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Ruiner46

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I searched through the FSM and there's definitely data from the ABS wheel speed sensor system that's being used, but the speedometer is driven by the PCM which appears to be referencing the VSS. Below is an excerpt.

upload_2020-8-25_10-4-36.png
I don't see anything definitive there. It talks about vehicle speed signal users, but not specifically the speedometer. Tell you what, go program your Bowler harness with a value that is way off. Then go for a drive and see if your speedometer is affected. If it's a wheel sensor that is used, the speedo should still be accurate, but the VSS output will be way off.
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I don't see anything definitive there. It talks about vehicle speed signal users, but not specifically the speedometer. Tell you what, go program your Bowler harness with a value that is way off. Then go for a drive and see if your speedometer is affected. If it's a wheel sensor that is used, the speedo should still be accurate, but the VSS output will be way off.
With HPTuners and the Abbott box, this is what happens. VSS was set at 34 (and it is normally set at 34.0058). We then changed it to 12. Speedo, didn't change.
I have not had a chance to disconnect the power from the abbot box and give it a try.

Regards,
Dave
 

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upload_2020-8-25_12-40-22.png



From what I can tell PCM reads directly from the VSS and gets fed a signal from the ABS module via a gateway module (GWM).

The PCM checks for agreement within a range, some voodoo happens, and then outputs a vehicle speed signal to whatever needs it.

It probably prioritizes the wheel speed signal which makes the most sense. I'm sure disconnecting the VSS would just throw a code.
 

Ruiner46

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With HPTuners and the Abbott box, this is what happens. VSS was set at 34 (and it is normally set at 34.0058). We then changed it to 12. Speedo, didn't change.
I have not had a chance to disconnect the power from the abbot box and give it a try.

Regards,
Dave
When I said what I said about the power wire, I didn't mean to disconnect power to the Abbot box. I was saying that if you didn't have the Abbot box at all, you could wire the T56 sensor directly into the OEM wiring harness and change the pulses/rev value in the tune with HPTuners.

That way you don't have to rely on some box changing from 34 pulses to 12 pulses. The Ford PCM will just read directly from the T56 speed sensor. If you have HPTuners or a good tuner who knows what changes to make, then you don't need a conversion box or harness.

In my opinion, the only thing the Bowler harness is good for is controlling the reverse lockout. Tune changes already need to be made to handle the gear ratio differences, so why not handle the speed sensor conversion at the same time?
 
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Ruiner46

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upload_2020-8-25_12-40-22.png



From what I can tell PCM reads directly from the VSS and gets fed a signal from the ABS module via a gateway module (GWM).

The PCM checks for agreement within a range, some voodoo happens, and then outputs a vehicle speed signal to whatever needs it.

It probably prioritizes the wheel speed signal which makes the most sense. I'm sure disconnecting the VSS would just throw a code.
I agree with everything you said. I have never seen any documentation that indicates what system gets what signal. However, as others have reported in various threads on this site, the only change that seems to throw off the speedo is the tire size.

Now there may be more complicated things going on in the PCM code. For instance, there is something about the rear diff gear ratio being either stored in the BCM, or maybe learned through some calibration. In HPTuners there is a value for final drive ratio, but on my car it is set to 3.31 in the factory tune ( I have 3.73's). There is also a toggle for "Learn from BCM" or "Calibration". I think if I set the toggle to calibration, it will use the value in the tune, and if I have "Learn from BCM", then some magic is going on in the code to figure out what diff is installed. There are also min/max ranges and min/max for tire size. This obviously allows Ford to handle different tire/wheel and final drive combinations with a single tune. What I don't know is if there is some learning that goes on, perhaps comparing things like the transmission sensor to the wheel sensor.

Now if Ashtar's Abbot box is outputting a good signal, then when he changed between 34 and 12 pulses/rev and saw no difference in the speedometer, then this would indicate that the speedo itself is using the wheel sensor. We know for a fact that the PCM torque control is using the transmission sensor as the pulses/rev value and the gear ratio tables all have to be correct or you get strange behavior, and cruise control won't work. The Ford PCM uses torque control for everything throttle related, including drive by wire and traction/stability control so it makes sense that cruise control would use that system.
 

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Just showing off my QA-1 with sonnax flanges on each end. Will get a chance to run it up to speed on the weekend, but appearance quality is top notch.
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aleccolin

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No pics, but I feel like there's some good info here #walloftext #sorrynotsorry

So, a quick update on my heap. I've been in the middle of a move to a new place (huge shop!) and got just enough done to ferry the car over late one night, but need to get my lift reinstalled and get back to work asap.

I was finally able (I think) to successfully perform the crank relearn procedure after multiple attempts, updating my BDX, and ultimately just driving the car first without it. I haven't gotten back to it yet to confirm, but it was starting and idling fine last I was in the car.

