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Rocker adjustment....

Reply #121
Jay setting the TPS to .60 allows the ecm to run WOT parameters earlier. It adds to 2.71. Another words the .60 + 2.71 will be 3.31 and command WOT with less throttle opening. lets say you set at 1.0 add that to 2.71 and you get 3.71. Much higher number to trigger WOT. Another words more throttle opening to accomplish WOT parameters.Always set for the lower numbers to bring in WOT parameters sooner. Thanks
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

Rocker adjustment....

Reply #122
Stacks you are pushing on those TPS numbers. It does make a big difference where it is set as i explained. SES light is at or around .5 and 1.31. So beware and always shoot for lower numbers not higher numbers as i explained. >6 is the ticket. Been doing it for many years.
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

Rocker adjustment....

Reply #123
Vinny never use the MIN IDLE screw to set the TPS. That is totally incorrect
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

Rocker adjustment....

Reply #124
I don't know if I'm just not understanding Tom correctly (verbiage) or if he thinks the EEC works differently than it actually does.

The EEC learns the base throttle voltage when the car starts. The TPS sensor is linear as far as I know. The EEC performs all of its TPS calculations from a voltage delta over base voltage.

You could have a range of 1.0-4.5V from closed to fully open, or 0.6-4.1V from closed to fully open. WOT will NOT be reached sooner, unless the TPS sensor doesn't report values linearly from linear movement of the throttle body's butterfly. From the base value, extra voltage from the throttle body opening will increase at the same rate no matter where the voltage starts, and hit WOT at the same spot since this is all relative to base voltage.

Examples with a 5v reference - I think I remember seeing roughly 3.5V between base and fully-open TB:

1.00V base idle
1.88V throttle body 1/4 open
2.75V throttle body halfway open
3.63V thtottle body 3/4 open
3.71V WOT engaged
4.50V throttle body completely open

0.60V base idle
1.48V throttle body 1/4 open
2.35V throttle body halfway open
3.23V thtottle body 3/4 open
3.31V WOT engaged
4.10V throttle body completely open

WOT happens at the same point of the throttle body opening. The voltage means nothing other than being a signal based on delta from base idle.
1988 Thunderbird Sport

Rocker adjustment....

Reply #125
Quote from: TOM Renzo;440430
Jay setting the TPS to .60 allows the ecm to run WOT parameters earlier. It adds to 2.71. Another words the .60 + 2.71 will be 3.31 and command WOT with less throttle opening. lets say you set at 1.0 add that to 2.71 and you get 3.71. Much higher number to trigger WOT. Another words more throttle opening to accomplish WOT parameters.Always set for the lower numbers to bring in WOT parameters sooner. Thanks


Higher voltage yes, but how would it correlate to more throttle opening needed? 

Let's say that the start point; i.e. a closed throttle blade is ZERO POSITION for all intents and purposes. Whether you set the TPS voltage for the zero position to .6, 1.0, or any other value within parameters is moot, no? The voltage required to achieve WOT parameters is the same 2.71+V @ zero position....  Your start/stop point should be the same.  The voltage seen at those will be different based upon voltage at the zero position. 

The theory of setting it to .6v is akin to the same one stating that the TPS must be set to .9999v so long as the zero position voltage PLUS WOT trigger voltage is less than Vref, which is approximately 5 volts. 
If you're telling me you want that number as far from Vref as possible I can see your point.  Otherwise, I'll disagree.

Shoot for the middle ground IMHO.  The ECU takes note of the voltage in the key on engine off position every time because it WILL vary with temperature/humidity/whatever else(radiation from the nearby reactor?  LOL!)

BASE IDLE RESET PROCEDURE
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!

Rocker adjustment....

Reply #126
I set the TPS with the adjuster on top of the throttle body. The only time I use the adjuster screw on the throttle body is when I will set the base idle. Right now, my TPS is set at .95.  I have an NOS Ford TPS in route and it will go on when it gets here. Today on the way to work, the car pulled strong when I started it and took off, then, about 90 seconds later or so, it started that thing it does, a little pop through the throttle body (just one), and running a wee bit rough. SO, I turned the car off, and it restarted it, ran strong for about 90 seconds or so, then back to the same old stuff. No time for anything today, just work. I posted the KOEO codes, balance test and other codes soon.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Rocker adjustment....

