A6 with 3.7 diff gears problem

[Tre-Cool]

Hello, my car has a 3.7 diff gear and the engine tune has been modified to correct the speedo on the dash, however no matter what i change in the auto calibration the speed being logged via efilive is around 28% (more) out of what the dash is showing.

As such all the VSS and RPM shift points have to be calculated off this 28% outage.

For example:
1st to 2nd change: Cal = 60kph.
Actual speed shift changes at is around: 46kph
5th to 6th: cal = 96kph
actual speed = 80kph

Is this a known problem with the A6 calibrations? coz it makes it hard when trying to log the auto and to perfect shift time for the drags.

I want to get this working properly as i have a circle'd 3500 stall coming for it.

LABELS Gear Change
TPS . 1->2 2->3 3->4 4->5 5->6 2->1 3->2 4->3 5->4 6->5
0 44.000000 94.000000 153.000000 211.000000 511.000000 40.000000 89.000000 147.000000 205.000000 506.000000
100 44.000000 94.000000 153.000000 211.000000 511.000000 40.000000 89.000000 147.000000 205.000000 506.000000

[Chuck CoW]

Hello, my car has a 3.7 diff gear and the engine tune has been modified to correct the speedo on the dash, however no matter what i change in the auto calibration the speed being logged via efilive is around 28% (more) out of what the dash is showing.

As such all the VSS and RPM shift points have to be calculated off this 28% outage.

For example:
1st to 2nd change: Cal = 60kph.
Actual speed shift changes at is around: 46kph
5th to 6th: cal = 96kph
actual speed = 80kph

Is this a known problem with the A6 calibrations? coz it makes it hard when trying to log the auto and to perfect shift time for the drags.

I want to get this working properly as i have a circle'd 3500 stall coming for it.

Would prefer to email tune to efilive than post on forum.



Hey man... Call me.

Chuck CoW

[gmh308]

Hello, my car has a 3.7 diff gear and the engine tune has been modified to correct the speedo on the dash, however no matter what i change in the auto calibration the speed being logged via efilive is around 28% (more) out of what the dash is showing.

As such all the VSS and RPM shift points have to be calculated off this 28% outage.

For example:
1st to 2nd change: Cal = 60kph.
Actual speed shift changes at is around: 46kph
5th to 6th: cal = 96kph
actual speed = 80kph

Is this a known problem with the A6 calibrations? coz it makes it hard when trying to log the auto and to perfect shift time for the drags.

I want to get this working properly as i have a circle'd 3500 stall coming for it.

Would prefer to email tune to efilive than post on forum.


Did you change the trans speedo segment too?

[Redline Motorsports]

I wish EFI Live would finally address the transmission speedo issue that have been going on for 4 years! Not quite sure why getting a speedo calibration to work is not a priority to a properly functioning software.....

You ever have an issue with that Chuck.................:doh2:

[Tre-Cool]

Did you change the trans speedo segment too?
yeah, but it makes no difference what you set the values too. logging speed is still out of whack.

These are the current TCM values.
LABELS Vehicle Speed Sensor Pulses per Revolution
Parameters Value
{H0101} Vehicle Speed Sensor Pulses per Kilometer 24777.168593 Pulses/Km
{H0102} Vehicle Speed Sensor Pulses per Revolution 36.000000 .
{H0103} Final Drive Ratio 2.900024 Ratio
{H0136} Tire Revolutions Per Kilometer 468.000000 Revs/Km

this is from the ecm.
LABELS Non Driven Wheel Pulses Per Rev
Parameters Value
{H0101} Vehicle Speed Sensor Pulses per Kilometer 24777.168593 Pulses/Km
{H0102} Vehicle Speed Sensor Pulses per Revolution 36.000000 .
{H0104} Trans Output Shaft Revs/Kilometer 468.484435 Revs/Km
{H0135} Tire Size Correction 0.000000 Factor
{H0136} Tire Revolutions Per Kilometer 468.468750 Revs/Km
{H0139} Driven Wheel Rolling Circumference 2090.000000 mm
{H0140} Non Driven Wheel Rolling Circumference 2090.000000 mm
{H0152} Driven Wheel Pulses Per Rev 48.000000 .
{H0153} Non Driven Wheel Pulses Per Rev 48.000000 .
{H0159} Vehicle Speed Output Signal Yes
LABELS Final Drive Ratio
Parameters Value
{H0103} Final Drive Ratio 3.729980 Ratio
{H0120} Final Chain Ratio 1.000000 Ratio
{H0121} 4WD Low Ratio 2.000000 Ratio
{H0122} Axle Ratio 3.729980 Ratio
{H0123} 2 Speed Axle Low Ratio 2.000000 Ratio
{H0125} Front Axle Drive Ratio 3.000000 Ratio

I sent both the ecm and tcm tune to blacky last night so hopefully he might have a fix for me.

