I raised the base pressure from 43# to 45# to add more fueling. How else do you add more fuel when your lean other than the FPR or the chips tuning capabilities? I have never seen my O2 any higher than 710 during a freeway run.
Thanks
~JM~
I Think I'm Running Lean...
- Thread starter ~JM~
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I raised the base pressure from 43# to 45# to add more fueling. How else do you add more fuel when your lean other than the FPR or the chips tuning capabilities? I have never seen my O2 any higher than 710 during a freeway run.
Thanks
~JM~
I didn't write down the rest of the readings. Should I warm up the car in park until the fan comes on & then record my readings? I'm not able to drive it right now due to the weather.
Thank you
~JM~
Do you have access to a different gauge for fuel pressure? Just to double check. I would add fuel in the chip rather than more pressure at the line. Have you replaced the O2 sensor lately? Are you getting any knock at WOT? I am not sure if its possible at this level, but could you be maxing your injectors out?
Nix
Nix
Only have the one fuel pressure test gauge. It's fairly new & only been used on this car. The only way that I had to verify whether or not it reads correctly was when I had my Bosch 237 FPR installed. This non adjustable FPR provides a base pressure of 43# which is what the gauge read also.
I have not replaced the O2 sensor yet & have been thinking that it may need it.
Last full throttle run was the one at the beginning of this post. I had 7 degrees KR & the O2's were in the mid to high 600 range. My O2 readings are all over the place though & it rarely settles on a number for even a second or two. My directions from my TT chip says it should settle in the high 700 range to bottom 800 while sitting at idle. Like I've said earlier, the highest I've seen has been 710.
I have also thought about my 30# injectors not being enough. All I've done to this car so far is concentrate on improving its breathing & removing restrictions to flow. I'm not real excited about buying a new set of 60# injectors & a new chip if its not required, but if it is actually time then that's the next step.
How much base pressure are most running to provide enough fueling for their combo? I know that's a broad question.
Thank you
~JM~
I have not replaced the O2 sensor yet & have been thinking that it may need it.
Last full throttle run was the one at the beginning of this post. I had 7 degrees KR & the O2's were in the mid to high 600 range. My O2 readings are all over the place though & it rarely settles on a number for even a second or two. My directions from my TT chip says it should settle in the high 700 range to bottom 800 while sitting at idle. Like I've said earlier, the highest I've seen has been 710.
I have also thought about my 30# injectors not being enough. All I've done to this car so far is concentrate on improving its breathing & removing restrictions to flow. I'm not real excited about buying a new set of 60# injectors & a new chip if its not required, but if it is actually time then that's the next step.
How much base pressure are most running to provide enough fueling for their combo? I know that's a broad question.
Thank you
~JM~
87Turbolimited
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Check thid out i got it from the vortect turbo!!!
My experience, with my particular cars/combinations, is that at wide open throttle, this is often around 780 mv when running on straight gasoline and somewhat lower...around 740-760 mv when spraying alky. These are wide open throttle numbers at speed in third gear. Now, go look at the factory O2 graph again and understand the futility of guessing a true A/F. Those who have installed wideband O2s that do provide an accurate A/F know how futile this actually is. Given that the output of the factory O2 is affected by heat and pressure, it is easy to see that 800 mv at part throttle may be several air fuel ratios different than 800 mv at wide open throttle.
At idle, with a closed loop chip, the 02s bounce around between 000 and 800 mv. With an open loop chip, they will be fairly stable around 750-800 mv.
Jack-pot! A new O2 sensor looks to have straightened out my readings.
Thank you
~JM~
Jack-pot! A new O2 sensor looks to have straightened out my readings.
Thank you
~JM~
You said you had 7 degrees ignition retard. Changing an o2 sensor won't fix that.
Finally had a chance to drive the car again today. I had installed an adj waste gate actuater & matched the length of the original the best I could. It has me making more than 20#'s of boost. The car runs great at 15#'s with the 92 octane fuel that is in it & no knock. My theory that my new FMIC would lower the amount of boost due to less restriction was wrong, it appears to have increased the level of boost over the SLIC.
Does anyone know if you can count the number of threads on the wastegate actuater & know how many lbs. of boost has been changed, or is it strictly trial & error?
Thank you
~JM~
Does anyone know if you can count the number of threads on the wastegate actuater & know how many lbs. of boost has been changed, or is it strictly trial & error?
Thank you
~JM~
jm,stop dont put your foot to the floor!please dont take this the wrong way but playing with boost and fp is just the quickest way to hurt things,you will need octane to run the car at 20 psi without knock,that can but done with alky or race gas.knock is not going away with a new 02 sensor as stated above.lengthening the rod will lower the boost, on 92 octane pump= 13/15 lbs.
