RomRaider

Hi all,

Im in the stage of tuning my new engine build 2.0L ej207. Could someone tell me what contributes to the jumps up and down in my ignition total timing? Trying to smooth it out. Any help/advice would be awesome. Thanks alot. Attached spreadsheet logs.

Mods:

Mods,
K&N typhoon intake
stock 380cc blue wrx injectors
fuel pressure reg tomei
perrin silicon intake turbo
td04-19t
equal length headers with decatted uppipe
bigger top Mount intercooler then the sti's
3inch full exhaust system 2 cats
adj cam gears cams dialed in
kevlar belt
custom grind cams
half 1mm half exhaust + intake stock valves, 2/2 each combustion chamber for swirl
ported and polished heads
tumble valve delete, shaft + motor still operates, took small butterfly plates out
ported throttle plate +shaft for more airflow
beehive springs with titanium retainers
fluidampr crank pulley
forged pistons + gas ported\ gapless piston rings
stock ej forged 207 rods + crank
killer b oil windage + oil pickup
lightweight flywheel + hd organic clutch

do you have permission to share the rom? being able to see that would help. I notice in both logs your fueling is not very spot on.

I'm pretty sure you mean dark blue top feed or light blue top feed densos, neither of which flow 380cc - which injectors do you have?

you're logging a bit of unnecessary extra data in both logs, and you're not fast polling, but I believe the specific issue of the base timing and total timing jumping around is due to timing compensations per rpm fluctuation of idle.

you've got to get that fueling error fixed. like I said, seeing the rom would help.

hi mate see attached for stock Australian gda wrx rom called scooby
other modified/tuned map called scoobymaffuel
I've attached recent logs I just did. thanks

I am pretty sure they are light blue I will attach a image of them. whatever came stock on the Australian gda wrx's

first off you're logging more fields than you need.

part of your problem is running a stock MAF scale on a different intake
moving the depth of the MAF sensor in the housing, changing the length or bends before/after the sensor, or changing the diameter of the area the sensor sits in all have an effect of airflow over the sensor, thus intakes need scaled.

plus, not only does it effect your fueling, but timing as well through airflow having a part in the calculation of engine load, and engine load is an axis for too many things.

if you can't get a wideband and scale your MAF then you might consider not driving it, getting it done at a shop, or putting the stock intake back in. your fine learned knock is scary, and your front o2 sensor swings a lot, I would bet you have either or both an issue with the fuel pressure regulator or an intake/exhaust leak

not to knock your work on your engine, but you leave a lot on the table with all those extra mods when you're running stock 420cc injectors and then for some reason upgrading the fuel pressure regulator? the stock one is fine, even for larger injectors and different fuel rails. Also, an intake change isn't needed since the stock one can read more airflow than the rom is hard coded to work for, so even if you uprated your fuel injectors to make more out of the turbo and thusly rationalize all the other work on the engine, you'd still be limited to 300 g/s, unless you half-maf'd it but you're not ready for that yet.

I would pressurize the intake tract at the turbo inlet, and do a seafoam treatment through the bypass valve to manifold pressure line. Separately, not at the same time. you'll find all your intake and exhaust leaks this way.

for whichever is your problem, just mechanical, mechanical and tune, or tune, I personally would go back to stock fuel pressure regulator and MAF, then go from there. The reason I suspect the fuel pressure regulator, is that tomei is a brand that is copied and counterfeited by overseas companies, similarly to HKS products - if you find a new SSQV for $50, it's fake. Junk fuel pressure regulator is in the realm of possibilities.

it would also help to read up on logging parameters, like what you want for what you're looking for and what you don't need when you're not looking for it, like logging IAM isn't a thing most of the time. a learning view pull before and after driving is usually good enough when feedback knock correction and fine learned correction are logged. I prefer logging both MAF voltage and MAF g/s, and logging engine load is only necessary once. logging idle control duty is unnecessary, your issue is fuelng. nobody cares about the rear 02 voltage, and logging tip-in with umpteen other logging parameters won't get you enough resolution in polling to make it useful. you could cut down to like 12 to 14 things and still get 16 - 18 polls per second, right now you're at 10 - 11 polls per second. Since we know that your injectors have an already solid latency and scaling (in the stock rom), you don't necessarily need both injector pulsewidth and injector duty percent.

idle timing flops up and down depending on how much rpm error you have, and rpm error can be exacerbated by fueling issues.

also, you've got three threads going on for the same thing. you can just keep posting in one of them, like this one maybe.

Hi mate,

Thanks for the reply.
Im still getting use to logging so I'll go through and log only the necessary fields next time.

With the intake. We have scaled it for the k & n intake it ran fine on the stock motor when we scaled. I can't seem to see how it could have a effect now. The maf sensor position / tube size / inlet size is stock so that rules that out. We'll look into that area though and let you know how we go. Are you happy with all the other areas of the tune? I've adjusted it to areas of your rom you sent me on the other forum post. Is there anything else you would change? I find the car does not like cruising around 2000-2400rpm. It can be jumpy, jerky most of the time. Is that flywheel a contributor to that? Or is that the Cams?

The fuel pressure regulator is a genuine from a big/good car parts seller which I paid around 200 for. I've checked it all the time by taking the vacuum hose off. It doesn't change. It's always on around 43ish psi. So that rules that out.

What do you mean the fine knock is scary?

The reason why we haven't moved to sti injectors yet is we didn't know what areas to adjust for the new injectors in there. So we would of been spending to much time trying to tune the injectors. Where we should be doing what we're doing now and sorting the small areas out. Then we can move to bigger injectors. The stock fuel pressure reg had 14 years on it so we thought we would replace it.

What I'm thinking, I've got a boost leak tester coming so I will pressurise the system and check for leaks. Then I'll do a seafoam into the bypass. I don't need much seafoam do I? Just a couple of squirts? I shouldn't have to change the engine oil after that?

So my total timing problem could possibly be:

Fueling - adjust maf scaling to suit airflow range at idle.
Intake/boost leak
Any others?

So rpm error? So what does the ecu look at exactly to take timing out + put it in like seen in the logs for my idle? I can't see any area of tuning adjustment for timing at idle, and most of the areas that I see don't take out and put in that much at idle.

Also mate the cranking fuel, now that i know its 420cc are you able to adjust the fueling for that? Thanks mate as I think you did it for what I said 380cc by accident.


I've just had a good look at my logs. The only thing that stands out to possibility contributing to the timing is the air/fuel learning. Do you know if this field effect timing as well as fuel?

Thanks for the help mate I appreciate it alot.

I had that on my EJ205. I found that it was mostly due to the shape and smootheness of the ignition timing. I also saw it decrease with stiffer driveline mounts. Also look into your idle ignition timing as well as when the car switches from idle timing to off idle timing. You may also want to add a little bit of wastegate at very low load to allow the ecu to help with load transitions.