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100041, leaning out on 3rd gear while boosting
Posted by pete@6psi, May-07-07 08:56 AM

can someone tell me what's wrong...i'm using a cartech fmu...with fuel pressure at about 30 psi...now when i boost a 3rd gear it leans out...1st, and 2nd gears are fine...its just 3rd gear that i'm leaning out...any help would be appreciated

100044, RE: leaning out on 3rd gear while boosting
Posted by cs82685, May-07-07 10:08 AM

Originally posted by pete@6psi
can someone tell me what's wrong...i'm using a cartech fmu...with fuel pressure at about 30 psi...now when i boost a 3rd gear it leans out...1st, and 2nd gears are fine...its just 3rd gear that i'm leaning out...any help would be appreciated

fuel pressure at 30psi when?
what size injectors?

need more info to help

100047, RE: leaning out on 3rd gear while boosting
Posted by pete@6psi, May-07-07 10:22 AM

i have HR 270cc injectors...30 psi at idle...using a wideband to tune...while boosting on 3rd gear the wideband reads 13.xx...i know the safe reading is below 12.xx...

100048, RE: leaning out on 3rd gear while boosting
Posted by VelocitaPaola, May-07-07 10:26 AM

You do realize that the stoichiometric AFR for gasoline is 14.7, right?

-http://www.symtechlabs.com/-

100049, RE: leaning out on 3rd gear while boosting
Posted by pete@6psi, May-07-07 10:31 AM

Originally posted by VelocitaPaola
You do realize that the stoichiometric AFR for gasoline is 14.7, right? -http://www.symtechlabs.com/-

What? I don't know what you're talking about.

100050, RE: leaning out on 3rd gear while boosting
Posted by VelocitaPaola, May-07-07 10:35 AM

Never mind, I don't know what my point was...

Tuning with just a Cartech seems arduous. Have you considered upgrading to something else?

And what psi of boost are you beginning to lean out at? How about RPMs? What gear you're in doesn't tell us much.

-http://www.symtechlabs.com/-

100051, RE: leaning out on 3rd gear while boosting
Posted by pete@6psi, May-07-07 10:40 AM

Originally posted by VelocitaPaola
Never mind, I don't know what my point was... Tuning with just a Cartech seems arduous. Have you considered upgrading to something else? And what psi of boost are you beginning to lean out at? How about RPMs? What gear you're in doesn't tell us much. -http://www.symtechlabs.com/-

yeah..i also have vortech sfmu..but i'm not sure how to work it...i'm boosting at about 6psi...it starts to lean out at about 4500-5000 rpm...

100052, RE: leaning out on 3rd gear while boosting
Posted by VelocitaPaola, May-07-07 10:44 AM

Oh ok; you're in pretty good shape if you have an S-FMU and you're only boosting 6spi.

Do you know which spring is in the S-FMU?

-http://www.symtechlabs.com/-

100054, RE: leaning out on 3rd gear while boosting
Posted by totaleclipse_05, May-07-07 10:46 AM

Does it stay lean through your whole 3rd gear pull or does it richen up after a little while. On my car I am using a 12:1 Vortech FMU and when I hit 3rd gear, it leans out for a few seconds on my narrow-band gauge, but then richens up. What type of fuel pressures are you seeing at 6 psi?

100058, RE: leaning out on 3rd gear while boosting
Posted by pete@6psi, May-07-07 11:02 AM

Originally posted by totaleclipse_05
Does it stay lean through your whole 3rd gear pull or does it richen up after a little while. On my car I am using a 12:1 Vortech FMU and when I hit 3rd gear, it leans out for a few seconds on my narrow-band gauge, but then richens up. What type of fuel pressures are you seeing at 6 psi?

i'm using a cartech fmu...i also have a vortech sfmu but like i mentioned i don't know that works...so i put that aside and not using it until i get some help on how it works...maybe you can tell me...how did you hook the vortech sfmu...could you send me some pix (if you have any of your sfmu setup)...and about the problem that i have...when i hit 3rd gear my wideband reads a steady 13.xx...on 2nd gear it reads 11.xx...