Opinions needed, A/F vs boost
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From: Albuquerque, NM
Opinions needed, A/F vs boost I need some advice on my Dodge STS setup. If not familiar with it, STS puts an extra injector in the intake tubing just before the TB. It then uses a Hobbs style pressure switch to activate the injector, which then pulses off of two stock injector signals.
Ok, I have a TiAL wastegate and installed a yellow 0.25bar/3.5psi spring for a "wife and highway" mode with a dual stage boost controller switch inside the cab ( don't ask about the computer programming, none exists ).
Finally the question. Do I need to maintain < 13:1 A/F or stoiciometric - 14.7 at 3psi of boost? I am looking to save a few drops of fuel but not at the expense of my motor.
Thanks for any help!
Ok, I have a TiAL wastegate and installed a yellow 0.25bar/3.5psi spring for a "wife and highway" mode with a dual stage boost controller switch inside the cab ( don't ask about the computer programming, none exists ).
Finally the question. Do I need to maintain < 13:1 A/F or stoiciometric - 14.7 at 3psi of boost? I am looking to save a few drops of fuel but not at the expense of my motor.
Thanks for any help!
3 psi is not worth the trouble when a decent but not huge cam and a good set of heads would do the job.i made your hp number with a GT2-3 babe cam only so...your sig says 5 psi so why do you want to drop to 3 psi?just stay out of boost and youll be fine as you are.
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From: Albuquerque, NM
Originally Posted by ddnspider
3 psi is not worth the trouble when a decent but not huge cam and a good set of heads would do the job.i made your hp number with a GT2-3 babe cam only so...your sig says 5 psi so why do you want to drop to 3 psi?just stay out of boost and youll be fine as you are.
Any thoughts on 3psi and A/F?
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From: Albuquerque, NM
Originally Posted by parish8
if your at WOT and 3psi you will want to be richer than 14.7. even NA you want to be around 13-1 at WOT. i would say keep it at least in the 13-1 or richer range.
I am going to wire up a switch on the throttle cable near the TPS ( electronic controller ) that cuts off the extra injector if the TB is not open above 75% or so. This way I can have the extra fuel under load but not cruising around the neighborhood. The std T60 will provide 3psi of boost around 2000rpm or less and my fuel mileage is suffering due to the limits of the pressure activation switch.
BTW if this sounds like a lot of backyard engineering it is. There are some better ( and more expensive ) options out there but I am trying to see what the poorer man can do with this kit instead of investing additional money above the basic price. Can't wait til someone breaks the DC computer codes and intro's a HemiEdit or similar product.....
