FAST classic tuning help

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Jul 30, 2010 | 01:56 PM

James J

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Joined: Jun 2003

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From: Salt Lake Utah

FAST classic tuning help

I have a FAST classic sequential ECU. I've spent a couple of days attempting to modify the VE table due to exhaust and other engine mods - without much success so far. The wide band O2 sensor is functional but doesn't react consistantly until I rev the engine without any load. In general, the motor is 379" sbc high compression, a big cam, 1 7/8 - 2" step headers into a NASCAR style cross-over and boom tube, 57 pound racetronix injectors. I've logged to my laptop in open loop and see the injector duty cycle drop down intermittantly. I would then increase the VE value at that point in the table, re-log and get the same lean condition in the same place. I'm unsure if the O2 sensor is the problem or what's going on.

Any experts out there willing to opine as to what's happening?

I've quizzed a tech at F.A.S.T. but have not heard back from them - -

Thanks in advance for thinking about it!

Jul 30, 2010 | 04:07 PM

bjankuski

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Joined: Sep 2001

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From: Glenbeulah Wi

Check to see when your closed loop operation is set to function. The closed loop operation may not happen until the engine hits 1800 RPM and it may turn off at 1600 RPM. I am only guessing at your issue but maybe you are having an issue related to the closed loop operation. Another item to check is what are the closed loop values for the commanded MAP values and RPM, it is possible that you are commanding a very lean AFR and the engine is giving you what you are asking for. This table will be located under the closed loop flyout.

Jul 31, 2010 | 03:58 PM