I'm not sure a DME will predict based on what it's seen prior to the MAF maxxing out. Likely it hits the limit and begins referring to a table somewhere. I don't program DME but that would be the most likely scenario since doing any sort of estimating would take more computing power than I would expect and the OEM engineers likely didn't expect the MAF to ever be maxxed out with the power levels it left the factory equipped with. Maxxing out a MAF can also lead to blowing one - at that much airflow it's going to be heating that sensor for all it's worth, a sudden drop in airflow could lead to it popping like a Christmas bulb. I know some have had really bad luck and some have had great luck - I've been lucky but also haven't maxxed mine I suspect. Just something to consider is all, I think MAF based tuning is better from an OEM standpoint and would consider it for aftermarket too if it were easier on this car.

I've tuned Speed Density to feel like an OEM vehicle before - it took a good long while! That was a different platform and a different much less capable ECU with a really poor learning capability that no one used. AEM V1 baby, I used to beta test their firmware. Correctly tuned the car will run well and with a base tune and E85 tune done by Garth I hope to have little tweaking to do honestly. I want the added safety of the aftermarket ECU and I want the ability to dump a few FEET of intake piping Don't think I'll ever be knocking on 1K+ HP with this car but I want it to be able to run E85, drive nicely, and boost safely. 15 years of additional ECU development will allow that I think plus I love to tinker!

P.S. If you're picky enough and drive enough OEM cars you can actually find bugs in their tuning - driveability quirks usually. Tune driveability enough on an aftermarket ECU and you tend to get pretty picky!

 

predict is probably the wrong word since the OE DME isn't a 'learning' unit
Although probably company/tuner secret, would be neat to see how each tuner deals with the maxing of the MAF, and agree it is most likely looking at a more open-loop-like map once the limit is reached(if that makes sense)
Let me guess the platform, DSM? lol, I still have buddies' messing around tuning them..
Newer standalone systems seem really comprehensive and the only way to go for true HP monster/ full-race machines.
And definitely some of the OEM tuning is garbage, notice a lot of cars made in last 10years or so ha had some really quirky and laggy tuning(overall under-developed or extremely conservative on the emissions side)...but some of it is really good, Porsche has always done well IMO
Cheers,

 

Nah, was a Supra Had one of the first units they shipped. It's in the garage in what's left of my totaled Supra - it will live again in a 240Z once I get off my *** and finish pulling the drivetrain for the swap - oh and get the rear sorted.

Bummer the DME doesn't "learn" but I'm not sure I'd want an ECU that far back "learning" anyway. In the fenderwell intake thread Tony talks about this problem with the MAF a little bit, maxxing the MAF isn't uncommon apparently. Overall I think the stock DME does a good job but I'm a data junky, love the safeties of stand-alone, and want flexability with boost delivery. Oh and E85, I'm loving that there's A station here that sells it Most of the poor OEM tunes I've seen stumble predictably or have just odd quirks. Having spent so much time on my Supra getting cold start and other tweaks juuuuust right I notice this crap. <shrug> Hopefully i won't sped nearly so much time with my ProEFI - we shall see!

 

+1 as i'm in that former category, i only seriously considered a maf less proto as i was having constant maf issues, but since a NEW oem 124.00 cured all my ills, i wouldn't give another thought to mafless, while standalone ecu plus accompanying goodies will always be a back of my remaining mind ( and i hope it stays there! ) option. i just know i'm in the sweet spot power wise and this bit*h aint getting any younger miles wise so thinking 550+ rwhp is plenty for a 125k+ mileage motor! i push the car, but hopefully, not my luck.

 

Anyone ever use USP motor sports for any parts? There maf sensor is $50 cheaper than pelican.

 

Theyre on my parts list of places. I think they had the maf now for 275?!

Plus Chris is pretty cool and just answered some.dumb sh*t for me.
That keeps places like USP on my "list" of parts places. But I have to say i do use pelican a lot.

 

bosch 0280218009 185 on amazon.

 

Just come buy lets log it once and maybe save the money.. cleaning it did help...

 

had car out this weekend, ran great! I was just thinking bout it for piece of mind.... Car is sooo much better now than when I first brought it to you. Thanks again for all ya did!