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Discussion Starter · #1 ·
I just installed a Donaldson on my two day old 02 and now I read on the forum under search section that Donaldsons do not work well with 02's some said pig rich and some said super lean...I do not understand, Haltech and others claim there filters rock on 02's why doesn't the Blackwing, Haltech uses the same filter media as Donaldson. So what should I do? Take the filter off today asap and reinstall the stock setup? After I installed the Donaldson the car ran awesome...Please need some info and help I do not want to screw up a brand new 02. Thanks in advance.
 

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I also read the same info, that is why I went with the halltech T-1 sidewinder. I didn't know how true it was, but I didn't want to take a chance.:cheers:
 

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ZO6ROX said:
I just installed a Donaldson on my two day old 02 and now I read on the forum under search section that Donaldsons do not work well with 02's some said pig rich and some said super lean...I do not understand, Haltech and others claim there filters rock on 02's why doesn't the Blackwing, Haltech uses the same filter media as Donaldson. So what should I do? Take the filter off today asap and reinstall the stock setup? After I installed the Donaldson the car ran awesome...Please need some info and help I do not want to screw up a brand new 02. Thanks in advance.
Does the Blackwing come with a new Air Bridge like the T-1?
 

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I have a donaldson on my 02 and it works great. Nice increase in SOTP and no surging. I also put a Halltech airbridge on at the same time so I don't know if that made any difference richness or leanness. I just know it runs great.
 

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Discussion Starter · #5 ·
That is exactly my point, the haltech t-1 breaths just as good as the blackwing and if you go with the haltech air bridge well that just increases the air flow that much more...and halltech has not reported any wierd conditions with his T-1...so what is the story with modded air intakes for the 02. Should you stay stock if you do not want to go with a MAFT, because my dealer will not honor my warranty if I install a MAFT...Has anybody put a AutoTap on a 02 with after market intake and checked WOT for the fuel trims. I really think that the pcm will learn the increased air flow and will correct the AFR. If the car really was getting a super lean fuel trim then I think I would be getting a code on the DIC, that lean of a condition would have to set something off in the pcm if it cannot correct for the increase air flow. And if the car was running rich at WOT then the damn thing would surge like a mother or flat spot.
 

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This one has me puzzled also. After breaking in my '02 Z, I installed my DBW with stock air inlet tube. I immediately noticed a louder (more muscle car sounding) engine note. BTW, I already had Corsa Indy Pace Car exhaust on the car. So far, no problems at all. Unfortunately, the Vet is stored for the winter, so I just wait and see what develps before I get back on the road.

If I even suspect the DBW causes problems of any kind, I go back to stock....no reason to jeopardize my baby!

Zippy :z: :z:
 

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Pig rich

Why rich?
Seems like the opposite would be true right? What happens is when you add an intake mod (more air, remember engines are an air pump) which causes a lean condition (more air, less fuel), the O2 sensors re-trim the stoichiometric seeking (1-19 cells) back to 14.6:1 by adding pulse width to the injectors. This additional fuel is recorded in the fuel trim tables and added in, in addition to the WOT Fuel Enrichment code (fuel cell 22) which was designed to provide 12.6:1 ratios (in general). WOT is not subject to the O2 sensors since it is Open Loop, but the computer 'Snapshots' the added fuel percentage of the previous trim prior to WOT. You may see a/f ratios in the 10s or 11s, which means your WOT throttle is losing power bigtime.
By adding this particular "Snapshot" of the previous trim to WOT, your injectors will add TOO much fuel, even though they are close to 100% duty cycle.
The PCM will move from cell to cell under varying conditions.
There are 22 Fuel Cells, and are as follows:
1-19 – used to update fuel trims
20 – Idle Cell
21 – Deceleration Cell
22 – WOT (Power Enrichment mode)
:cheers:
 

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Discussion Starter · #8 ·
Thanks for the info....so I will lose hp at wot with the donaldson unless I go to a MAFT, which I will not do..back to stock I guess.
 

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I think I might be able to kinda solve this. I'm getting the 02 dyno'd on the 23rd. Perhaps I can make my 3 runs, go install the donaldson, run it a few miles to allow the computer to relearn, and then redyno.

Any comments on how long it should take the computer to relearn?

-jbl
 

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Re-learn time

It takes about 1 hour of driving to relearn. To get everything re-learned, you should alternate between normal driving and hard (some WOT) driving. A little more than an hour if you want to be sure.

Actually, the algorithm checks the STFTs every 10 minutes and updates the LTFT if necessary. A number of these cycles are needed to settle on stable values.
 

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JasonBrent said:
I think I might be able to kinda solve this. I'm getting the 02 dyno'd on the 23rd. Perhaps I can make my 3 runs, go install the donaldson, run it a few miles to allow the computer to relearn, and then redyno.

Any comments on how long it should take the computer to relearn?

-jbl
Please keep me informed after your dyno results. I have a Donaldson also on my 02 and am not sure what to do.
thanks
Rocky
 

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At Saturday's dyno day a 2002 Z06 with the Donaldson turned 357 HP. A friend's pure stock had 356 and my wife's pure stock was 354, another friend's was 347. All four of these, like many others were running somewhat rich, around 12.0 at top end.

The one with the Donaldson had about 3,600 miles, the others were about 2,700, 2,400, and 600 respectively.
 