It WAS doing the "rev hang" or whatever issue, on the 1-2 and 2-3 shifts (maybe 3-4 also) where it revs up to about 3k and holds it between shifts. Very unsettling feeling, but it also appeared to stop doing that after the car was driven about 20 minutes, so I don't know what the deal is there. If it persists, I may have to take it up to Richmond to my tuner unless he can fix that remotely.

My replacement Bowler harness is still acting all fucky. Reverse lockout solenoid operating intermittently and it's not showing up on Bluetooth so I don't know if it's even powering on. I thought it was a low voltage issue, which apparently they are sensitive to, but even after charging the battery and confirming it was getting proper voltage it's still very hit and miss. That's actually the exact phrase used by Bowler in reference to using the ECU to power the unit on the S550 (and probably S197) chassis Mustang, "hit and miss". Like, it's not a 100% reliable setup, so I honestly wish they would just update their instructions to REQUIRE running a dedicated switch 12V power and ground instead of just having that as an option. My plan is to try a jumper, if that works I'll rewire it all AGAIN and hopefully wind up with something as clean and tidy as what I have now.

Regarding the Tilton clutch, it works perfectly, no chatter or other noise, and the Tilton throwout as well, but I've only driven it once so far. Pedal feel is linear with takeup in the upper half of the travel, meaning a quick stab at the clutch is all it takes when rowing through the gears. It only takes around 1/4" of actuation (at the diaphragm fingers) to operate this clutch, and at full stroke you can feel a slight amount of overtravel at the bottom. The throw on the OE release bearing is even longer, so I'm going to say the Tilton or similar aftermarket HRB is a must with the ST-246 clutch. Pedal effort is, however, noticeably heavier than stock. I reinstalled the OE 185 lb/in pedal assist spring (that was a BITCH) which helped some, but it's still heavier than the OE clutch with the Steeda assist spring. Tilton told me pedal effort should be in the 40-50 lb range, which would have been good info to have before because that's about 2x the OEM (too soft) clutch feel. Since the Ram dual disc is known to reduce pedal effort some that's kinda what I was expecting, not what I got. Based on a test done by some due on YouTube, the stock pedal effort is approx 23 lbs max (non-linear). Effort with the Steeda 35 lb/in assist spring is around 32 lbs, still non-linear. My guesstimate of this clutch setup is probably about 10 lbs over that and much more linear, stiff but not unbearable. Similar to other performance single disc clutches I've had in past cars, you KNOW that it's a performance clutch when you drive it. I feel like it'll pair well with my blower setup when done, but it's a matter of preference. I wouldn't want to drive this in stop and go traffic every day, but it would be doable. Tilton said the clutch pedal effort would decrease a little as the clutch breaks in and the diaphragm springs take a set. I'll report back on that.

Regarding the trans, everything appears to be working well, no weird noise or vibration, only got it up to highway speeds maybe 70 mph, but I did the drive over without reassembling the interior so I had a big hole in the floor through which to hear anything that sounded expensive. So far no issues. My driveline angle with the poly spacers between the crossmember and body is well within a half degree which is what's recommended so I wasn't concerned about the driveshaft, but I'll still keep a close eye on things because the overall feel with this trans is very different than stock.

Regarding the shifter - I'm using the MGW and have come to learn that with OE and aftermarket T56 variant transmissions an aftermarket short shifter tends to highlight the notchiness of the shift feel, especially before the trans has broken in and it smooths out a bit. The lateral shift effort is increased, meaning it feels like the centering spring is too heavy and you're pushing harder than you should to get it over into the 1-2 and 5-6 gate. I thought about shimming the shifter detent plug, lo and behold that's exactly what many people do, for some reason calling it the "anti-venom mod". All this does is shim the shift detent plug out to decrease the detent strength to something closer to an OEM shifter feel, while also feeling less notchy I guess due to not having as much lateral pressure on the assembly. The maximum shim recommended is 1/8", so most use copper crush washers (Dorman 65277) which are about .060" each and you can use 1 or 2 shims to taste. I'm going to try this with mine, but it would have been SOOOOO much easier to do it BEFORE the install! It's one of those things I'd never have known about until experiencing it though and searching for solutions; nobody has time to read all the forum info that's out there.

In that same vein, the reverse detent spring pressure also feels higher with the short shifter, so Core Shifters sells a "soft" reverse lockout bias spring that is intended to replace one of the springs in the reverse lockout solenoid. I thought about deleting the reverse lockout, but I think the clearancing I did on the trans tunnel worked out pretty good so I'll keep it if I can. Since I'll have to lower the trans some to get to the detent, I'll just do the lockout spring at the same time.

That's it for now, hopefully I can get my lift reinstalled and get back to work soon.
 
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aleccolin

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The MGW shift lever actually puts the shift ball right about where the stock one is, just the action on the shifter is shorter. Don’t really want to make it longer/taller than stock.
 

