Tuning help...

[westonboege]

Alright.. i just bought an innovative lm1 wideband o2 sensor. I want to get a solid street tune down before i go to the dyno. Just looking for what you more experienced guys recommend me starting at as far as fuel pressure.. what you set for the high and low throttle settings on the safcII.. i was under the impression that the stock ecu will handle everything under WOT. If so i dont even need to mess with the low throttle air corrections correct?

Well here are all my mods..
87 turbo... stock rebuild about 15k miles ago
LIPP/BOSS TO4E 54
Aeromotive AFPR
Precision turbo 550 cc injectors
Lex afm
Apexi SAFCII
Greddy Profec B spec II
Lightweight alum. driveshaft
Spearco 1080cfm intercooler with 2.5" hardpipes
Apexi air Filter
Full 3" turboback exhaust to apexi can(no cats)
Egr Blocked off... Jtube block off
Walbro TT fuel pump
HKS BOV to atmosphere

Car is set to about 10psi right now... probably up the boost to around 12-15 not sure yet what i wanna run... anyone know what psi i would be running to achieve about 400 hp?

The wideband im getting has datalogging as well...

 

[dbsupra90]

its always better to start out on the rich side.
yes the ecu will take care of anything below 75% throttle.
for the low map/ high map crossover point ive found that setting it for 74% on the low and 75% for the high works really well. youd think that setting the low throttle point at say 15% would work the best, but since the ecu will counteract any settings that low i found setting it higher has a much better response.
about fuel pressure, its hard to say. i would start with 36psi (vac line not attached). see where you are and adjust from there. as long as the a/f is safe, i stop there. then i use the afc to flatten the curve. then i go back to fuel pressure and start turning that down until the curve is moved to the a/f i want. i usually shoot for 11.8:1 range. it is the best compromise of safety vs power.

good luck!



edit: i forgot you arent far from me. if you wanted to come down to the dyno in new albany i could help you out. i know the owner and could get you a good deal too. just a thought.

 

[westonboege]

how far is new albany? Sounds like a plan... once i get a good tune down i might have to get ahold of you...

I adjusted my fpr today... and when i disconnect the vac line the pressure stays in the same place.... is this normal.. i expected it to move...

 

[Michael90t]

how far is new albany? Sounds like a plan... once i get a good tune down i might have to get ahold of you...

I adjusted my fpr today... and when i disconnect the vac line the pressure stays in the same place.... is this normal.. i expected it to move...

Ummm the FP Should change when you disconnect the vacuum line.... in reality it SHOULD raise a bit as when idleing the car is seeing vacuum.

Michael M

 

[westonboege]

hmm... what vac source do you guys use for aftermarket afpr?

 

[Michael90t]

Stock FPR VSV line....

 

[westonboege]

i think im gonna check my vsv tomorrow .. i think im just gonna get rid of it...

 

[hottscennessey]

I'm with DBSupra90 on this, hes given me great tuning tips in the past which have helped me tuninig my car. This is a good tip he gave me a few months ago.. remember the SAFC isnt linear, +5% at 2k rpms isnt necessarily the same as +5% 5k rpms.

and my contribution is, if you're having problems with fuel cut try upping the fuel pressure and cutting back on the signal.

 

[westonboege]

i shouldnt be boosting near fuel cut yet... probablly gonna tune for like 13-14 psi on the street... or ill eat my tires up in a week.. hehe..

Anyone know what boost dr jonez's mbc will run safely?

 

[dbsupra90]

thanks for the kind words guys! glad i could be of some help.

as far as the mbc, i know dr ran 20psi with it. as a general rule a boost controller will double your wastegate spring.

 

[westonboege]

hmm... i looked at my vsv and i had the fpr hooked up right but a vacuum line fell off the vsv... i disconnected the vsv and connected the two vacuum lines... now the engine is leaning out at idle and almost dying... if i rev it up a little bit a/f goes back to normal...

sounds like i need to check all the other vacuum lines.. also... i screwed my afm screw a few turns in a few days ago... does screwing it in lean or fatten it?

 

[hottscennessey]

screwing it in richens the mixture, backing it out leans it

 

[aljordan]

I would reset the ECU by pulling the EFI fuse in the fuse box under the hood. It's problee been running like that for so long that the ECU has made its long term fuel adjustments.

Clearing teh ECU will clear those adjustments and should bring it back to normal.

 

[westonboege]

Alright... i got the fuel pressure gauge working, and the boost controller working... im still only running 12psi of boost and at high boost i get alot of misfiring... plugs and wires are getting old so i think im gonna replace those next... with a closer gap and maybe colder plugs...

could this be misfiring at idle and making the computer lean out the engine? If the plugs arent firing it will read rich advance timing?

I cleared the ecu also..