[John Neil]

Got it into the car last week. Using SCtuner software, which is amazing. So far:

Pulled fan temperatures down, changed idle points, redid spark table scaling, added a few degrees up top at WOT.

My main purpose in getting it was to reconcile a few miscommunications between my C&L MAF and computer at very light load. My computer is relearning and isn't stable yet, so I haven't yet done this (slight tinkering with MAF transfer function will be all it'll take)

What other changes have yall found helpful? I only added about two degrees max at WOT. Somewhere I read that there's a few extra ponies to be gained, and I feel like I found a few, but hopefully there's more. Maybe once I get to it I can tweak fuel and spark at cruising speeds and loads to help my cross-country style driving mileage.

Fuel table scalings? Same as spark? I really don't understand their function. Let me know what all yall have found. Thanks.

John.

'93 SC auto

 

[MagerThom]

John......sounds like you're doing fine so far.

To be honest....most of us have chosen not to get into
reprogramming our EEC's. Not that you can't, as you have
demonstrated. But now you're looking at more complicated
changes.

Have you eliminated the WOT retard function? Between the
interdepedency of the various tables functions and parameters
AND then the relearning function - which is essentially an
internal reprogramming ability - according to "the man with
no name" it takes years to get really facile at making a
lot of, what turn out to be very delicate, alterations to
the EEC's programming.

If you want to pursue your programming, that's great.
My suggestion would be: go to this site, join and ask
the Advanced Tech Forum's moderator what you want to know.
He is the ONLY person I'd trust with respect to altering
my EEC's programming. I wouldn't trust any of those "experts"
that work for the big chip or programmer companies at all.
My guess is they have hacked their way to marginal stability,
while not having a clue concerning true functional theory.
Obviously those who are associated with "the man with no name"
are excluded from my neagative assessment of the field of
"experts" out there. I have no doubt he has forgotten more
about proper programming than the rest of these "experts"
have ever learned.

http://mtcforum.zeroforum.com/zeromain


BTW - He just happens to own an SC.

Good luck,

 

[GreenBird]

a dyno run with wideband o2 sensors would help...it will effectively measure you air/fuel ratio. leaning out the mixture will help with more power and better mileage, but be aware of detonation and it's consequences.

I would talk to Dr. Fred Holzter(sp?) and/or Coy Miller too. They know their stuff.

 

[John Neil]

tuning

Okay, so I see what yall are saying. I reread my post and I would warn myself of the same thing. I agree, I sounded like I needed a bit of calming down. I am very aware of detonation and the dangers of fooling around on origional head gaskets in my car. I definately do not plan on making huge changes, throwing in huge timing, and still being able to drive the car.

My MAF issue mentioned has been a problem since I've had the car 40k miles ago. It backfires under extremely light loads if you nose in on the throttle (from none to very little) between 1000 and 2500 RPM. It's a lean miss, that sometimes freaks the computer out and causes the engine to buck when the torque converter is locked out. I've lessened the problem by moving the MAF around within the intake path, altering it's positioning, and slight changes in the sampling tube. I'll be glad to get that fixed. (slight tweaking only, I promise)

I guess I was just looking for someone to say "hey, look at this table and try some slight tweaks in this range for...." Thanks for the suggestions. I've been keeping tabs on all the tuning discussions since Rich got involved in trying to put an EECtuner into practice. I suppose it'll be a bit handier over the next few months with injectors (42), headers, fuel pump, and some head reworking. Thanks again, John.

 

[MagerThom]

Smart moves...

in your case I'd say go for it as you really seem to
have a handle on the situation and you're not
trying to force the "real" reality of what you're
doing into something it's not.

Once again though, there are a lot of "experts" out
there that talk a good game, but really don't have a
clue. Just because they haven't blown up their own
car....yet....doesn't confer upon them the title
of "automotive computer design engineer."

My feeling is: why go anywhere else when you can go
to the source? (That link I gave you.) If you are as
balanced and polite to him as you have been on this
site - he just might help you.

Let us know if you get the help you need. If you don't,
there are a couple other ways to accomplish the same thing.

 

[Blown306]

Yes...contrary to Gordon Gecko, greed is not good when it comes to engine tuning. You have a little bit of a challenge tweaking the C&L MAF function because you don't get the flow sheet with it. At least with the SCTuner you can see the curve to help keep it smooth. If you cannot do datalogging, I would suggest running test leads from the MAF to inside the car and get the voltage reading of the MAF at your problem area. Then tweak the curve at that point, that should get you in the ballpark.

Another table you might want to look at that I'm playing with is the dashpot decrement rate...to try and drop the engine to idle quicker (like a carb car).

Also, like was stated before, a wide band and dyno is going to be necessary for a good tune...otherwise, you are stabbing in the dark. There are DIY kits out there for those. If you haven't joined yet, definetly go to the EEC Tuner group at groups.yahoo.com. Fred H frequents that quite often, and knows his stuff, especially on the Super Coupes. Also, the MTC boards are excellent as stated above, with some true experts on those boards.

My plan is to get most of the big knobs turned, then take it to a certain un-named expert to adjust all the little knobs....