Obviously you can see i have 2.90 ratio in for the tcm but that's because it didnt make any difference to the true speed during logging. i just left on the stock setting.

[gmh308]

Dont know what size your tyres are, but the PPK seems to be incorrect. Would've expected something more like 60-70k.

It is a VE right? Speedo handled very differently in VE. :shock:


yeah, but it makes no difference what you set the values too. logging speed is still out of whack.

These are the current TCM values.
LABELS Vehicle Speed Sensor Pulses per Revolution
Parameters Value
{H0101} Vehicle Speed Sensor Pulses per Kilometer 24777.168593 Pulses/Km
{H0102} Vehicle Speed Sensor Pulses per Revolution 36.000000 .
{H0103} Final Drive Ratio 2.900024 Ratio
{H0136} Tire Revolutions Per Kilometer 468.000000 Revs/Km

this is from the ecm.
LABELS Non Driven Wheel Pulses Per Rev
Parameters Value
{H0101} Vehicle Speed Sensor Pulses per Kilometer 24777.168593 Pulses/Km
{H0102} Vehicle Speed Sensor Pulses per Revolution 36.000000 .
{H0104} Trans Output Shaft Revs/Kilometer 468.484435 Revs/Km
{H0135} Tire Size Correction 0.000000 Factor
{H0136} Tire Revolutions Per Kilometer 468.468750 Revs/Km
{H0139} Driven Wheel Rolling Circumference 2090.000000 mm
{H0140} Non Driven Wheel Rolling Circumference 2090.000000 mm
{H0152} Driven Wheel Pulses Per Rev 48.000000 .
{H0153} Non Driven Wheel Pulses Per Rev 48.000000 .
{H0159} Vehicle Speed Output Signal Yes
LABELS Final Drive Ratio
Parameters Value
{H0103} Final Drive Ratio 3.729980 Ratio
{H0120} Final Chain Ratio 1.000000 Ratio
{H0121} 4WD Low Ratio 2.000000 Ratio
{H0122} Axle Ratio 3.729980 Ratio
{H0123} 2 Speed Axle Low Ratio 2.000000 Ratio
{H0125} Front Axle Drive Ratio 3.000000 Ratio

I sent both the ecm and tcm tune to blacky last night so hopefully he might have a fix for me.

Obviously you can see i have 2.90 ratio in for the tcm but that's because it didnt make any difference to the true speed during logging. i just left on the stock setting.

[Tre-Cool]

it has 20" rims on it.

yeah it's a ve. Used to be delco's ride. which is why i havent posted the tunes.

[gmh308]

it has 20" rims on it.

yeah it's a ve. Used to be delco's ride. which is why i havent posted the tunes.

Heh heh :grin:.

275/35/20's or thereabouts?

[Tre-Cool]

Heh heh :grin:.

275/35/20's or thereabouts?
Somem like that.

http://www.vyssute.com/downloads/My%20photos/Photoshoot%20001%20(Large).jpg

http://www.vyssute.com/downloads/My%20photos/Photoshoot%20002%20(Large).jpg
Can't go wrong with a set of fatties on the back.

[gmh308]

Somem like that.

Can't go wrong with a set of fatties on the back.

VERY nice. :grin: Car and wheels! These are just great looking cars! :hihi:

Is there a rear wheel kw number those fatties need to deal with?

At 275/35/20, PPK calculate out to about 61k.

[Tre-Cool]

VERY nice. :grin: Car and wheels! These are just great looking cars! :hihi:

Is there a rear wheel kw number those fatties need to deal with?

At 275/35/20, PPK calculate out to about 61k.
i havent had it on the dyno myself, but i believe it made close to 300rwkw.

