Feed Back Required on AFRs

[lowresolution]

Guys ,
I recently got my car tuned . The car in question has the following specs

Stock 4efte
Td04hl-15t turbo ( from a 2.0l saab )
FCD
FPR ( fuel pressure is set to 53psi )
450cc DSM injectors
AEM UEGO to monitor the AFRs
Apexi AFC
All the supporting mods road runner manifold , boost controller , external wastegate etc etc


The car is tuned on 1.2 bars of boost using the AFC . The AFRs on boost very from 11 - 11.3 , while during cruise the AFRs very in between 13- 16+ range ... ( sometimes the uego reads --- , can anyone tell me what does that mean ??? )

The car runs great and pulls quite harder !

I need some feedback on the AFRs i am getting . Any help/feedback will be greatly appreciated with reps .

 

[350ep70gr]

11-11.3 is AFR on the safe side of things. cruising afr 13-16 is good (4e dont like the very lean cruising tho). --- mean leaner than 18 i think.

Chris

 

[Ted]

Guys ,
I recently got my car tuned . The car in question has the following specs

Stock 4efte
Td04hl-15t turbo ( from a 2.0l saab )
FCD
FPR ( fuel pressure is set to 53psi )
450cc DSM injectors
AEM UEGO to monitor the AFRs
Apexi AFC
All the supporting mods road runner manifold , boost controller , external wastegate etc etc


The car is tuned on 1.2 bars of boost using the AFC . The AFRs on boost very from 11 - 11.3 , while during cruise the AFRs very in between 13- 16+ range ... ( sometimes the uego reads --- , can anyone tell me what does that mean ??? )

The car runs great and pulls quite harder !

I need some feedback on the AFRs i am getting . Any help/feedback will be greatly appreciated with reps .

what standard of fuel do you guys have over there? have you checked for detonation too?

 

[lowresolution]

Using 93 Octane here . Which is the best quality of fuel available over . I am assuming that if the UEGO displays --- it means that it has gone extremely lean . rite ?

Also there are no signs of detonation or knock .

Should i richen things up a bit ? lets say up the FPR from 53 to 57-58 may be ? and then check the readings over at the a/f gauge ?

 

[Ted]

Using 93 Octane here . Which is the best quality of fuel available over . I am assuming that if the UEGO displays --- it means that it has gone extremely lean . rite ?

Also there are no signs of detonation or knock .

Should i richen things up a bit ? lets say up the FPR from 53 to 57-58 may be ? and then check the readings over at the a/f gauge ?

93 octane aint great but not as bad as some places. if theres no knock then its ok i would say, just get the best fuel available at all times.

 

[hardcoreep]

The lower the number the richer the car, therefore 11.3 is still very rich. most EPs run in the 10s. So the statement is correct that 11 is a very safe number. On the other end 16 again is a very safe number. The bottomline, your car was tuned with very conservative numbers to stop you from blowing it up probably or ensuring the tuner doesn't have to deal with you should the engine fail as it wouldn't be the fault of his tuning.

Leaner = more power/greater risk
Rich = less power/lower risk

 

[JasonGlanza]

14.5-15.2 range afrs are best for an 4efte during criusing or idle condition, dnt like to be much leaner. on boost ur quite safe at low 11s

 

[lowresolution]

@hardcoreep
thanks mate for such a detailed reply helped alot !

@JasonGlanza
The A/F gauge sometimes reads --- and the car stalls if i quickly change to 2nd gear at around 2000 RPM

like for e.g m driving around city in 3rd gear and see a small pot hole , i changed the gear to 2nd and slowly push the car forwards to slow down the momentum a bit . In this scenario the A/F gauge shows --- and i get the feeling that the car hesitated a bit ...

is this normal ? or my feelings are just feelings

 

[lowresolution]

@Ted@CCM
there is only one place where 95 octane is available ..but its quite far . That is why i opted for 93 octane ( still better then the 89 octane which is sold at 99% of the pumps here )

 

[JasonGlanza]

when the gauge read --- its above 18 afr, it happens when you engine brake or when in any gear but without any throttle, its normal to do that mate, dnt wry! important that on boost its fine and on idle or cruising speed its between mid 14s to low 15s.

 

[lowresolution]

@jason
Thanks a bunch mate ! Got my answer ...

long live this forum and its members

 

[haydn28]

Guys ,
I recently got my car tuned . The car in question has the following specs

Stock 4efte
Td04hl-15t turbo ( from a 2.0l saab )
FCD
FPR ( fuel pressure is set to 53psi )
450cc DSM injectors
AEM UEGO to monitor the AFRs
Apexi AFC
All the supporting mods road runner manifold , boost controller , external wastegate etc etc


The car is tuned on 1.2 bars of boost using the AFC . The AFRs on boost very from 11 - 11.3 , while during cruise the AFRs very in between 13- 16+ range ... ( sometimes the uego reads --- , can anyone tell me what does that mean ??? )

The car runs great and pulls quite harder !

I need some feedback on the AFRs i am getting . Any help/feedback will be greatly appreciated with reps .

the car is tuned good ,but 11.0- 11.3 i would use on 95 RON ,but on 93 RON u have to compensate for the leaner cylinders (3 & 4) , the car wont show knock at all right now , but its really heat that breaks ringlands so on 93 RON tune it a little richer like 10.8:1/10.7:1, and keep timing on the dizzy at 10deg

on higher boost ive seen my starlet (300whp+ on 95 RON) gain power richer due to
1 latent heat or vaporisation taking heat from the intake
2 more complete burn for all the compressed air.
3 more fuel keeps det at bay , since ur using a piggy back, richer keeps trace knock 10-15% away and prevents timing retard on the stock ecu

japenese tuners like tomei/hks tune to 10.8:1 at high boost for the same reasons

 

[gorganl2000]

your base fuel pressure seems rather high at 53 psi

and your car shoud not be stalling when you change gear unless your revs are too low for the particular gear you select

 

[hardcoreep]

Actually the Japanese ECUs run that rich because of the timing. Should you opt to run 100 octane you'll notice the mixture leans out. The reason I got my eManage for my Access is because I needed to trim fuel. My afr here in Jamaica on CT9 running 13psi was 22:1 to 10.7:1. The safest afr here for maximum power is 12:1 and when have 93RON. My Access with a td04-11b tacked on self-adjusted to a wonderful 12:1 @ 5psi across the board. In case you're wondering, more air into the engine to burn off the extra fuel. It drove fine for next to forever. Running at 10:1, unless you have some big turbo is just a waste of fuel and probably will lead to long term engine damage as the extra fuel can either wash off the oil on the cylinders or reduce the viscosity of the oil.

As for the shutting off during shifting, that's easy. At 53psi you're flooding the engine during transitional response. I'd say adjust it down, but you're going to have to probably retune if you do that because fuel delivery volume will have changed.