View Single Post
  #12  
Old Sun, March 6th, 2011, 11:32 AM
Longshot270's Avatar
Longshot270 Longshot270 is offline
Forum Predator
 
Join Date: Jul 2009
Location: DFW, TX
Posts: 2,688
Longshot270 will become famous soon enough
Default

Quote:
Originally Posted by Jim Allen View Post
I recall Bill telling me to reset every tank but what you say makes sense, Longshot. I'll leave it alone for a while and see how it goes.

A related phenomenon I recently noted is that my mpg readouts were significantly reduced for a while after I disconnected the battery to erase the adaptive memory. I reverted from an AEM CAI back to stock, so I reset my Gryphon to L1 (because Bill had put the special CAI tune in L2) and disconnected the battery to start at square one again. For about 35 miles or so, driven over a road I know well the reading I should be getting, the (instant and average) mpg were down 25 percent or so. At least it started that way. It gradually worked back up to normal levels as I drove. Bear in mind I use that stretch of road as a "track" for testing mpg when I get new test product to play with, so I am very familiar with what I should be getting on the instant reading, even by the sections of road. By the time I was 2/3s of the way, it was more or less back to normal. Engine readapting?
The reason it starts out low then builds back up to the normal range is from accelerating then cruising. When you accelerate you are throwing low numbers into your average. As you cruise you are adding a longer list of normal values. As your normal value count increases the % error from the abnormal values (acceleration values) will diminish. Eventually you'll have enough "good" values that the "bad" values will not be significant. It would only take 21 good readings to make one bad reading disappear from the average. That is why you can make that average shoot up by flooring it for a second or two then letting off and rolling. It only takes a few seconds to go from 30 to 70 but the truck is heavy enough to roll for a while. If you roll long enough, the low readings get displaced by the high ones.

I'll get a datalog later on today to demonstrate this. It'll give me another reason to drive to Lowes for some stuff.
__________________
Reply With Quote