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Doing some SD tuning and have worked myself in a circle today. I own multiple mitsubishi's and having paid multiple tuners to tune this car, as well as my others with less than satisfactory results, ive decided to tackle this car myself. It seems to scare some tuners away as its a 2g eclipse on an evo ecu with a 9653 ROM. It was semi tuned prior, but after going back and forth with the remote tuner i finally gave up as it was a chore to get setup with him. I've started fresh with the following-
98 GSX, stock long block, small 16g, FMIC, 3" exhaust, 1120cc FIC's, pump 91, JDM 3 bar map. The car is fairly stock, so i figure itd be a good one to start with. Im more so just looking for some direction and guidance, not someone to tune the car. I've spent most of the afternoon altering everything from latencies to VE and i keep going in circles it seems. If someone can look at this log and give me some direction thatd be great. I know enough to get me in trouble, as well as to know that my settings aren't correct, but it seems everytime i change something i just go backwards with something else. i've included a reasonable spectrum of driving in a short log. I disabled closed loop as the o2 isn't cycling properly, not sure if thats my settings or if it took a dump. advice? criticism?
I started with good known injector scaling and latencies.
Dialed in target afr with rpm ve and map ve.
Then brought trims in with latency adjustments.
Im no pro but thats what worked.
That’s how I started as well, my idle kept going rich regardless of how much I adjusted RPMVE (45-50s), noticed the o2 was sitting around .1v when it was idling at 12.4AFR so I disabled closed loop. That allowed me to get my idle back around 14.5 but RPMVE is in the 80s for 500-1500. I was able to free rev up to 4K with good looking AFRs so I stopped there, went inside to take a break. Came out 2 hours later to see how cruise was and free rev was Super lean and cruise was almost undriveably lean (18-19AFR). I hadn’t changed anything from before, MAP still reads correct, IAT is correct. I’ve had the same problem all day of going back and forth like that. I know RPMVE should be in the 60s range at idle and work it’s way up into boost so I know something is being weird. Hoping someone has some insight from looking at the log
Main map, I have not setup the alternate map yet as I want to get the 91 tune dialed in before setting up the e85 tune. It won’t even run on the alternate map settings
Posted, this is where I've started over with. I haven't touched the MAPVE as I've been more focused on getting the RPM portions lined up, throttle tip in and MAP change hasn't been an issue worth addressing *yet*
Originally Posted by RightSaid fred
You haven't mentioned the pump?
After the pump comes the pressure.
You've got to have that right before you mess with software.
So the next step is to measure the pressure.
No, not the next step.........the first step.
After that........the IAT sensor has to be in the manifold for it to work properly.
Otherwise it's NOT an IAT sensor.
I guess I should've clarified better in my post, this is not a mechanical issue with the car. Its a tuning issue. The car has been previously tuned and works fine on the prior tune aside from some annoyances with the driveability that no tuner on any of my other 7 Mitsubishis can address to my liking. That's why I'm starting fresh on this car as it's relatively stock and an easy starting point.
That being said the pump has 43psi base pressure, 38psi under vacuum and raises 1:1 with boost as it should. The IAT is placed in the upper intercooler pipe where it should be and works perfectly fine as shown in the log.
Expecting you have good previous good injector scaling and latency. Your trims should be near 0. Now you jump into sd. Set rpm ve like i said too 100. Now go and do wot pulls in 3rd gear from 2k. Do it in increments. From 2k to 4k. Adjust map ve till your afr is good from 2k to 4k. Then raise the bar from 2k to 6k. And so on until you get to redline. This needs to be done with a good known octane map that goes richer as load goes up
Also your timimg map need to be conservative until you dial in a safe afr. Then once afr is safe you add timing advance. To mbt.
As ive learned the map ve will make your load go further to the right on the ignition or fuel maps.
Start over the weather plays a big toll in the speed density game. Dont give up and keep reading.
The spec for fuel pressure at idle is 33 PSI, not 38 PSI....it's in the manual.
Because you're not at sea level, your pressure will be a bit higher.........maybe 34 PSI which is still 4 PSI too high.
The other problem which "kids" always get wrong is the IAT sensor should be in the manifold.........as all factory SD installs are.
The throttle causes a pressure drop and also a temperature drop.
When it's closed at idle, you get the maximum temp drop.........it should always read colder in the manifold at idle than in the UIC at idle.
Temperature and pressure make density.........that's what the computer uses.
Originally Posted by 4b11slayer
Dont listen to me. I've got no idea about anything
Just because a flock of sheep get it wrong all the time........doesn't make it right.
More modern cars which come factory with SD use a single Bosch sensor which outputs both temp and pressure.........which of course NEED to be taken from the same location in order to be accurate.
Last edited by RightSaid fred; Oct 22, 2017 at 06:11 PM.
The spec for fuel pressure at idle is 33 PSI, not 38 PSI....it's in the manual.
Because you're not at sea level, your pressure will be a bit higher.........maybe 34 PSI which is still 4 PSI too high.
The other problem which "kids" always get wrong is the IAT sensor should be in the manifold.........as all factory SD installs are.
The throttle causes a pressure drop and also a temperature drop.
When it's closed at idle, you get the maximum temp drop.........it should always read colder in the manifold at idle than in the UIC at idle.
Temperature and pressure make density.........that's what the computer uses.
Just because a flock of sheep get it wrong all the time........doesn't make it right.
More modern cars which come factory with SD use a single Bosch sensor which outputs both temp and pressure.........which of course NEED to be taken from the same location in order to be accurate.
I realize you have this notion that you know it all, but I’ve been in the game long enough to know that you don’t. The fuel pressure is fine, even if I had a mechanical issue with the pressure I’d have a rich condition being 4 psi over what you assume it should be, not lean. My pressure is fine for my engine vacuum as well as my altitude.
The IAT is perfectly fine in the UICP. People including my other 7 mitsu on SD have worked fine for years with it in the same place. If you’ve ever measured IAT pre and post Intercooler as well as in the manifold you’d easily see there’s no temperature difference between post and manifold. It’s 3” and air is constantly flowing at a rapid rate. It doesn’t change. Thanks for your attempt at helping, but really I don’t need it. Slayer got me on the right track for getting it dialed in and it works fine now.
Oct 15, 2017, 08:05 PM
