being that far rich I personally would raise the injector constant a bit. Is the fuel pressure higher than the injector flow is rated at? Sure about the injector size? From what ive seen, changing the injector constant by as much as .5 or even 1.0 at a time is not too rediculous. but when its somewhat close ive been changing it about 0.1 units at a time. if its not rich due to injector constant or fuel pressure, then sorry but im not sure.

First, GM is notorious for making these cars run "rich"...less chance of warranty claims

That is why one of my beefs with "off-the-shelf" eproms is they tend to add fuel...and extra fuel is the LAST thing that is generally needed on a basically stock engine. However, it is why guys with a number of mods MAY find the "off-the-shelf" eprom works reasonably well.

But, be very careful about fuel pressure. It is one of the main reasons you need to make significant changes in both MAF & SD cars.

Raising fuel pressure does not work in a "linear fashion" compared to using larger fuel injectors. Raising fuel pressure tends to have it's least effect at part-throttle and greatest effect in WOT. Thus, if you raised fuel pressure and increased your injector constant (to compensate), you will need to adjust the lower MAF Scalar Tables.

BTW, I somehow recall there was something else you need to change (besides) just the MAF Scalar Tables. It's been a long time since I played with this stuff and I am still recovering from surgery. But I will try and track down some of the other things you will need to adjust. It was over 5 years ago when I did all this. I found this when I ran a "binary compare" program on a variety of $6E BCCs.

Also it seemed almost all of the bins had some variation in the MAF Scalar Tables. We tried running the various MAF Scalar Tables from the bins and found the ARAP the most consistent.

agreed, my car with TPI ran rich stock. I think thats why i gained so much performance by switching to HSR. AFR leaned out and made lots of power over stock.

Hmm, my engine is stock as far as i know (previous owners...) and with the stock $32 bin it ran lean, like pegged at 160 BLM lean. Fuel pressure was good, maybe I can blame old dirty injectors? Used seafoam to clean injectors and switched to $6E and the thing runs rich, very rich until I raised the injector constant from 19.33 to about 21.5! So either the 6E from 32 made the difference or seafoam works great

Or a little of each. Be careful if you have raised your fuel pressue - you may be too high (and fuel pressure greater than 50 psi tends to shorten your fuel pumps life).

The fuelpressure is stock 40/42psi and the injector is Accel 24 Lbs/hr,
injector constant is set to 23.5 on single and doublefire

If I need the change the maf tables I need to change all the tables because if I lower it -1 on 7,99grams then I need to lower the number above it to, and above that, or else it gets a dip ? or ?

MAF screen is removed, thats maybe helping it to run rich.. and another cam.. thats maybe why it runs rich, we tried with a maf with screen in it, it ran sterm 120 and lterm 128 så... maybe We need to lower the MAF tables mecause the screen inside is removed ? Ive read that somewhere that the tables needed to be changed after removing the maf screen inside...

Changing the MAF will affect the sensor reading and thus you should adjust the MAF Tables - preferably with a WB. Removing the screens, hogging out the MAF, and possibly some aftermarket MAFs may all require tweaking of the MAF scalar tables.

I know the MAF tables adjust fuel...but the tables are in Mass air flow sensor volts, and then Grams/sec....

i didnt see anywhere in my datalogging last night a reading for MAF volts. I did see MAF grams/sec monitor. So if i'm abit lean at a certain spot and would like to change the grams/sec....how do you know where to do it at? What MAF voltage?

nevermind the volt, check how much grams/sec the MAF flows when its lean/rich, exaple if it flows 35 grams/sec and runs lean, find the 35 grams in tables and add some on that row, try and change it +0,8 maybe, and se if it runs better there...

cool thanks! i'll have to try that. i figured thats what you'd do but wasnt sure if i was missing something or not. i'm seeing lean during lite throttle acceleration but once i hit my speed that i want to cruise at, the BLMs stabilize to 128 again, so i think my AE needs enriched abit.

Sorry I am looking at the decimal not hex value
IGNORE MY IGNORANCE LOL!
Ed

Are you sure about the scalar values for the ARAP????
Every ARAP I opened with two different definition files in TunerPro has 23 g/s not 17 as you posted ! Are you sure???
Please let me know
Ed

yea, i banged my head for a while trying to multiply by 17 as a scalar, im like what the crap is wrong here?! try it as $17, ohhhhh

i was excited about this thread, maybe somebody can add related info or questions here?

Heres one, don't forget that when you change the scalar, if you go back and look at the Maf tables the value will be different, this is normal, don't panic. One of my buddies called me last night on this, freaking out because he didn't realize that.

Hey guys, exciting time to be into 6E!, i just wanted to say that as this will probably end up in the tuning articles, it is a great example of what a thread SHOULD be. any junior members reading this, this is what TGO is all about, good questions, good answers, and all for general benefit. i'm going over the pages of this as it develops trying to absorb it and i'm happy to be lurking! thanks for the work guys good to see development in maf!

-David

I got a quick easy question about WOT tuning. I wanted to take my car to a dyno and do some runs since i dont have a wideband yet and wanted to see what power i can make.

I think the only things i'll be concerned about with WOT is overall timing thru the rpm range at max LV8 and the fuel that the MAF sensor dumps. They have a wideband air fuel meter so i can make fuel adjustments on that. I hope to shoot for around 13.0 to 1 air fuel but whatever makes best power i will go for that.

Is there anything else i'm overlooking that i should check while i'm on the dyno? Anything else to change?

Actually, before the dyno. Check this table and adjust the values upward:

MASS AIR FLOW vs RPM, maximum value

RBob.

The ARAP i used had thoose values in the Scalar..
I also got 2 ARAP from a friend, and I think maybe he have changed someting in them but the one I gave as an example is the one I use.. So your stock ARAP is different in the MAF SCALAR ??

okay so assume im idling rich at 8.36 gm/sec, i go to maf table 1, go to the 5th row from the bottom(8.36 gm/sec stock ARAP)and add a bit to the gm/sec amount, bumping it up to perhaps, 8.50 gm/sec. sound right? The whole volts thing was keeping me back before.

No, the opposite is what you want to do. The computer "sees" volts. Calcs air, then calcs FUEL from that air. The volts are not changing, and it's rich. So, tell the computer that those volts = less air, and it will calculate less fuel, and lean it out.

ahh yea didn't think it all through, but now i have the procedure! thanks alot, i'm waiting for a cool dry day here to tune my idle, maybe tommorow.

Thanks red, looks like 6e is finnaly getting attention