I have a quick question for those of you Z owners with good knowledge...

I have 03 Z (66K miles) with stillen SC with 600ccx6 injectors(7th deleted), 255 fuel pump with Osiris ECU (got rid of the ("black box") piggy back. I am about to put comp pulley (stage 4) and taking it in for retune. I just got wideband gauge so I can monitor A/F as well.

What is the leanest a/f ratio for stock internal vq35de?? Is it around 13? or is it too lean? Remember, I want SAFE # for normal daily use.

Thanks!

Romi

 

12ish+ is good like 12.something. I would add a little more fuel at peak torque and lean it out a bit at peak HP.

OSIRIS FTW!

 

I think the pro's keep it in the high 11's for a safe conservative tune. Some may even go into the low 12's.

 

When i had my stage 4 the richest it would run under boost was high 11,s but asking about how lean dosent make sense as when you let off the gas it goes lean anyway.

 

Hes basically asking the leanest he can go safely without his motor going boom.

Your are asking what every single person asks when they go for a tune buddy. Let your tuner take care of that. Some tuners go more for the ragged edge, some go for more safer so they don't blow up a motor. There's no auto best condition for all cars. This is why you dyno tune your car, to find the best tune for you.

 

at wide open throttle u want to be a low 12 on the hit and then level off in the high 11's as the rpm's rise ...at redline should be around 11.7-11.8..

 

^^^That's what I wanted to know. Thanks sir! That was what I thought^^^

Thanks for input everyone. I did and am getting dynotuned by Intec in Kent, WA. I know it is really lean on low rpm/idle but wanted to know when it is full-throttle. I know he tuned it on safer side so, wanted to know what's like on the UNsafe side... I know stock is set at 12 in mid range and high 11s in higher rpm so thinking it can't handle much leaner or it'll go boom I guess.

Let me know if anyone disagrees with this...