JWT ECU + Z32 MAF + 370cc's - lean?
 

Today I was messing aorund with my LM-1 and decided to set my AFC back to "0" for everything and measure what the JWT by itself pulls.

I was 14.0 pretty much all the way to redline!

My first thought was that maybe the ECU learned my old AFC settings (had it set to richen 15%).
I have the AFC High-Throttle point set to 40%. I thought that over 40% was basically WOT and the ECU didn't "learn" above that?

I then went and reset the ECU completely. (Using both my NProbe and the screwdriver method to be sure)
Same readings - still 14.0:1 across the band....weird.


Settings:
Sensor Type: 02 02
Car Type: 6 cyl up
Thr Points: Low, 39% - High, 40%

Of course - I reset the AFC to the higher settings and am back to aorund 12.0:1 with it going to 11.5:1 at redline.

In other news I just did a compression test after 20k of pushing 14.5 PSI...

#1 - 176
#2 - 177
#3 - 183
#4 - 175
#5 - 184
#6 - 175

Had you never see JWT's AFR without AFC corrections?

Wow, that is lean. No exhaust leaks before you wide band bung?

The ECU won't "learn" anything the AFC does.

Try re-calibrating the LM-1.

Go down a huge hill in a low gear, high rpms and let the engine hold you back down the hill. Supposidly it will fill your exhaust with fresh air. Calibrate on your way down :)

-matt

When I first installed the EEPROM I only switched from the A32 to Z32 MAF and EEPROM. - with the A32 MAF I had it richening at 4500 to try to keep the MAFs limitations from leaning me out up top too much. So no - I haven't touched the AFC since then since it looked like the Z32 MAF gave the same A/F (12.0-12.5:1, just not leaning up top). Actually hadn't thought of it until I Dynoed yesterday.

Vacuum is perfect, compression is perfect, etc, etc....can't find a reason it would be lean except that the AFC being set to richen somehow made the ECU lean itself due to the ECU deciding the AFC settings were "normal" and tuned to it. :gotme:

But resetting the ECU should erase that anyway I would think. I know that when I ran at the Dyno a year ago and reset the A32 version of this ECU it dropped the A/F WAY down until about 60 miles later when everything evened out to normal. I don't remember what my AFC settings were then. I think I was set to richen up top then also.

I free-air calibrated it about a month ago by removing the O2 Sensor completely and calibrating.

Also - I Dynoed yesterday - the readings vs the Dyno O2 were dead on. (with AFC richening it up to about 12.0-12.5:1).
<got 356hp even with some spark blowout happening up top - should do even better next time I run now that I've fixed that.....> :D

And I show a perfect 14.7:1 when cruising at partial throttle on the freeway. Also 14.7 at idle as well.

So I'm very confident the LM-1 is dead on.
Just to be sure I'll calibrate again tomorrow after it's been sitting overnight and take the O2 Sensor out agian before calibrating to ensure the 100% best possible reading.

I'll report back then.

It's just the tune. The AFC is not gonna cause any problems

JWT Tune = Sucks :wall:

Emanage Ultimate = :doublethu

AGREE.......

You get it in :D

No not yet :wall:

Yeah - didn't think the AFC was part of the problem....
I suppose in theory it could be a byproduct of running the Z32 MAF on the charged side....but nah - JWT probably just sucks.

Recalibrated again this morning (free-air) and still get the same readings.

But since I've already spent this much and spent over a YEAR trying to get the JWT to work with the Z32 MAF.....I'm going to wait a while for the EU. Actually I plan on selling the S/C and building a Turbo kit. When I do that I'll likely switch to the EU.

Right now wife quit working and kid a few months away....no more toys for the Max.... :(

If it wasn't for the AFC I'd be in seriously dangerous waters with this ECU.

JWT says that you can't use the AFC with their ECU as it will blow your engine. :rolleyes:
Other way around JWT...proven wrong once again....

I don't think it's a big deal to have to use AFC corrections, but it's just the fact that you shouldn't have to. Also, if the ECU did what it was supposed to do then you could have an extra $200 and get rid of the SAFC.

Exactly...

Seems like another case of JWT-POS-FI-ECU syndrome. That sucks man, bummer. Nice numbers you put down though :D

Yhea, kinda skipped over that. 356whp, nice! Got graph?

Not really a bummer - just an observation - since I already have an AFC - it doesn't matter a whole lot to me. Might to others tho - so I posted it.

As for the Dyno last weekend.....
I don't count it as a real run due to the spark blowout. (when you see the graph you'll be like "wow - that's definately blowout".)
I'm sure after fixing my gapping I'm getting even better numbers...just on a test drive after fixing it I was amazed at the difference in feel......I'll find out officially in a couple of weeks. I don't like to guess too much but I'm confident I'm hitting 360hp at minimum.

My password to my hosting site is not working and the guy that owns the server doesn't seem to be around. I'll post in a few days after I get a hold of him.

Here's the Dyno when I ran with the AFC set to 0% everywhere.

http://www.cyberhub.net/dyno/JWTAirFuel1.jpg

I was wondering what kind of fuel pressure do you see at idle/WOT? I know that in my se-r a 2psi difference will cause the A/F ratio to shift 1 point up or down. For example with FP at 43psi with vac off, I got a top end A/F of 13.0. With it set at 45psi I now get 12.0 A/F up top. At your boost of 14.5psi you should see around 57-58psi fuel pressure. If its less than that try bumping the FP up 2-3psi and I bet your AFR falls back to where you need it.

The JWT ECU was programmed for 3 bar (43.5PSI) - I am running exactly that.

At WOT I'm seeing around 65PSI.
Can't be sure because the car is too freaking fast to take my eyes off the road to look over at the gauge exactly at redline. :D