With a set of 17" Sv8 wheels and Mickey thompsons it ran a 12.1 last weekend at the perth motorplex with 1.9 -60's. hoping to get down to 1.5, 1.6 with the 3500 stall. but i might swap the diff from my brothers manual to drop the revs down on the highway and to give 1st gear a bit more usefulness.

[gmh308]

i havent had it on the dyno myself, but i believe it made close to 300rwkw.

With a set of 17" Sv8 wheels and Mickey thompsons it ran a 12.1 last weekend at the perth motorplex with 1.9 -60's. hoping to get down to 1.5, 1.6 with the 3500 stall. but i might swap the diff from my brothers manual to drop the revs down on the highway and to give 1st gear a bit more usefulness.

Cool. :rockon: How was the air this time of year?

Enjoy the hi stall! :shock:

[Tre-Cool]

Hello efilive support.. anyone home?

[vxchev8]

did you flash the tcm with the correct diff ratio and wheel sizes?

[Tre-Cool]

yes and it makes no difference. which is why im wanting someone to tell me why and when it'll work.

[Blacky]

I have the files, I have looked at them but can't see anything obvious. I have a VE here that I will be testing on but right now the priority is to get the AutoCal Beta test underway. I will get back to this later in the week.

The first thing I will try (and feel free to try it now), is to ignore the speedo calculator and put the speedo setting back to stock for that operating system. Then adjust the tire sizes in both the ECM and TCM to match the actual tire size.

Regards
Paul

[ScarabEpic22]

Oh man I want one of those rides, looks like the US G8? Id prefer the bowtie badge over the Pontiac one but short of importing on from down under doubt that'll ever happen. Biggest prob is the left hand drive. and money

[Tre-Cool]

are there any plans for getting access to more of the t43 a6 calibrations?

i've been browsing the hptuners forum and it appears there product has more available settings...

[Blacky]

are there any plans for getting access to more of the t43 a6 calibrations?

i've been browsing the hptuners forum and it appears there product has more available settings...

There's a bunch of updates for the Allison 6 speed and T43 6 speed, new PIDs (Ali6 and T43), new calibrations (T43 only) in the next update. I was going to release it this weekend but unexpectedly got called out of town for the weekend. I'm back now and I am packaging it up over the next 24 hours. Do a "check for new updates" in about 24 hours time (Monday morning US time) and you should get the update.

For this next update (and future updates) I am going to put up a web page that lists the updates available so you can see what you're getting before the "Check for Updates" downloads and installs the update.

Regards
Paul

[Tre-Cool]

great to hear. might be able to tune out the slow 3rd gear shifts.

[Tre-Cool]

Okay updated tonight. have noticed a couple of new fields etc. not as much as i had hoped for but ohh well.

one thing i did notice was 2 new options under torque converter. D2251 & D2252 - no caption yet.

i presume that means it's a table that you dont know what it does yet? :lol:

[GMPX]

They are pressure tables relating to torque converter lockup, once I added them there was a few calibrations where it looked wrong so I was supposed to remove them before releasing those calibrations so I could figure out what was going on......guess who forgot!
The plan wasn't to make you guys guess what they were.

EDIT: I just noticed some OS's had a lot of the new additions left out, looks like the 2006/07 T43 calz files will be updated again in the next day or so, sorry about that.

Cheers,
Ross

[Tre-Cool]

i also noticed alot of the existing tables etc were updated/changed as well. so it looks very promising.

Cheers

[gmh308]

And the PID coverage now appears outstanding! Just need to get some time to get them sorted and running on the V2.

Will any of the DVT controls end up on the V2 eventually? Also maybe Fast Learn on the A6?

Cheers and thanks guys!

:cheers:

[Tre-Cool]

looks like the speed is working properly now. just changed the ratio to 3.73 and noticed on the way to work shifts were holding on too long. i.e i wouldnt hit 6th gear till 118kph.

realised something was wrong so i jumped into the tune and realised that the tables were still set at the higher values for the 2.92 ratio.

Just found then that i had also put in a 2 second shift change for 2-3rd. haha. should have been .200

that'll teach me for playing with the tune after midnight.

[Tre-Cool]

ok. looks like there is still a problem with some calculations in the scan tool. if i log via the t43 controller the speedo is out 25%. log via the e38 and its correct.

also what tps pid am i supposed to use when logging under the trans. i have tried all the obvius 1s and get invalid pid for all of them. yet sometimes i will get data showing up during logging.

