Hi Mike,

This is Tanguy form Houston, I spoke to you on the phone yesterday (10/2) regarding my new '03 F150 Screw FX4 and towing my '97 Procharged Mustang. My question is regarding the Micro Tuner, does it optimize shift points for the tranmission?

 

Hi Tanguy,

Sure, I remember talking to you yesterday - nice to see you drop by here, too!

Yes, the 1715 Micro Tuner does already optimize the shift points in it's default tuning - and it also allows you to make manual changes to each shift point individually, if there is a problem that actually needs to be fixed due to certain mods. You can adjust the 1-2, 2-3 & the 3-4 shift points individually, as well as their shift pressures individually for each gear change.

However, we recommend just taking all the defaults, and not doing *manual* changes to shift points for at least a month or so after installation, so you'll know just what the new shift points are - they're already optimized, so only very rarely does anyone ever actually need to adjust them manually, as the unit allows. Just take the defaults & drive it like that for a month before making any manual changes to shift points, is our advice.

Have fun & talk to you soon!

 

Mike this got me thinking about something. I currently have the 3.08 gears in my 150 but plan on changing them in the near future to 3.73 or 4.10. I know that the stock settings on the 1715 adjust the shift points to optimum in the performance settings. However, my question is this. When I change the gears and then make the adjustment for the speedo with the 1715 to reflect my new gears will this change my shift points to match up to the new gears? In other words, does the PCM look at the RPM only for shift points or does it look at both RPM and speed??
Thanks in advance.

 

Hi cg,

The PCM "looks" at numerous data streams in determining part-throttle shift characteristics & shift points, including vehicle speed, throttle opening & load (ve) - in some cases rpms as well - but it's mostly looking at vehicle speed as opposed to engine rpms when we're talking about the part-throttle shift points, I.E., shift points @ less than about 82% throttle opening.

On full-throttle (actually, in most codes from about 82% throttle on up to full-throttle), that is no longer a variable based on vehicle speed, throttle position and load, but instead becomes a set commanded value so that signal will be sent to the transmission at the same time, every time - so the **full-throttle** shift points are not variable like the part-throttle shift points are. This can take a little work when there are mechanical mods to the tranny (a race-built tranny like Neal's, or a shift kit, or a Factory Tech valve body, all of which we carry), due to the affect on clutch fill times - mechanical mods generally quicken transmission fluid volume flow rates, thus reducing clutch fill times, thus we have to reduce how far ahead of time (rpm-wise) we have to send that signal to the tranny to execute the upshift.

We have to know the rate of acceleration at full-throttle in each individual gear (or at least a good approximation), I.E., an acceleration rate of 1000 rpm per second in 1st gear @ WOT means we have to send the signal about 1000 rpm before we want the tranny to shift, due to the approximately 1.0 second (a full second) for clutch fill time in these 4R70W truck trannys.

The shift points are adjustable with the Micro Tuner, however, as just about everyone has seen me say many times, we advise using the Micro Tuner's defaults for the first month or so before trying to make manual changes to the shift points (as in most cases manual changes will only slow the vehicle's rate of acceleration down at heavy throttle). This is so everyone knows how their vehicle feels & performs with the default Superchips shift points - otherwise they have no comparative basis for making such changes.

OK, now with all of that aside, to get to your actual question.............

When you change gears, you use the Micro Tuner to recalibrate the speedometer, and that process also automatically corrects the shift points in 1999 & newer trucks as a general rule, just like changing the speedo gear in a 1997 or 1998 F-150 to recalibrate the speedo in those model years also fixes the shift points. So just correcting the speedometer with the Micro Tuner will generally clear up shift point deficits caused by either gear ratio or tire size changes.

 

Cool thanks Mike for the in depth on that. I know more now that the 1715 will do exactly what I need it to then so thanks for putting that thought to bed.

 

You're very welcome Chris, & by the way - that's a *very* pretty truck you have there!

 

Thanks! It will be much prettier when get everything done. Still gotta lower it, get some ground effects and bumper cover, clear corners, silverstars, chip, etc. but it is getting there.

 

Yeah, it's always something, isn't it? We're never satisfied with our trucks!

I have to confess that we do almost nothing to our trucks cosmetically, we're so focused on performance & speed costs so much $$$ - our personal vehicles tend to be quick, but nothing exceptional to look at.

Keep up the good work, that's a beautiful truck!