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Yes. I'm going to be running thinner oil as well but it's setup for high pressure. I have an additional haltech oil pressure sensor I'll pull off that log to see exactly what it was.

FYI the Tomei pump is adjustable. And in the instructions they tell you that you should have additional oiling capacity (ie- deep sump) if you run their higher settings.

A thinner oil will give me a little lower pressures and allow the oil to drain back to the pan faster (ie-less crankcase ventilation issues potentially). I think I'm running 10-40 for break-in.

Also I did install a brand new pressure sensor when I built the motor and the Haltech is really neat in it's engine protection funtions. I have the 0-150psi haltech pressure sensors on my fuel rail and my oil system. Both of them can be set up to do all kinds of things to the engine (limit rpms, illuminate lights, etc) when certain conditions are met (which are also editable).

Grrrr..

Drove to car show. No leaks. Good power, decent mileage. The longer this car runs the worse it feels on ONE certain dead spot in either ignition or a mechanical issue. It's a well defined BUMP in the idle that is very consistent...and worse and worse as it warms up and you drive it. Sitting in traffic the car starts to get very hard to drive.

Fuel pressure is perfect, so is oil, air temp, etc.

Checked compression:

1 - 165

2 - 170

3 - 165

4 - 172

5 - 170

6 - 170

Then pulled cam covers and checked cams:

I measured:

Intake: (Tomei target is .018" +/- .001")

1a .018"

1b .016" out tight

2a .016" out tight

2b .016" out tight

3a .018"

3b .017"

4a .020" out loose

4b .021" out loose

5a .018"

5b .017"

6a .020" out loose

6b .016" out tight

Exhaust: (Tomei target is .015" +/- .001")

1a .012" out tight

1b .011" out tight

2a .014"

2b .014"

3a .013" out tight

3b .013" out tight

4a .012" out tight

4b .014"

5a .014"

5b .014"

6a .011" out tight

6b .013" out tight

I still can not figure it out. pretty rough idle...but constant miss. After you run the car up to temp it just starts missing at part and low load cells (has a lean-ish backfire at 2500-3500 getting on boost. Sounds like ONE specific cylinder too. I thought for sure it would have been a tight valve. These valves aren't THAT tight IMO.

Coils are new splitfires (hey maybe one is bad?)

plugs are new NGK 8's. I also threw 7's and 6's in there to see what the deal was.

Car still pulls like a freight train after you get it going at full throttle but the stop and go traffic I look / sound like an idiot driver...especially after it heat soaks and starts breaking up. I put a ground on the igniter just to make sure. Possible I melted part of a valve? Acting like an intake valve if so? I'll do leakdown check later this week.

WTH guys any advice on this? Haltech seems to be responding very well to changes...logs on pulls look good and AFR's at part throttle seem reasonable. It idles way too rough for these small cams with defined burble.

exactly.

I'll grab my hand-held laser thermometer from the shop tomorrow and see which cylinder isn't firing correctly. I'll gun them all at different times of running (start, 5 min, 20 min) and see if there is a defined difference. This could very well be ignitor / coil related or related factory wiring related. Wiring wasn't crispy, so I didn't think it could be that, but I'll start there tomorrow then play the "coil swap game". Also none of the plugs or cylinders looked wet / dry compared to others. Plugs looked all the same. I guess there is a potential that I have a dead injector as well. I guess with new motor and all I just erred with mechanical components.

oh and to clarify. It ran REALLY well for quite some time. But I honestly hadn't driven it long enough to really heat things up. I will be pulling parts of the ignition harness and looking more closely at it shortly. Looking into trouble-shooting information now.

Yes. I'm going to be running thinner oil as well but it's setup for high pressure. I have an additional haltech oil pressure sensor I'll pull off that log to see exactly what it was.

FYI the Tomei pump is adjustable. And in the instructions they tell you that you should have additional oiling capacity (ie- deep sump) if you run their higher settings.

A thinner oil will give me a little lower pressures and allow the oil to drain back to the pan faster (ie-less crankcase ventilation issues potentially). I think I'm running 10-40 for break-in.

Also I did install a brand new pressure sensor when I built the motor and the Haltech is really neat in it's engine protection funtions. I have the 0-150psi haltech pressure sensors on my fuel rail and my oil system. Both of them can be set up to do all kinds of things to the engine (limit rpms, illuminate lights, etc) when certain conditions are met (which are also editable).

