Engine/Transmission (1998.5 - 2002) Smarty better at 3/4 throttle ??

[isb360]

OK, first I thought it was my imagination, but I've done several "experiments" and this seems to be what I am experiencing:



Accelerate 70-100mph on flat grade 5th gear @ WOT



Accelerate again 70-100mph on same grade 5th gearwith 3/4 throttle.



Guess what? It really feels quicker at 3/4 throttle than full throttle. In each case Smarty is on #9 (of course... !) and PM3 box is off. My butt isn't calibrated, but I can feel the difference...



It is harder to detect this phenomenon in lower gears because the truck pulls through the gears so well, but can also tell this a bit in 4th. I don't know if it might be an APPS calibration issue or a Smarty issue, or am I just using all the fuel the truck needs to go at 3/4 throttle and anything over that is excess? Smokes a bit at low rpm's until on boost, but 70-100mph has me on boost to start, so not an issue



Anyone else experience this? Marco/Bob?



Thanks

Tim

 

[Fishin Guide]

OK, first I thought it was my imagination, but I've done several "experiments" and this seems to be what I am experiencing:



Accelerate 70-100mph on flat grade 5th gear @ WOT



Accelerate again 70-100mph on same grade 5th gearwith 3/4 throttle.



Guess what? It really feels quicker at 3/4 throttle than full throttle. In each case Smarty is on #9 (of course... !) and PM3 box is off. My butt isn't calibrated, but I can feel the difference...



It is harder to detect this phenomenon in lower gears because the truck pulls through the gears so well, but can also tell this a bit in 4th. I don't know if it might be an APPS calibration issue or a Smarty issue, or am I just using all the fuel the truck needs to go at 3/4 throttle and anything over that is excess? Smokes a bit at low rpm's until on boost, but 70-100mph has me on boost to start, so not an issue



Anyone else experience this? Marco/Bob?



Thanks

Tim

I had experienced this as well. My theory was that the ECM was adding more timing at a lesser APPS voltage level. I have nothing factual to base it on.



With the PM3 on, that seems to flip flop. I am guessing the TST and it's adding fueling also have an effect on timing and just power through that 3/4 throttle area.



Dave

 

[isb360]

Thanks for the info. I will put my TST on #3 or something and give it a whirl. Speaking of whirls, my turbo is whirling to pretty high EGT's just with Smarty and Mach II's, and the Smarty with timing seems to keep them under control better than the TST... doesn't rise as fast



If it is a Smarty-induced condition, it would seem like the extra fuel provided by TST would "mask" it?



Tim

 

[Fishin Guide]

I don't know what causes it, that's for certain! The TST may be very well masking it. I can tell you this, while it feels better on the street, 3/4 throttle does make less HP than WOT on the dyno. I actually tested it.



Now, time to RPM ect was not measured, so it may ion fact get to the same rpm at a faster rate at 3/4 throttle. I am unsure.



Dave

 

[Graphic man]

did you try an APPS reset?

 

[Fishin Guide]

did you try an APPS reset?

APPS reset, APPS recalibration, changing ecm, pcm also had no effect. This includes changing IAT, MAP and cam position sensor.



Mine is more driveable with the updated program, but it will still exhibit the symptoms. Oh well, small price to pay for what we get out of it.



My hope is that Marco is going to work on refining the 2nd Smarty after the 3rd gen stuff is out there and working.



Dave

 

[isb360]

My Smarty is serial # 250, or thereabouts, so it's an "early" one, I think, definitely without the surge-fix program. Being that mine is a 98. 5 with a stick, I wasn't experiencing any or much of the surge seen by folks in the '02 autos. I will have to get the update off Marco's site soon, however, just to make sure I am up to date.



Last night I turned PM3 on to #3. What a pleasant difference. Definitely a bit more smoke, but seems to mask the condition as you indicated yesterday. Of course EGT's are shooting up faster, but nothing my right foot cannot control.



Thanks for the tips



Tim

 

[DirtyDodge]

My surge issue is now gone! Oo. I have the Smarty #7 loaded. It has full pedal range, cruise is working perfectly again. I could not be happier with the results of the updated surge software.

 

[Devan Manis]

this surge software you speak of, is that for cruise control, so that its not always surging while just have the cruise control on.

 

[Tcolesanti]

isb360, just a quick question(s), does it seem like the motor just has more RPM gain (faster) at 3/4 throttle versus wide open throttle? And when you turned on your TST, did this condition go away? Have you checked the volts at your APPS? If so what were they wide open/closed throttle? Thanks

-Tom

 

[OWeigel]

I think Marco has shortened the throttle a bit. The program #4-9 with the Catcher Sw's are the same power(ie #4,6,8 and #5,7,9) with different agressive settings. And a part of it may be the throttlelength.

WOT at #9 should be like 1/2-3/4 of the stock throttleresponse, and you really feel when you overthrottle. Let it up a bit and you feel the power come back(almost like an old carburated overfueled gasser).



This is what i remember from the old Catchertread and I´m not going to try finding it again(read it twice and thats enough

Maybe Marco chime in and correct me if I´m wrong.