I have my off throttle/deep vacuum afrs at around 11s-12s, would it be better to leave it that rich or make it leaner, or what should the desired afrs on deep vac be? i noticed the car feels heavy or drones a lil louder with the afr i have

 

I would think it should be much leaner..... If your off throttle it should be between 14.7 and ~17.1.

 

with it being that rich doesn't the exhaust pop alot? sort of like an srt-4

 

yup it used too.. i leaned out my map so i barely get any now. but the pop usually comes with my richer map across the band.. its kinda cool to have the pop sound but gas is expensive lol

 

What are you using to tune your tC?

 

im using hydra..

 

Are you tuning your car yourself? If so I would find a tuner to help.

 

im doing some tuning right now, i was already tuned but im tweaking my map after i got some stuff fixed. I dont have problem changing my fuel maps though, tuning a standalone is so extensive and no way 3-4 hrs on the dyno will get it completely configured so I have to learn stuff myself. Once i get the tune close i will take it to a pro tune

 

Thats good! I did the same thing with the greddy ult. good luck.

 

If the car is in gear but no thottle, you can be as lean as a french model. But if you are just letting the car idle, then anywhere between 15.7 and 16.5 is ok... Leaner then that may cause the sputter. But every car is different so you may be able to take more fuel out or you may have to add fuel.

Do you kno at what point the car is feeling heavy? The louder exhaust may be a result of too much timing retard... Have you tinkered with the vvt.

 

Just so you know Ace, the Unichip is tuned to be extremely lean once throttle is let off - my gauge registers 22.4 which is the max... and staying off throttle, it eventually goes back to 14.4-14.8.

 

I feel the car heavy after letting off throttle together with the louder exhaust drone and a lil jerking at times.. car reads around 11s afr but keeps on bouncing, the bouncing i believe is due to close loop feedback trying to lean out on too rich condition.. i'll try to lean the deep vac afrs then, hopefully i dont have to mess with the spark map and the vvti

 

i thought my emanage tune before is bad coz it does that lol, good to know.. my wideband is as wide as your though.. above 18 it doesnt read. Im gonna do some lean burn tuning soon so i will be aiming on lean vac afrs

 

I dont have much experience with the Hydra but I do have a lil experience with the AEM on the tC and I know the AEM doesnt come programmed with a map for the VVTI. But I would agree with you, lean out the 0 throttle % percent as much as you can then tune from there... Check to see what the ecu or the wideband shows when the car is bucking... I would keep all vacuum readings between 14.0 and 15.0... The highier the rpm the more fuel I would add until reaching 14.0. IMO more fuel then that in vac is not necessary. Having the wideband hooked up to the Hydra (if that capability exists) would help when data logging you runs and you can make a note of the buck and run it back.

Let me know, might not be a big deal.

 

Also are you venting or recirculating?

 

right now i only have wideband gauge but im getting the hydra wideband so i can datalog better and adjust my afr faster, gas is expensive trying to tune on the street lol..

im venting to atmosphere, im not using a maf sensor though

 

What sensors are you using, IAT and a Map? And what are you using to maintain the WOT for the DBW?

 

yup AIT and MAP, hydra uses DBW function of the stock ecu

 

Ok i know the AEM requires the MAF to maintain WOT... But I c now why people love the hydra... I gotta get one just to play with. Get some numbers off the Hydra and we'll see what can be done

 

by "Deep Vac" are you referring to the engine when you are in gear and completely off the gas? Idle/ cruise vac, about -20 psi im running about 15 +/-1

when i down shift (approaching a stop) completely off throttle im at -22psi (i believe this is max on the AEM Tru boost gauge) and my AFR is "---" which is 17++

I never really questioned it.... you're making me think about it now. What would a good tuner (obviously not mine) have for the afr "Goal"