on iridium plugs as they are very brittle and could cause problems, as said copper core plugs are fine, and unless you have increased the boost you should be OK with the std 1.1mm gap, especially with the uprated coil packs.

The warning doesn't make any sense as like I said its only the spark energy that increased not the timing, the combustion process may become more officiant as a result, but unless the mixture is weaker there is no reason for det, I think they are just trying to absolve themselves just in case.
 

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Discussion Starter #8
That just leaves the question of what the hell is that high pitched clicky tappy noise under load?

When I say load I mean even gentle acceleration on a flat surface.

I have not done any boost mods, though when I swapped out the stock airbox for the apexi cone filter that did increase the peak boost from 0.7 to 0.9

The car is run exclusively on 99RON V-Power, though I believe the stock ECU is expecting 100?

Sorry if I'm seeming rather paranoid about this. In the past I've killed the engine on a Legacy B4-RSK due to detonation and it cost me 3 grand to sort out.
 

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So what it that warning all about then? I quoted it verbatim complete with the original Engrish.

Am I just being paranoid and noticing something else? It sounds like tappits in a pushrod engine, but quite quiet and only under load.

Is dropping the gap to 0.8mm really that important? There are no misfires and the car starts beautifully now. Surely replacing with non-iridium would be an even bigger waste of money as these ones still work :)

Also less of the he, I'm a she :p
LOL! yeah I caught the broken nail bit, if you think your actually getting det, although I really cant see how, but if that what the manufactures say then maybe check that the ignition timing is set correctly in the first place, and maybe retard a degree or two just in case, but if they feel the need to issue a disclaimer then it may be prudent to check the timing to be on the safe side.
 

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Discussion Starter #10 (Edited)
And in that case I have all the fun of finding a garage that still knows how to use a strobe light.

They'll also need a knock sensor won't they, if this really does throw the timing out.


Edit: Also any suggestions what to do with that power transistor so I can get rid of the coil cover?
 

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That just leaves the question of what the hell is that high pitched clicky tappy noise under load?

When I say load I mean even gentle acceleration on a flat surface.

I have not done any boost mods, though when I swapped out the stock airbox for the apexi cone filter that did increase the peak boost from 0.7 to 0.9

The car is run exclusively on 99RON V-Power, though I believe the stock ECU is expecting 100?

Sorry if I'm seeming rather paranoid about this. In the past I've killed the engine on a Legacy B4-RSK due to detonation and it cost me 3 grand to sort out.
You really shouldn't be getting det during gentle acceleration, unless you have too higher gear selected, I would get the timing checked anyway, the noise may just be mechanical noise but best be on the safe side.

I would also get the fueling checked, as if the fuel pump, injectors or filter are restricted that could cause weak mixture and lead to det, don't worry about the 100 RON bit the std knock sensors should tell the ECU to retard the ing timing if its indeed causing det, but I doubt that's the case.
 

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Discussion Starter #13 (Edited)
Well mine's an auto so if it's in the wrong gear I have much bigger problems :)

According to my multichecker it's idling at between 18 and 21 degrees, haven't checked what it's setting it to under acceleration as it's fallen off the dash and the cops don't like you driving around with a random illuminated plastic gadget in your hand :)

Fuelling is going to be a bit harder to check, but I'd hope with only 70,000km on the clock and me as the sole UK owner that it would still be ok.


Edit: The removing the coil pack cover thing I think comes from the SXOC crew where the general wisdom is that you remove it if you don't want your coils to overheat and die. My partner has removed hers from her S13 and it's been fine for the last 5 years. Is removing it not the done thing on Skylines then? I kind of figured the experience would be similar since an RB20 is basically just a CA18 with two extra cylinders and slightly smaller.
 

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This is in an A31 Cefiro, but assume it's an R32 GTS-T since they're the same thing engine-wise, RB20DET.

Question is where is a good place to relocate the power transistor to? Should I just cut the cover down to just the last 4 screws as even this will make it less annoying to deal with as it won't conflict with the J pipe.
Not quite the same as an R32 20DET, there is no standard BOV on the A31 20DET and I believe the turbo is built slightly differently due to the lack of a BOV. Pretty trivial differences though :)
Why relocate it? Just leave it there... or flip it up to vertical and cable tie it to the brake lines.
..but yes, it is commonly removed to let coil packs breathe!
I've removed mine... but imo the engine looks "unfinished" without something there so I made my own cover. It's angled bumper mesh, 2 layers thick with the angles going in opposite directions so you can't see through it. Alloy flat bar borders it and gives me something solid to tighten screws.

A pic always helps...






The coil pack cover stops water getting on the electrics but its upto you if you want to remove it...
Why anyone would be pouring water into that area, I have no idea :confused:
Also, what electrics? There are far more electronic components NOT under that cover, yet still in the engine bay...








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The statment about having to adjust the timing does not make sense

When they say adjust, they are referring to adjusting the ignition map in the ECU to suit as if adding the new coilpacks will add ignition. Its a bit confusing imo as you are only potentially increasing the spark energy and not the actual ignition map
 

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Discussion Starter #16
Panic over.

I got my partner to have a listen to it. She is better at this kind of thing than I am.

Results:
It's only happening on one cylinder
It gets better overall as it gets warmer.
It gets worse under acceleration

Conclusion:
Most likely an exhaust gasket.
Possibly also a noisy tappet.

Annoying, but I have more important things to worry about.
 

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brett
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Why anyone would be pouring water into that area, I have no idea :confused:
Also, what electrics? There are far more electronic components NOT under that cover, yet still in the engine bay...








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You wouldn't pour water in there,that's just stupid,but condensation and **** can get in around the coilpacks and plugs if you remove the cover (what electrics? Lmao)
 

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Leave the cover on..
The previous owner of my car removed it, and when i wanted to change plugs, i had to remove about 30cc of sand and small stones before removing the plugs.
 
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