somebody answer this A/F question please
11-23-05, 11:04 AM
#16
Thanks for the offer but I left the car in Atlanta and will deal with it next week. as an FYI its a 1uz with 8:1 compression and currently 8psi of boost. It was fine on Saturday when I picked up the car sometghing has happened to make it run lean in the last few days. Like I said the best guess is the fuel pump is tired. We did richen up the settings but we only got about a 1/2 point change in the AF. So they think that the fuel pump just isnt keeping up with the demand. I had one guy tell me that he thouth it may be the drop in air temp making it run lean but I am doubtful of that.
11-23-05, 11:11 PM
#17
I think you are good with that reading under partial throttle. Under closed loop, that is about what I get under partial throttle. But at WOT, I get 11.5 when in open loop.
11-24-05, 08:14 AM
#18
Lexus Fanatic
iTrader: (20)
I think you know this morris but just to be sure... the LOWER the A/F number the RICHER it is so you want a lower number at WOT to be safe than when on part throttle.
I think mine's about 12 in normal driving and about 14 at WOT. I think when I went for dyno tuning at Battleground they found the car was about 16 at WOT so they brought it down to 14 to run less rich and gain power. Lexus tunes the car very conservatively so as to make detonation extremely unlikely.
I think mine's about 12 in normal driving and about 14 at WOT. I think when I went for dyno tuning at Battleground they found the car was about 16 at WOT so they brought it down to 14 to run less rich and gain power. Lexus tunes the car very conservatively so as to make detonation extremely unlikely.
11-24-05, 10:03 AM
#19
Originally Posted by bitkahuna
I think you know this morris but just to be sure... the LOWER the A/F number the RICHER it is so you want a lower number at WOT to be safe than when on part throttle.
I think mine's about 12 in normal driving and about 14 at WOT. I think when I went for dyno tuning at Battleground they found the car was about 16 at WOT so they brought it down to 14 to run less rich and gain power. Lexus tunes the car very conservatively so as to make detonation extremely unlikely.
I think mine's about 12 in normal driving and about 14 at WOT. I think when I went for dyno tuning at Battleground they found the car was about 16 at WOT so they brought it down to 14 to run less rich and gain power. Lexus tunes the car very conservatively so as to make detonation extremely unlikely.
Thanks Paul you mean they made it more rich by bringing it down to 14 from 16 right?
And should that read that it is at 14 during normal driving and goes to 12 at WOT?
But any way I'm just excited to have the car back after a year. We'll get the fine tuninng worked out hopefully, I still have enough change left to do it.
I'm only at 8 psi and it is real strong I cant even imagine what it will be like at 15psi.
11-24-05, 10:50 PM
#22
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Originally Posted by morris
Thanks We are on the same page.
your fine morris
How's the car running? And as long as your BELOW 15:1 under partial throttle you should be fine.
You may want to do some 40%-50% throttle pulls next time on the dyno to double check. Turbos make boost at part throttle, so you don't want to come up short during partial throttle with lots of advanced timing.
What is the max timing your @ at peak TQ?
11-25-05, 03:19 PM
#23
You should have upgraded the fuel pump to begin with. If you have more fuel you can always pull it out where it's not needed with proper tuning..if it's not there.. you cant add it.
The 40-50% thottle and fueling under part throttle all goes back to the original problem I tried to discuss on Morris' other thread.. The SAFC2 is TPS based on switching the fuel maps. Not Load based..in other words giving the fuel where it needs it only. Turbos do not make linear boost the same at every throttle position in every gear.. superchargers, especially centrifugal blowers..do for the most part. Do some research, convert the SAFC2 to a load based switchover instead of TPS based and you'll have much more precise..safe..tuning.
Either way.. good luck
The 40-50% thottle and fueling under part throttle all goes back to the original problem I tried to discuss on Morris' other thread.. The SAFC2 is TPS based on switching the fuel maps. Not Load based..in other words giving the fuel where it needs it only. Turbos do not make linear boost the same at every throttle position in every gear.. superchargers, especially centrifugal blowers..do for the most part. Do some research, convert the SAFC2 to a load based switchover instead of TPS based and you'll have much more precise..safe..tuning.
Either way.. good luck
11-25-05, 06:34 PM
#24
Lexus Fanatic
iTrader: (20)
Originally Posted by morris
Thanks Paul you mean they made it more rich by bringing it down to 14 from 16 right?
And should that read that it is at 14 during normal driving and goes to 12 at WOT?
But any way I'm just excited to have the car back after a year. We'll get the fine tuninng worked out hopefully, I still have enough change left to do it.