Reply #127
Quote from: vinnietbird;440440
I set the TPS with the adjuster on top of the throttle body. The only time I use the adjuster screw on the throttle body is when I will set the base idle. Right now, my TPS is set at .95.  I have an NOS Ford TPS in route and it will go on when it gets here. Today on the way to work, the car pulled strong when I started it and took off, then, about 90 seconds later or so, it started that thing it does, a little pop through the throttle body (just one), and running a wee bit rough. SO, I turned the car off, and it restarted it, ran strong for about 90 seconds or so, then back to the same old stuff. No time for anything today, just work. I posted the KOEO codes, balance test and other codes soon.

Sounds like closed-loop issues - 14.7:1 is too lean for your engine for some reason. The computer should be able to compensate for a small, steady vacuum leak, but if it's already compensating to the max of its abilities (10-11% from base fuel tables), you could be running too lean. Of course, timing and everything else also changes in closed-loop - Some of the timing side can be tested by seeing if the 90-second thing still happens while the SPOUT plug is removed from the wiring at the distributor. You should be able to reproduce the 90-second closed-loop switch simply by idling in neutral. How the engine runs will noticeably change.

I'm dealing with the opposite issues - my car runs better the hotter it gets and the longer it runs. Runs worse when cold. Whatever I find as the culprit on mine, do the opposite on yours! :p
1988 Thunderbird Sport

Rocker adjustment....

Reply #128
I'll let it run a bit in neutral and see what happens. I gotta get the KOER test done and a balance test done. I'm going to triple check vacuum leak stuff as soon as possible. News as it happens. Codes as I get them.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Rocker adjustment....

Reply #129
Quote from: vinnietbird;440445
I'll let it run a bit in neutral and see what happens. I gotta get the KOER test done and a balance test done. I'm going to triple check vacuum leak stuff as soon as possible. News as it happens. Codes as I get them.

I've found that vacuum leaks can be pretty much impossible to detect, if they are small enough and/or numerous enough. After I fixed some extremely minor leaks, my EGR started to show leakage - and it's an almost new Motorcraft unit! It seems I can force a leak at almost any spot by simply pushing 20psi into the intake system. Normally I'd expect leakage at a capped-off throttle body, but with a stronger seal, the air finds other ways to exit the motor. This is an area where carb WOULD be easier - far fewer spots where leaks can occur!

I believe the intake should be able to hold 20psi without a problem. My leaks have gone from 1psi to 5psi holding, by fixing some leaks. Obviously I have more, but they are getting more difficult to find as the holding pressure goes up. I have no idea how much the seals in the block can handle.
1988 Thunderbird Sport

Rocker adjustment....

Reply #130
First off setting to a lower voltage brings the ECM in to WOT at a lower throttle opening. Base Plus 2.71. Simple math will tell yopu that the ECM calculates WOT voltage from closed throttle TPS plus 2.71. So the higher the TPS at closed throttle the higher the WOT nunbers gets. Or the higher the throttle opening angle. That is why newer OBD2 computers give you throttle angle along with voltage. The ECM does not use 100% throttle angle for WOT readings or lets say 5.0Volts. It uses base Plus 2.71 has been this way forever and that is why i set low. According to ford anything from .55- 1.1 is OK. Ses is set parameters are i think .48-1.13. Lower than .48 or higher than 1.13 and you get a code. So the mith that you should be as close to 1.0 is just that a myth. and it hurts performance. Bottom line is set min idle to 700-750 with the IAC disconnected and the tps @ .60 and then hook the IAC up and drive the car to learn the new settings. never use the Min idle adjustment for base idle. So many people mess this up and do not know how to set min idle and TPS. That is why Ford made the TPS non adjustable on the 302. But i slot the sensor to make my WOT come in earlier with a lower TPS base closed throttle setting.So if you engine is started with a TPS setting of lets say around .60 It concludes its WOT setting everytime at approximately the same number 3.31 Volts.  OK clear enough!!
I spend money I don't have, To build  cars I don't need, To impress people I don't know

HAVE YOU DRIVEN A FORD LATELY!!

