Open loop operation???
Thread Starter
TECH Junkie
Joined: Nov 2001
Posts: 3,987
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From: Melbourne, FL
Open loop operation??? I'm thinking of trying some stuff out with my new engine when it gets here and I get my car going again...
What, if any, downsides would there be to removing my O2 sensors completely, and setting up everything to run in open loop constantly. Driveability and fuel economy are completely out the window, so I don't consider that a downside. I'm talking strictly performance wise. I may be wrong here, but I feel that things (AF ratio, spark advance) could be kept much more constant this way. The car would be tuned using fuel pressure adjustments and LS1-edit.
Seems to me that this would be the way to go, for someone who has zero concern about driveability/part throttle manners... Plus, splashing a little leaded race gas into the tank would cause no problems.
What, if any, downsides would there be to removing my O2 sensors completely, and setting up everything to run in open loop constantly. Driveability and fuel economy are completely out the window, so I don't consider that a downside. I'm talking strictly performance wise. I may be wrong here, but I feel that things (AF ratio, spark advance) could be kept much more constant this way. The car would be tuned using fuel pressure adjustments and LS1-edit.
Seems to me that this would be the way to go, for someone who has zero concern about driveability/part throttle manners... Plus, splashing a little leaded race gas into the tank would cause no problems.
TECH Regular
Joined: Nov 2001
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Re: Open loop operation??? I think that our cars over here always run in open loop operation because my car does not have O2 sensors in the exhaust. Furthermore, I did not get a check engine light when I gutted the cats (no O2 sims either).
However, they don't do emission testing here <img src="gr_images/icons/wink.gif" border="0">
However, they don't do emission testing here <img src="gr_images/icons/wink.gif" border="0">
TECH Addict
Joined: Nov 2001
Posts: 2,207
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From: College Station, Tx
Re: Open loop operation??? I run my LT1 in open loop mode exclusively. With big cams it's especially helpfull since they may not always like 14.7:1 <img src="gr_stretch.gif" border="0">
It's not like a carb'd setup - you still have atmospheric, etc. corrections (not to mention it's MAF based so quite a bit of the guesswork is taken out) - you just have to dial in your tables a bit better.
Chris
It's not like a carb'd setup - you still have atmospheric, etc. corrections (not to mention it's MAF based so quite a bit of the guesswork is taken out) - you just have to dial in your tables a bit better.
Chris
Thread Starter
TECH Junkie
Joined: Nov 2001
Posts: 3,987
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From: Melbourne, FL
Re: Open loop operation??? OK, so it's not a "stupid" idea, then... I think it may be a little easier to dial in my new motor this way, plus not have to worry about the delicate O2 sensors if some leaded gas happens to find it's way into the tank.
I'll give it a shot <img src="gr_grin.gif" border="0">
I'll give it a shot <img src="gr_grin.gif" border="0">
Teching In
Joined: Jan 2002
Posts: 22
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Re: Open loop operation??? If I'm not mistaken, GCC (Gulf) Spec cars use a MAP system instead of a MAF+ O2 sensors... Can somebody elaborate on this a bit more? I'm also assuming the Gulf cars have a fixed fuel/air maps depending on MAP reading... Again, more information on the matter would be highly appreciated, thanks
