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Wildkarde · 03-31-2018, 01:19 AM

The only GM computers that don't default to low octane tables when the MAF is failed are the ones used in LS2 and LS7 applications. There's nothing wrong with running speed density if you need to because you are flowing too much airflow for your MAF sensor to handle or have a really monster cam, but just unplugging the MAF sensor is a terrible way to do it. Honestly going straight SD should be a last resort, the car will run better in most applications with the MAF. Especially E38/E67 Gen 4 stuff that rely even less on SD normally.

Not only are you running the low octane spark table, most of the LS engines including all of the gen 4 stuff has the IAT sensor included with the MAF sensor. The IAT sensor is a big part of airflow calcs when running speed density.

While your engine may run smoothly with the MAF unplugged dave, that doesn't mean it's running at anywhere near its peak. GM's VE tables, especially the virtual VE tables used in the E38/E67 computers are known to be fairly rich. This is a safety issue since things like clogged airfilters heavily effect the accuracy of SD, and while the narrowband O2's can correct this at idle/part throttle they are no help during PE. And rich is at least safe, or least until you get so rich you start washing cylinders down.

03-31-2018, 01:19 AM	#1
Wildkarde Registered User Join Date: Mar 2018 Location: Ardmore Posts: 100	Re: 6.0 runs and quits The only GM computers that don't default to low octane tables when the MAF is failed are the ones used in LS2 and LS7 applications. There's nothing wrong with running speed density if you need to because you are flowing too much airflow for your MAF sensor to handle or have a really monster cam, but just unplugging the MAF sensor is a terrible way to do it. Honestly going straight SD should be a last resort, the car will run better in most applications with the MAF. Especially E38/E67 Gen 4 stuff that rely even less on SD normally. Not only are you running the low octane spark table, most of the LS engines including all of the gen 4 stuff has the IAT sensor included with the MAF sensor. The IAT sensor is a big part of airflow calcs when running speed density. While your engine may run smoothly with the MAF unplugged dave, that doesn't mean it's running at anywhere near its peak. GM's VE tables, especially the virtual VE tables used in the E38/E67 computers are known to be fairly rich. This is a safety issue since things like clogged airfilters heavily effect the accuracy of SD, and while the narrowband O2's can correct this at idle/part throttle they are no help during PE. And rich is at least safe, or least until you get so rich you start washing cylinders down.