I'm only at 8 psi and it is real strong I cant even imagine what it will be like at 15psi.
And should that read that it is at 14 during normal driving and goes to 12 at WOT?
But any way I'm just excited to have the car back after a year. We'll get the fine tuninng worked out hopefully, I still have enough change left to do it.
I'm only at 8 psi and it is real strong I cant even imagine what it will be like at 15psi.
I'll have to go look at the dyno sheet if I can find it.
Anyway, looks like I'm selling my car this Sunday!
11-27-05, 11:04 AM
#25
I didnt want you guys to think I was ignoring you. Everyone has been quite helpful.
Bags, I dont know what the timing is set at off hand. I do know that they had it hooked up to some sort of scantool and were looking for any indications of knock and that so far we are okay. I also have the knock sensor hooked up on the SAFC and it still reads 0. Except for me knowing that it runs lean the car has been running nicely, thanks for asking. Hopefully I will see you at the next Seloc Meet.
Epik about the fuel pump, we new that we may need to upgrade it but we wanted to make sure that it was going to be an issue before I incurred the cost. The only way we could know if it was going to be an issue was to give it a shot.
I have looked into the load based SAFC modification and it interests me a great deal. I found several links for those of you that are unfamilliar with it here is one. http://www.2gnt.com/www/corbin/foolafc.html
It doesnt seem expensive, 35.00 in parts, but self tuning the SAFC is not sometihng I am ready to undertake myself. Too much money spent for an amateur like me to risk messing it up. I'll look into is some more.
Good luck on the sale and the buisness Bit.
Bags, I dont know what the timing is set at off hand. I do know that they had it hooked up to some sort of scantool and were looking for any indications of knock and that so far we are okay. I also have the knock sensor hooked up on the SAFC and it still reads 0. Except for me knowing that it runs lean the car has been running nicely, thanks for asking. Hopefully I will see you at the next Seloc Meet.
Epik about the fuel pump, we new that we may need to upgrade it but we wanted to make sure that it was going to be an issue before I incurred the cost. The only way we could know if it was going to be an issue was to give it a shot.
I have looked into the load based SAFC modification and it interests me a great deal. I found several links for those of you that are unfamilliar with it here is one. http://www.2gnt.com/www/corbin/foolafc.html
It doesnt seem expensive, 35.00 in parts, but self tuning the SAFC is not sometihng I am ready to undertake myself. Too much money spent for an amateur like me to risk messing it up. I'll look into is some more.
Good luck on the sale and the buisness Bit.
11-27-05, 06:19 PM
#27
Not many will agree with this but..... You do need a upgraged fuel pump AND a adjustable Fuel pressure regulator. The upgraded fuel pump will not be consistant without the Adjustable FPR. Get both and then adjust your A/F mixture. The off Boost on Boost AF difference sounds normal to me. Most turbo cars do that.
11-28-05, 07:08 AM
#28
Yes, I checked out that link a few years ago. It is not necessarily the "how-to" that interested me. It was the fact that the TPS is on a 0-5v switch, which if you read the SAFC/SAFC2 book you will know anyway. 0V closed or idle, and 5V or close to it at WOT. The maps are switched via the MAP sensor signal instead of the TPS.. Therefore the SAFC/SAFC2 becomes Load sensing as opposed to Throttle sensing. As boost increases, Voltage output from the Map sensor increaes, thus switching the fuel mapping from Lo to Hi. Much more efficient and smoother transition especially with upgraded fuel systems...pumps, injectors..etc.
I also agree with the need for an upgraded adjustable fuel pressure regulator. You need to have the pressure at the rail in a boosted application in order for the SAFC to distribute. Typically on low boost and stock injectors I run at least 10psi more rail pressure than factory specs. After all, the car is not factory spec anymore.
It shouldnt be a wait and see type of attitude. If you have any type of forced induction system, fuel should be the first thing out of the way.
BTW, boost mapping works very well. I have 3 cars running this system since I started experimenting with it over a year ago.. 99 Civic Si supercharged.. currently making 210whp and getting 31 mpg, 00 prelude turbo, 213whp at 5 psi and super smooth driving and good fuel economy.. if he can stay out of WOT..LOL.. And a 91 240sx turbo, 260whp at 8 psi on a very slight and very rich tune. Going back to the dyno shortly and expecting 270whp. The A/F curve is dead flat at whatever I choose to make it.. 11.5-11.8: across the board at WOT for pump gas safety and reliability. The 240sx is a member of my drift team so believe me it gets a work out.
