In a previous post (actually kinda hijacked someone else's), we were talking about gas mileage and the 5.4L. I did a short run with my 5.4L with the SuperChips programmed to "Tow-Perf" mode, and got 11.5 mpg. Even though it was just a fairly short tow, it was still a promising figure. Well, I did not retune the chip and did a run from Houston to San Antonio in the Tow-Perf mode (nothing being towed) with the SuperChips preselected options, and here are the results:

I love the way it drives. The transmission really shifts smooth. More power out of the gate, though not anything to write home to Momma about. Better power in the mid range (from about 30 - 50 mph). Gas mileage...sucks! Went down to about 13.1. I wasn't necessarily heavy on the pedal, maybe a little aggressive, but not bad.

Coming back from San Antonio to Houston, I reprogrammed to straight "Performance" mode, with the SuperChips preselected options. Still has the better "git up and go" off the line, but still nothing to write home about. Still has the better mid-range performance. Shifting was noticeably "heavier". Don't really know how to describe it in a few words, but you could sure feel the shifting as compared to the Tow-Perf. Gas mileage...Wow. 16.1 mpg!

I was getting on average, around 14.5 - 15.5 with the SuperChips in 87 Octane mode. Not sure what that mode is supposed to do for you!

My impressions? Well, I still say it's a bit too early to close the door on this. I'll keep it in Performance Mode a bit and run it through a couple of tanks of gas and see how she does. The increase in actual horsepower and/or torque are there, but as I said, it's not gonna be anything to write home about, like the reputed gains from a diesel. But I feel pretty good initially.

A couple of other things. I sure wish I knew what the custom options on that SuperChips programmer actually did. In particular, the shift points and shift pressure. The other stuff (tire height, gear ratio, etc.) is self explanatory, but the settings for the shift point and shift pressure are "min----|-----max" (or something like that). Does anyone know what changing these settings actually does?

Also, the gas mileage calculations were done the old fashioned way. Math (YUCK!). I have no onboard computer to lead me astray.

 

Was that the MaxMicro tuner? I missed the previous posts.

 

So far it looks very promising. Thanks for sharing your results so far, Ed.

 

I too would like to know something about shift points. I know I have plenty of power in a 5.4 to tow an empty 12' enclosed trailer but at 70 mph. it kept downshifting everytime I started up a minimal incline on the interstate.

 

The shift point is the RPM or MPH that the computer shifts into the next higher gear. I think superchips uses RPM, in 1-2 shift you can only increase the stock by 200 or so rpms. At 300 rpms over stock on WOT, I hit the rev limiter and had to come out of the throttle to shift into second. My set up is 1-2 100 over stock, 2-3 200 over stock and 3-4 300 over stock.

Shift pressure is a sliding scale on the tuner, superchips prefered setting is usually right in the middle. Move the marker to the left to increase shift firmness/pressure and right to decrease shift firmness/pressure. As I understand it, it makes more pressure in the vavle body and makes the clutches engage more rapidly and with more clamping force. While it's a lot of fun, I have heard that it can strain the pump. So I opted for a valve body and stock shift pressures and got better results.

 

That's a gearing/load issue. Even with increased line pressure the computer will command a downshift.

 

Yes, the MaxMicro, model 1715.

Great stuff on the shifting. I think I have a better handle on it. I'll have to play with it some. Not a whole lot though. The Superchips settings do pretty good, though I'd like to get that smooth shifting of the Tow-Perf settings on the Performance tune.