Rocker adjustment....

Reply #131
Quote
Simple math will tell yopu that the ECM calculates WOT voltage from closed throttle TPS plus 2.71. So the higher the TPS at closed throttle the higher the WOT nunbers gets.


Yes.  I am pretty certain we're all in agreement on this.  It's basic math.

Quote
Ses is set parameters are i think .48-1.13. Lower than .48 or higher than 1.13 and you get a code. So the mith that you should be as close to 1.0 is just that a myth


From what I understand the voltages are .5-1.19, but yes we're in agreement AGAIN.

Quote
First off setting to a lower voltage brings the ECM in to WOT at a lower throttle opening. Base Plus 2.71.


Changing the start point voltage WILL NOT change how far the throttle needs to be open to achieve the WOT strategy.  It will simply change the voltage seen.  Ford TPS sensors deliver a linear signal.  That is to say move it from the start position to say a 45 degree angle of opening, you will see x amount of voltage over the start voltage whether it be .6v, 1.0v, .777777v, whatever.... It will be whatever you started with PLUS X volts at that same 45 degree opening. 

If setting the TPS voltage with throttle closed to the lowest value caused WOT to come in at a lower throttle angle every myth concerning the TPS would most likely have stated to shoot for .5v and not the holy grail .99v  PLUS this basically contradicts the rest of what you stated.

As per the GUFB:

Quote
OVERVIEW
 The throttle mode scheduler is used to determine what engine operating
 region is currently extant. The variable APT (At Part Throttle flag) is used
 to indicate throttle mode and is assigned the following values:
 Throttle Mode APT
 ------------------ ---
 CLOSED THROTTLE -1
 PART THROTTLE 0
 WIDE OPEN THROTTLE 1
 The value of APT is determined by the logic shown on the following page.
 Briefly, throttle angle breakpoints, in terms of counts, are used to define
 the CLOSED/PART_THROTTLE and PART/WIDE_OPEN_THROTTLE transitions. Hysteresis
 is incorporated in both breakpoints to prevent jitter between modes.
 The variable RATCH is the output of a ratchet algorithm which continuously
 seeks the minimum throttle angle corresponding to a CLOSED THROTTLE position.
 This alleviates the necessity to set the throttle position sensor at an
 absolute position and compensates for system changes and differences between
 vehicles. The ratchet algorithm uses filtered throttle position for the
 determination of RATCH.
 A more detailed explanation of the throttle position ratchets and throttle
 position filter is contained in the SYSTEM EQUATIONS section




-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!

Rocker adjustment....

Reply #132
Yeah, the sweep of the tps will be ~3.5Volts from closed to fully open - the throttle MUST open the SAME amount to reach WOT, no matter what the base Voltage is set to.

Also, 700rpm of idle isn't correct for a stock tune either. The EEC wants to see something closer to 600-624rpms base idle. In DRIVE, the EEC will try to reach 624rpms.

See attachment - stock tune. You can also see the next setting that is used for telling the EEC how much air is entering the motor at idle. A bit redundant with the MAF sensor, but it's there.

http://eectuning.org/forums/viewtopic.php?t=17439
1988 Thunderbird Sport

Rocker adjustment....

Reply #133
My cam is not stock by any means. I really doubt it could idle that low. Maybe I'm wrong. As of now, it wants between 800 to 900 rpms.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Rocker adjustment....

Reply #134
Quote from: vinnietbird;440457
My cam is not stock by any means. I really doubt it could idle that low. Maybe I'm wrong. As of now, it wants between 800 to 900 rpms.

That's fine - just saying that shooting for 700-750 as a base guideline isn't correct. I've idled as low as 500rpms years ago; any lower and the car would start to have problems and surge (EEC trying to keep the motor running with the IAC). You may be able to idle lower (if you cared) after getting all the other variables worked out. Like everyone always says - it's all about the total package, not just various parts thrown together.

The EEC also has settings for max idle in drive. I haven't played with this, but it is set to 824rpms. I'm not sure how/if the EEC compensates idle with the IAC when your base rpm's are already this high. There are a lot of settings that allow the computer to add even more air from the IAC.
1988 Thunderbird Sport