I'll be boost mapping my SAFC2 when I install the rest of the Aristo motor and even the ECU in my car in a few weeks, just for the smoothness of switching SAFC maps on Load.
Good luck Morris.. sounds like you are almost there..
I also agree with the need for an upgraded adjustable fuel pressure regulator. You need to have the pressure at the rail in a boosted application in order for the SAFC to distribute. Typically on low boost and stock injectors I run at least 10psi more rail pressure than factory specs. After all, the car is not factory spec anymore.
It shouldnt be a wait and see type of attitude. If you have any type of forced induction system, fuel should be the first thing out of the way. BTW, boost mapping works very well. I have 3 cars running this system since I started experimenting with it over a year ago.. 99 Civic Si supercharged.. currently making 210whp and getting 31 mpg, 00 prelude turbo, 213whp at 5 psi and super smooth driving and good fuel economy.. if he can stay out of WOT..LOL.. And a 91 240sx turbo, 260whp at 8 psi on a very slight and very rich tune. Going back to the dyno shortly and expecting 270whp. The A/F curve is dead flat at whatever I choose to make it.. 11.5-11.8: across the board at WOT for pump gas safety and reliability. The 240sx is a member of my drift team so believe me it gets a work out.
I'll be boost mapping my SAFC2 when I install the rest of the Aristo motor and even the ECU in my car in a few weeks, just for the smoothness of switching SAFC maps on Load.
Good luck Morris.. sounds like you are almost there..
11-28-05, 03:57 PM
#29
Originally Posted by Epik
Yes, I checked out that link a few years ago. It is not necessarily the "how-to" that interested me. It was the fact that the TPS is on a 0-5v switch, which if you read the SAFC/SAFC2 book you will know anyway. 0V closed or idle, and 5V or close to it at WOT. The maps are switched via the MAP sensor signal instead of the TPS.. Therefore the SAFC/SAFC2 becomes Load sensing as opposed to Throttle sensing. As boost increases, Voltage output from the Map sensor increaes, thus switching the fuel mapping from Lo to Hi. Much more efficient and smoother transition especially with upgraded fuel systems...pumps, injectors..etc.
I also agree with the need for an upgraded adjustable fuel pressure regulator. You need to have the pressure at the rail in a boosted application in order for the SAFC to distribute. Typically on low boost and stock injectors I run at least 10psi more rail pressure than factory specs. After all, the car is not factory spec anymore. It shouldnt be a wait and see type of attitude. If you have any type of forced induction system, fuel should be the first thing out of the way.
BTW, boost mapping works very well. I have 3 cars running this system since I started experimenting with it over a year ago.. 99 Civic Si supercharged.. currently making 210whp and getting 31 mpg, 00 prelude turbo, 213whp at 5 psi and super smooth driving and good fuel economy.. if he can stay out of WOT..LOL.. And a 91 240sx turbo, 260whp at 8 psi on a very slight and very rich tune. Going back to the dyno shortly and expecting 270whp. The A/F curve is dead flat at whatever I choose to make it.. 11.5-11.8: across the board at WOT for pump gas safety and reliability. The 240sx is a member of my drift team so believe me it gets a work out.
I'll be boost mapping my SAFC2 when I install the rest of the Aristo motor and even the ECU in my car in a few weeks, just for the smoothness of switching SAFC maps on Load.
Good luck Morris.. sounds like you are almost there..
I also agree with the need for an upgraded adjustable fuel pressure regulator. You need to have the pressure at the rail in a boosted application in order for the SAFC to distribute. Typically on low boost and stock injectors I run at least 10psi more rail pressure than factory specs. After all, the car is not factory spec anymore.
It shouldnt be a wait and see type of attitude. If you have any type of forced induction system, fuel should be the first thing out of the way. BTW, boost mapping works very well. I have 3 cars running this system since I started experimenting with it over a year ago.. 99 Civic Si supercharged.. currently making 210whp and getting 31 mpg, 00 prelude turbo, 213whp at 5 psi and super smooth driving and good fuel economy.. if he can stay out of WOT..LOL.. And a 91 240sx turbo, 260whp at 8 psi on a very slight and very rich tune. Going back to the dyno shortly and expecting 270whp. The A/F curve is dead flat at whatever I choose to make it.. 11.5-11.8: across the board at WOT for pump gas safety and reliability. The 240sx is a member of my drift team so believe me it gets a work out.
I'll be boost mapping my SAFC2 when I install the rest of the Aristo motor and even the ECU in my car in a few weeks, just for the smoothness of switching SAFC maps on Load.
Good luck Morris.. sounds like you are almost there..