zrater

i hit about 62 grams at wot and thats it, why so low on a stock 02 z.. thanks

jimmyblue

iTrader: (11)

0.8 g/cyl is about normal but it's all subject to your VE and MAF
fidelity, what airflow & air mass you calculate. Tuning to an AFR
result, with an existing short fuel error, is one way to end up at
a clean running tune that simply has a wrong airflow scaling (two
wrongs make a right, style).

BobDoLe

iTrader: (11)

i also suggest cleaning the maf. there's a few threads you can search for about that. basically use electrical cleaner (???) and spray it on the wires. you could possibly use a q-tip and VERY CAREFULLY/GENTLY (they break easily) wipe the dirty side of the wires.

in my 99 with lid, catback and stock ls1 intake i was seeing about .68-.76.
after throwing on the ls6 intake it was up past .8, but that could have something to do with the bigger stock cam.

macca_779

Just an FYI and probably wont relate to this car because its relatively stock. But I do know of cases where tuners will fudge the IFR table to give extra range in the timing tables. How this works is by altering the IFR and subsequently having to lower the VE values to dial in fuel you trick the engine into thinking that its getting less dynamic air than it actually is. For Boost this can aid the tuner as you won't bottom out at 1.2g/cyl quite so early or at all if your really aggressive on it.

2002_Z28_Six_Speed

iTrader: (19)

A stock car shouldn't see over .68/cylinder.

zrater

thanks all,, all i did to the stock program was pull some timing to get
rid of det and change shift points to 5700-5800-5800, and open
cut out and slp lid and air hog ...

SSpdDmon

iTrader: (10)

I would expect to see no more than .68~.76 grams/cyl from 3K RPM on up at WOT on a near stock f-body. As altitude rises, that number will fall. Being you're at moderately low elevation, I'd suggest there's something wrong with your MAF. If cleaning it doesn't help, try swapping with a known "good" MAF.

Frost

iTrader: (45)

I dunno, I'd say that's pretty close to what I see here in VA from them.

2002_Z28_Six_Speed

iTrader: (19)

By no means do I want to insult you. That is far from it -- as I know you are a good tuner

But isn't .68 to .76 a really big gap?

Frost

iTrader: (45)

It's 3 rows in the HO LO tables

zrater

does shift points make a diff, i got them down from stock #s

SSpdDmon

iTrader: (10)

Like I said - it depends on DA. In the winter 30~40 degree weather, he may see up to .76 peak. In the summer, not so much. Plus, you don't see the same grams/cyl. at 3K that you see at peak torque. If you log the commanded spark path on the map, you get a curve similar to what you would get off a dyno chart...as if it was laid on it's side over top of the timing map.

BLK02WS6

iTrader: (2)

Same here...

zrater

would lowering the timing play a role in this or more fuel in this case.
by lowering the maf or raising it does that kinda give a false readings
in the gpc map. somtimes i see like -12% long trim at 55 .. and at
wot it goes down to 8% both banks smells fat!! will a
air pump shut down have anything to do with this. the car runs 13.5 @106.

SSpdDmon

iTrader: (10)

Yes - if you alter the MAF curve, it'll affect the grams/cyl. calculation in a directly proportional fashion (up is more, down is less). The cars will run fat from the factory. If you're running no cats and no AIR, you'll smell it. But, that shouldn't affect your AFR - UNLESS you have an air leak (i.e. measured air is escaping before it reaches the cylinders). Pulling timing won't affect it as much IMO. Sounds like you need to evaluate the mechanicals before you point to the tune on a mostly stock car.

With regards to your tune AFTER you make sure the mechanicals are working right - I wouldn't alter the MAF or VE if I were you given the car is mostly stock. Just lean out the PE some. As for timing, you can add a little in as long as you don't get any knock retard. But, I wouldn't mess around with timing unless I was on a dyno. No reason to add timing if you can't justify it as a proven gain.

zrater

that all make sense, and yes it does smell on a roll then wot, the pe is
set at 1.20 3000 up to 5000 then bump to 1.30afr to 7000 and it seems fat but not upper rpms. i think wide
band was down at 11.8-13 afr. thanks very much everyone !!