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Ruiner46

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#walloftext
I think crank relearn problems will likely only show up at high RPM as misfires, so start-up and idle may still be fine. Speaking of high RPM, I didn't have any weird vibration issues until I rev'd above 5000RPM. I drove for a while taking it easy on the clutch, and had no vibrations up to 80mph on the highway. My car is currently torn apart to have the flywheel and clutch balance checked.

I noticed the rev hang was prominent on my car before I made the tune changes to correct the VSS pulse count. However, when I made the tune change, I also disabled the rev hang feature, so I'm not sure which thing fixed it. It could be that your bowler harness is operating intermittently for the VSS correction as well as the reverse lockout. It would be a good idea to datalog the VSS and see if the signal is flaky. Or test by running a dedicated power wire like you said. Just also be aware that if you don't like the rev hang feature, your tuner can turn it off.
 

aleccolin

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I think crank relearn problems will likely only show up at high RPM as misfires, so start-up and idle may still be fine. Speaking of high RPM, I didn't have any weird vibration issues until I rev'd above 5000RPM. I drove for a while taking it easy on the clutch, and had no vibrations up to 80mph on the highway. My car is currently torn apart to have the flywheel and clutch balance checked.
What was the runout on your flywheel? Mine was barely within spec, but the flywheel was perfect it was the OE signal rotor that was slightly out - a couple tenths in thickness variation quickly becomes a few thousandths at the outer edge of the flywheel. I tried to fix it by getting a billet signal rotor from MMR, but it was MUCH worse measuring around 8 though variance in thickness, and the manufacturing tolerances were so bad it was literally unusable (as in it wouldn't even go on without modification). If it had gone on, it would have put my shit WAAAY out of balance and probably wrecked the clutch, or worse.
 

Ruiner46

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What was the runout on your flywheel? Mine was barely within spec, but the flywheel was perfect it was the OE signal rotor that was slightly out - a couple tenths in thickness variation quickly becomes a few thousandths at the outer edge of the flywheel. I tried to fix it by getting a billet signal rotor from MMR, but it was MUCH worse measuring around 8 though variance in thickness, and the manufacturing tolerances were so bad it was literally unusable (as in it wouldn't even go on without modification). If it had gone on, it would have put my shit WAAAY out of balance and probably wrecked the clutch, or worse.
Oh no, I just got my MMR crank trigger delivered. I'll measure the runout on the stock piece and this one. I did notice the area around the pin seemed a little different in thickness since I can catch an edge with my fingernail. I don't have calipers to measure thickness, so I'll slap it on and measure the runout if I can find a good spot to mount the dial indicator base.

For the flywheel, I just took a measurement last night. Here is a video:


Looks like about 5 thousandths. What is the spec?
 

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Here is the OE trigger wheel - the variance in thickness was measuring in the ten-thousandths range, so effectively perfect since my micrometer is in hundredths.

RY6q5hil.jpg


Here is the MMR trigger wheel, the variance in thickness was 8 thou which would result in God knows how much runout at the flywheel, maybe 30 thou or more. The crank face was perfect zero runout and as far as I could tell without a surface plate, the Tilton flywheel was perfect too. I stoned the outside face to be sure there weren't any high spots and it was good. I believe the stock they used was fine, all of the error was in the setup or the program.

0ZqAM5Sl.jpg


This is the back side of the MMR trigger wheel, which was so fucked it wouldn't even go on the crank. The ID needed to be opened up about 4 thou with a flap wheel and even then, it wouldn't sit flush because the locating pin wasn't machined correctly and the "register" lip on the outside was larger than the bore of the hole in the crank. The edge of the hole in the crank is radiused slighly, so I was starting to try and figure out how to file down the lip on the locating pin before I decided to check the thickness and subsequently scrapped the idea and sent it back to MMR.

2o9qIQfl.jpg


I'll note that the only reason I got the MMR trigger wheel to begin with is because I had a little runout with the new flywheel and wanted to eliminate some error. I didn't do a great job of mic'ing the OE trigger wheel to begin with, so I thought that was the issue, but I was wrong. Got a better mic and rechecking the OE wheel it was perfect, no reason not to reuse. I believe the runout I was getting was due to not turning the motor over enough before starting to take measurements, so what I was reading was variance in oil film and thrust.
 

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Hello Magnum XL swappers! I'm planning my swap and most likely going to get everything through Modern Driveline. My car currently has a Whipple stage 2 kit on it running on the Whipple tune. I know tuning changes are needed to run the Magnum with the different gear ratios and a few other things.

I have zero complaints about the Whipple tune. Car makes great power and runs awesome. I've been debating what to do in regards to the tune and my question is around HP Tuners. I think I'd be comfortable making the tuning changes myself if someone can steer me in the right direction.

Does anyone here know exactly what needs to be changed if using HP tuners? I'm assuming gear ratios somewhere, but there is also talk about 'shift assist' and making cruise control work. Just trying to avoid having to go with a pricey third party tune. Appreciate any info!
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