Tomei pump is adjustable but you need a couple of things to do a decent job of it:

1. A bolt to screw into the housing on the outside - you bore it out a little so the spring has more length to work with.

2. Springs. The two Tomei send you are either too much is used together or too little if you just use the one large one.

So what I did was used a spring from a Nismo pump and set it such that it has 3mm longer (From memory, I think) to work with than with the Tomei bolt. Gives you lower pressure at idle but larger pressure at higher revs than just a single Tomei spring.

  • Like 1

Tomei pump is adjustable but you need a couple of things to do a decent job of it:

1. A bolt to screw into the housing on the outside - you bore it out a little so the spring has more length to work with.

2. Springs. The two Tomei send you are either too much is used together or too little if you just use the one large one.

So what I did was used a spring from a Nismo pump and set it such that it has 3mm longer (From memory, I think) to work with than with the Tomei bolt. Gives you lower pressure at idle but larger pressure at higher revs than just a single Tomei spring.

Thanks for that.

I pulled the datalogs for the oil pressure when warm (198 deg F)

30 psi at idle 1k rpms

65 psi at 2400 rpms

80 psi pretty much everything above 4k.

So I see what you are saying it's not linear at all.

Again on 10-40 oil. I will go to thinner oil since this pump is apparently stupid high pressure and flow right now.

Thanks for that.

I pulled the datalogs for the oil pressure when warm (198 deg F)

30 psi at idle 1k rpms

65 psi at 2400 rpms

80 psi pretty much everything above 4k.

So I see what you are saying it's not linear at all.

Again on 10-40 oil. I will go to thinner oil since this pump is apparently stupid high pressure and flow right now.

Yeah it worried me when I put the pump in my engine. Still don't like it as a pump but there isn't really a good RB26 solution, even after all these years.

as soon as I get my other issues sorted I'll move to a 0W-20 oil and see what it does. My idea is that my clearances are nice and tight and that the lower viscosity will linearize the oil pressure curve a bit as well as to reduce drag and also increase circulation rate of oil back to the pan. An experiment for a bit later though!

Fyi it's definitely on no. 6. Pulling injector wire doesn't make much difference. May be the ignitor. I'm going to check that first.

So ignition checks:

1) Ignitor / PTU bench tested all three circuits at both polarities (easy work) = PASS

2) Check harness connections from the ignitor/PTU back to the ECU pins to make sure there is continuity there = PASS

3) Check coils on bench, then swap coils to see if it moves = PASS

4) Check harness from PTU to coils for continuity = PASS

5) Check coils for spark by disabling injectors and doing spark gap testing as rolling engine over = PASS

Then Fuel check:

1) Check harness from ECU pin to fuel injector to verify continuity = PASS

2) Check fuel injector resistance = PASS

3) Swap fuel injector and see if problem chases injector = FAIL

EDIT - FOUND PROBLEM!!!

Problem was a bad brand new deatschwerks 800cc injector in no. 6. Passed resistance tests, just didn't flow like the others (pretty much no flow). No clue how that happened.

Swapped to a new set of the EV14's (actually used from my brother's LS project, but whatever they run GREAT.

as soon as I get my other issues sorted I'll move to a 0W-20 oil and see what it does. My idea is that my clearances are nice and tight and that the lower viscosity will linearize the oil pressure curve a bit as well as to reduce drag and also increase circulation rate of oil back to the pan. An experiment for a bit later though!

look forward to your next rebuild

Ok maybe not!

Good quality 10W40 Redline or even 5W40 its a balance between flow and support. That 0W20 has half the support than 10W40 at 100 degC but flow almost the same which is what you want for cooling, pulled my engine down recently for a look after 8 years on Redline 10W40 and bearings were a good and could have gone another 8 years easily. Track it a bit, which is the only time I flog it. Have a tomei pump/stroker similar set up to yours with oil pressure same as yours and making around 510awhp.

Will fit an EFR 8374 in around 1 week so looking forward to doing that.

Good luck anyway!

Edited by Meathead

Fyi...effing bad brand new deatschwerks 800cc injector! I'm now running EV14 style 850cc. Set new resistor setting (gotta love Haltech) and tweaked dead times. Car runs awesome again

Going on the racing scales shortly (forgot my buddy has a set)!

Any guesses? I'm betting dumping the twins, intake manifold, BOV piping and moving battery has netted me a good loss.

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