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Re: Pig rich

fyrcaptain said:
.............the O2 sensors re-trim the stoichiometric seeking (1-19 cells) back to 14.6:1 by adding pulse width to the injectors. This additional fuel is recorded in the fuel trim tables and added in, in addition to the WOT Fuel Enrichment code (fuel cell 22) which was designed to provide 12.6:1 ratios (in general). WOT is not subject to the O2 sensors since it is Open Loop............
Is cell 22 a fixed value or is it updated through an algorithm?
 

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When going to WOT or Power Enrichment Mode. The PCM does several things.
It no longer is concerned with maintaining economical or environmental operations. It freezes the fuel trim adjustments, stops monitoring the O2 sensors, and looks briefly where it was at in the “closed loop mode”.
It then starts to rely almost exclusively on the MAF sensor input for proper a/f adjustment.
Here is where we are most concerned. Since we have modified our stock MAF, all the conditions of unmetered air, decreased air velocity, etc., that we created, cause the system to go, and stay lean, in the power enrichment mode.
To solve this problem, we need to increase the injector flow rate. To do this, we can either have custom PCM programming done, which modifies the a/f tables in the PCM to accommodate the difference in airflow. Or we can modify the signal before it enters the PCM for processing by tricking the PCM into perceiving there is a greater or lesser load being reported.
 

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Z06ROX what is the reason the dealer won't honor warranty with MAFT.I just bought the t-1 composite for $299, does'nt it have a MAFT?Will I have warranty issues.If so,I guess I'll have an intake for sale cheap.
 

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Re: Cell 22

fyrcaptain said:
To do this, we can either have custom PCM programming done, which modifies the a/f tables in the PCM to accommodate the difference in airflow. Or we can modify the signal before it enters the PCM for processing by tricking the PCM into perceiving there is a greater or lesser load being reported.
frycaptain,
This is almost word for word what the guys @ DRM told me when I called them about the BW problem. They had dynoed a '02 with the BW installed and it showed a 20hp loss from stock above 5800rpm. After a PCM reprogram, it had a 20hp gain from stock with the BW the only mod. The guy @ DRM said that all the recalibration did was keep the injectors from going full static on the big end with the increased air flow. I'm just like Z06ROX in that I had the BW before I knew there was a problem with them on the '02. I'm going to have my computer done in the spring when I put my headers on and install my 30lb injectors.
 

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Discussion Starter · #17 ·
No, the T-1 is a intake the MAFT(translator) is a plug and play device that enables you to adjust A/F and trick the PCM. Go into search and you will see tons of info on this subject. Haltech does not sell a MAFT he sell a expensive calibrator that does about the samething.(Jim correct me if I am wrong concering your afr).From what I am understanding you should look into it so your car will not go lean at WOT. I went back to stock till I can afford a Power Loader 2, then I will not worry about warranty...dealer will have no clue you are using it.
 

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Re: Re: Cell 22

Z06 Tom said:

I'm going to have my computer done in the spring when I put my headers on and install my 30lb injectors.
A MAFT might be cheaper that a re-program (I've heard $400)
With the #30's and a MAFT, here's what happens:

If you have 30# injectors, set your base to 0 on the MAFT. Most folks think that you should lean out the base a little bit because the injectors are so much bigger, but this defeats the purpose of the #30's. I think the PCM sets the LTFT's by the O2 sensors only. So when you lean it out, the PCM pulls fuel out, but then the O2 sensors read a lean condition and inject more fuel.
The MAFT works the opposite of the way you think that it would. If you get a positive number on your scanner, then you need to richen the mixture on the MAFT, and if you get a negative number, you need to lean it out. Set the MAFT to 0, put about 100 miles of normal driving on it (whatever that may be ) and check it again.
The dyno is only used to adjust WOT settings, since you spend most of the time at WOT on the dyno, this is perfect. You want your LTFT's at 0 because this gives you the perfect starting point. If you can watch your AFR on the dyno, you'll notice that it is always in the mid 14's at part throttle. No matter what you have your MAFT set to, it will always read mid 14's (if possible). That's what the PCM is programmed to do in closed loop (part throttle), achieve a 14.7:1 AFR. When it can’t, or when it has to make too many changes to get to that ratio is when the "Check Engine" light comes on. When you go to open loop (WOT) the PCM ignores the O2 sensors and goes to the fuel and timing tables that it learned at part throttle. The PCM still reads the MAF at WOT which is why the Translator works so well. However, with your LTFT's at 0, it will still run extremely rich at WOT. Once you get your LTFT's to 0, then put it on the dyno with a wide band O2 sensor.
The factory O2 sensors have a reputation for being very inaccurate, so don't rely on them alone. With your LTFT's at 0 and your MAFT set to 0 WOT, your AFR will probably go off the scale for part of your first pull (meaning below 10.0 AFR). Keep leaning it out at WOT until your AFR gets to the high 12 to low 13 range, or until power falls off. Also, try to keep your pulls consistent. Meaning, keep your coolant temps below 200 degrees at the start of each pull, make each pull from the same RPM to the same RPM, etc. etc. Since the PCM doesn't "read" the O2 sensors at WOT, and since you don't spend most of the time driving your car at WOT, these settings shouldn't really change over time. Unless, of course, you make changes to your motor.

:cheers:
 
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