Speed Density on Evo ECU

[turbotalon1g]

sounds cool, and pretty much what everyone on link has been saying.
A PITA to dial in, but once done everyone loves it.

[bananas]

Very cool stuff! I'm jealous I can't do this kind of thing with my car. Of course, if I could I'd probably end up blowing something up!

[scheides]

^your owwdee will run speed density from the factory! You know how you can just unplug your maf and it keeps running? yea. punk.

[scheides]

So much for 'waiting till this weekend' LOL!

The big improvement since yesterday is in the fuel trims, I have them dialed into right around 0% for LTFT mid. Also leaving from a stop the car would want to stumble and die, some logging showed that load jumped into the 80 range and AFR leaned out to 18:1. Tweaked the SD MAP VE map a bit and fixed that, stays in teh 14's now as I leave from a stop and no stumbling!

Here's where I'm at:
http://scheides.com/misc/pics/evo/speeddensity/sd-test4.JPG

My LTFT Low is still at -12, but I haven't let the car idle a ton. While giving my buddy a ride the other day he was semi critical of the idle, which I had left around 1200-1250 rpm. I was super happy because of how it would not dip below that at all, and he was saying he thought it really should be lower for me to say its 'solid'...anyways, I made one tweak to idle rpms (haven't touched any of the ISC Stepper tables or anything yet!) and bam, the car idles at about 900rpm, maybe 925. Logs show 900-950-1000 but the tach needle just sits dead inbetween the 800rpm and 1000rpm tick marks. Kelford cams, ported head, ported everything else, not a single dip or stall, its absolutely mindblowing!

Going to review some of my WOT logs and see where timing is at, but boost is set at 19psi now and afr is in the high 10's on my wideband. Ready to get back up to 24psi and try and get dialed into my old tune. I have yet to touch AFR, timing, injector scaling or latency values aside from translating or copying them over from my old map.

Ooh, also, the car seems jittery while its warming up, and I've noticed that at 2000-2500 rpm while cruising sometimes it feels goofy to. AFRs are around 14.5-15 so need to see what else is going on to cause this. It is very subtle once warmed up.

[scheides]

Friday update. Back up to 25psi! Its amazing how fast the car feels after its been down on power (or limped or whatever) for a few days. All of the little boost control mods v7 has to offer really make the car responsive and when its dialed in the car just rips! BBK is holding 25psi dead flat from 3800 out to 7700rpm (highest I've logged so far) with about 84% WGDC. Bryan@GST did note that he had to tweak WGDC a bit to bring boost inline with where it was before, and here's what I noticed: I needed a bit more WGDC down low during boost onset, and had to take a little bit out up top, boost was off by about 2-3%. I literally made two changes and logged a few pulls in a few different gears and its perfect again. I LOVE this ecu controlled boost setup once its dialed in!

More on topic, I have yet to touch my AFR or timing maps that shane@DB made for me (and I hope to not have to, this tune has served me VERY well this summer :D) My load up top is a bit high now, so I'm droping down the highest valve on the MAP VE table from 430 to 410 to see if I can slowly get load back to where it was before on the street. It's peaking in the 330's and tapering to ~300, before I was peaking at 280 and tapering to 250 or so. I'm also now using 1byte load vs 2byte load, so I'm focusing more on the timing values the car is running moreso than the actual load numbers I'm logging.

I had accidentally misread the EGR timing advance under cruise bit and disabled it (vs enabling it, the bit is backward, it reads 'disable EGR timing advance' 0 is enabled, 1 is disabled). I knew about this already and totally spaced it. Anyways its worth mentioning because my car drove like isht when it was cold and wanted to jerk when warmed up and cruising at low speed. As soon as I turned this back to 0 and put my EGR Timing Advance timing tables bumped up to where I had them before (bumped just slightly from stock, 6's and 8's) the car drove as it had before.

Still getting this ever so slight jerkyness when under low low load while cruising in the 2000-2700rpm range, which is a fairly widely known issue with this speed density setup and I would rate it at very mildly annoying and often not noticable...but Slo_crx1 on evoM posted up last night that he thinks he has eliminated this issue using the new tables that mrfred posted re: advanced fuel control and globally increased the values in the Asynch vs TPSDelta table (sort of a TPS tip-in type control I think). I'm going to try this out today as this is potentially a huge break through on this project.

I'm going to try these settings out, dial in my loads as mentioned above, and just bomb around for a few days and see how it goes! It's SO easy to focus on the laptop its getting to be time to just drive the car and see how it feels and just enjoy it. Once I'm happy, alky will be flipped back on and back up to 30psi!

Oh, does anyone know, can I just unplug my MAS? I'm toying with the idea of either gutting out an old MAS I have (w/ a destroyed honeycomb) or getting a 3" inlet perrin filter and just strapping it to the end of my buschur intake.

[jrohner]

Yeah you can get rid of the MAS. It's not being used for anything. It won't trigger a CEL or anything as long as you have an IAT sensor somewhere else, which you do.

[turbotalon1g]

SOunds awesome, that delta tps tip in deal is only used for enrichment for a very slight second, depending on how bad your hesitation problem is that may or may not be it.
good luck.

[Matt D.]

How has your cold start idle been?

[jrohner]

Mine started up and idled great on SD (idle was better both cold and warm on SD), but trying to take off on a cold/cool engine was a bitch.

[scheides]

Cold start has been fantastic, as well as initial cold idle and warm-up idle.