did some tunning last night WOW....

[wiked87gn]

we got one of our coldest nights here in LA last night so i though i do some tunning around 11pm on a long empty street, got my 02's from high 820's to low 790's and dropping on top of third gear to maybe low 780's all i can say is, wow!! what a difference it makes getting your 02's that low the car feels like a total different beast now. I like it .

btw i was running 23 psi, alky,18*timing chip. had to lower my fuel pressure down from 41 line ON to 32 with line ON, i guess those bosch 42.5 green tops dont need that much FP to run great.

 

[1badTTA]

If you had 41psi LINE ON then you had about 50 psi LINE OFF if you have 13 in of vacuum (rough guess, 29in/hg=14.7psi) so your fuel pressure was way off to start with.

Good to hear you got it running better.

 

[wiked87gn]

response.

are you saying i may have an vacumm air leak somewhere and that is why my FP gauge is not reading right?

 

[1badTTA]

Actually what I am saying is that you should pull the line off to read fuel pressure, that way it isn't affected by engine vacuum. Injectors are designed for about 43psi and most chips are burned with that in mind. If you were running 50psi of fuel pressure with the line off (actual fuel pressure at 0 vacuum and 0 boost) then you are putting more fuel into the engine than the chip is calling for (by injector DC) and it would easily explain your high O2 readings. Clear as mud?

 

[wiked87gn]

response

actually line off fuel pressure before i made adjustments was set at 43, after adjudments it now reads 36 and the car seems to like it, before anything above 40 psi line off and the car would run really rich.