Advice on tuning AE w/WB (ZT-2)

[91chevZ71]

How rich do you want the AFR to go when you're tuning AE? Not stomping on it, just going from OD to 3rd at 65, 3rd to 2nd and 30, normal acceleration kind of stuff. What's the 'rule of thumb' on AFR's for AE?

[HaulnA$$]

How rich do you want the AFR to go when you're tuning AE? Not stomping on it, just going from OD to 3rd at 65, 3rd to 2nd and 30, normal acceleration kind of stuff. What's the 'rule of thumb' on AFR's for AE?There is no 'rule of thumb'. The amount of AE required depends on a lot of factors. Obviously the AE AFR needs to be richer than the normal desired AFR at cruise or WOT since the whole point is to enrich the mixture, but how much is dependant on what you're trying to get to accellerate. Too little AE and you get lean pops. Too much and bogs occur. Factors like HP to weight ratio and gearing play huge part AFR wise. A light car with tall gears will need much less AE than a heavy truck with small gears. The amount of fuel required to reach that magic AE AFR can also vary greatly between wet (TBI) and dry (PFI) flow systems. Datalogging your WBO2 is your best tool to dial-in AE. 60 foot times help with WOT AE. HTH

[91chevZ71]

OK, thanks Haulin. I gather since my AFR's ar still pretty rich (low 13's) that I can reduce more. The 4.56 gears are helping, I know... Man, I could really stomp on it. I've reduced AE tons and it is still rich on tip-in. 90pph inj's are awesome. good stuff

[91chevZ71]

Well, I tried a new TPS AE scheme today and it has yielded pretty decent results. The truck really likes the increase in TPS AE. The CTS table still needs some refining, as I have a slight bog when the engine is first started and CTS at 8 deg celsius. The 90 pph inj's at 15 psi are absolutely to blame for the crazy AE tables...they let out a bunch of fuel on the slightest command, or so that's what I'm realizing. The tables look small, but the scale goes up to 15 ms. To compare, my injectors at WOT on the dyno are running about 4.8 ms. I also have a super heated manifold (GMPP TBI vortec)


http://i184.photobucket.com/albums/x246/bmd2_colo/TPSAE.jpg
http://i184.photobucket.com/albums/x246/bmd2_colo/MAPAE.jpg
http://i184.photobucket.com/albums/x246/bmd2_colo/CTSAE.jpg

[oldred95]

Damn thats low. I raised mine some more today and richened the CTS table a little at the cooler temps to fix my cold take off lean bog after shifts. Chris said the injectors will make some difference but he said that AE is taken care of in one of two places, the AE tables or the VE tables. My guess is depending on where they were initially set and dictated how your VE tables worked out and you ended up with your VE's taking care of most of your AE. Also a little tid bit of info that might do you some good. Zero out the 0% throttle cells because you don't need AE at 0% throttle. I learned that the hard way when I turned my AE way up and had something like 600 in both 0% cells and it wouldn't even idle it was so rich.

[91chevZ71]

thanks oldred.

Having a slightly rich VE does help on lessening the AE. noticed that
It is a fine line for me...if it's too little, the AFR's jump to 16 right after tip-in, too much, she dives to 13 and bogs.

[91chevZ71]

I need more MAP AE. I went for a spirited drive; when it shifts, it has a soft spot which I think is a lean surge then it goes

[oldred95]

Thought I'd enlighten you on something I learned last night. I've always had this initial bog in power when I step on it even with AE set pretty close. Asked fast305 what the deal was and he told me to look at my spark table at the 400 rpm and 100KPA cell and see what was there. From a dead stop if I mashed on it I was only getting between 8-10 degrees spark advance depending on what cell it landed in and then the advance ramped up fairly quickly which explains the torque management light take off I was getting. I set the 400 rpm and 100KPA cell to 14 degrees and worked off of that scaling it up gradually until it fit well with the rest of the table. It will be a few days before I get to test it but I think this is going to make a big difference. If you are having a similar bog on WOT take off you might want to try this.

http://img.photobucket.com/albums/v604/oldred95/sparkadvance.jpg

[91chevZ71]

EBL has launch mode SA, maybe I could crank it up a couple degrees. thanks oldred

[oldred95]

EBL has launch mode SA, maybe I could crank it up a couple degrees. thanks oldred
:whatever: Sounds complicated to me.


What octane are you running? I was watching horse power TV and they did a dyno test on this Fitch fuel enchancing hodis and it actually made pretty significant differences in fuel used. They used a stock LS7 427 vette engine on 93 octane as a base line and and has x amount of power and a fuel rate in gallons per hour of 20.16 I believe. Then the added the Fitch fuel deal still on the same 93 octane and got a couple hp more but about half a gallon less per hour fuel rate. Then they switched to 89 octane and lost some power but had a 23.xx per gallon fuel rate. They added the Fitch fuel deal and didn't gain any power but dropped the fuel rate down to 20.xx per hour. It ended up saving a little over 2.5 gallons per hour on 89 octane. Basically they proved 87 and even 89 are trash for fuel. I think I may bite the bullet and start running 91 octane since thats the best we've got around here.

[91chevZ71]

I've always ran 91. Launch mode isn't too complicated, kinda like AE for spark advance.
http://i184.photobucket.com/albums/x246/bmd2_colo/launch.jpg

[oldred95]

So you've got around 10 degrees advance then. You might try a little more just for the hell of it.

[91chevZ71]

10 degrees? Ive only got what is says in the table when launch mode is happening (plus normal SA table). where are you getting that? just curious

my delta TPS enable for launch mode is only 1.18 percent, so I get it pretty much every time

[oldred95]

10 degrees? Ive only got what is says in the table when launch mode is happening (plus normal SA table). where are you getting that? just curious

my delta TPS enable for launch mode is only 1.18 percent, so I get it pretty much every time
Your normal 8.xx in the spark table plus your launch table.

[91chevZ71]

well, I tried some new numbers today. I copied the AE numbers from BRDW.bin(TBI L31) with really good results.

Thanks Fast