[Blacky]

ok. looks like there is still a problem with some calculations in the scan tool. if i log via the t43 controller the speedo is out 25%. log via the e38 and its correct.

Is H0103 set to the correct diff ratio in both the engine and trans calibrations? In the files you sent earlier, the engine tune is set to 3.73 and the trans is set to 2.90 - a difference of about 28%.


also what tps pid am i supposed to use when logging under the trans. i have tried all the obvius 1s and get invalid pid for all of them. yet sometimes i will get data showing up during logging.

Have you tried SAE.TP? (I know its obvious, but I would expect that one to be supported).

Regards
Paul

[Tre-Cool]

yeah, trans and engine are same values now. that fixed the problem with shifts having to be adjusted to the magical 20+% figure.

shifts happen when they should etc, but i still have the logging problem. Which now makes me think it was 2 seperate problems. 1 was the tune was set for wrong diff ratio and 2 the scantool is calculating wrong.

Problem with sae.tp is that it max's out at 88.2% tps so i never tried it.

[oztracktuning]

Email me the files Trecool and i will compare them to ones i have done that have the 3.70 gears. They are recording things correctly.

[Tre-Cool]

No need mate. I cant see how having the same values for both the ecm/tcm can result in different readings. So it's gotta be a calculation issue with a pid.

[oztracktuning]

You need to change the value in H101 if you havent already.
Im seeing correct values being logged

[Tre-Cool]

gimme 15 minutes, and i'll put a screenshot up of tcm/ecm.

just having lunch at the moment. :-)

[Tre-Cool]

http://www.vyssute.com/downloads/ve-stall-install/speedo-problem.JPG

My car might have an earlier tcm than your Oz?

[Blacky]

How different are the TCM VSS and the ECM VSS?

A wheel setting of 468 revs per km will have a circumference of 2136mm not 2090mm, since a km has 1 million mm), then 1,000,000/468=2136. However that would only give a difference of about 2%

Regards
Paul

[Tre-Cool]

How different are the TCM VSS and the ECM VSS?

A wheel setting of 468 revs per km will have a circumference of 2136mm not 2090mm, since a km has 1 million mm), then 1,000,000/468=2136. However that would only give a difference of about 2%

Regards
Paul
100kph on dash = 125kph in scanning logs.

My dash is purposely out by about 2kph for speed camera's and coppers. i.e see 70kph, actually doing 68.

[Blacky]

Maybe I misunderstood the problem.
I thought the problem was when you logged VSS from the ECM it reported a different value that when you logged the VSS from the TCM.

Now I think what you are saying is the speedo on the dash reads correctly (at 100kmh), but that the scan tool shows 125 kmh. Is that right?

If so, you can adjust the speedo on the dash using H0105, without affecting the internal speed of the ECM. H0105 is the speed output signal from the ECM to the dash.

So you could try re-adjusting H0136, in the ECM and TCM (and H0139 and H0140 in the ECM to match H0136, based on the formula in my last post), until the speed is reading correctly in the scan tool.

Then use H0105 to adjust the speedo needle on the dash.

Regards
Paul

[Tre-Cool]

Maybe I misunderstood the problem.
I thought the problem was when you logged VSS from the ECM it reported a different value that when you logged the VSS from the TCM.

Now I think what you are saying is the speedo on the dash reads correctly (at 100kmh), but that the scan tool shows 125 kmh. Is that right?

If so, you can adjust the speedo on the dash using H0105, without affecting the internal speed of the ECM. H0105 is the speed output signal from the ECM to the dash.

So you could try re-adjusting H0136, in the ECM and TCM (and H0139 and H0140 in the ECM to match H0136, based on the formula in my last post), until the speed is reading correctly in the scan tool.

Then use H0105 to adjust the speedo needle on the dash.

Regards
Paul
Dash shows 100kph. logging via ecm = 100kmh.
log via tcm = 125kph.

yet the values are the same for both tcm & ecm.

even the tcm runs off the ecm's kph for gear changes which is what confuses the shit out of me.

i'd rather not have to touch the tune in the ecm as i will loose a license. Dan knows more about tuning these engines than i do, so i dont touch it. :-) playing with the auto to suit my driving is different. :-)

[Blacky]

Can you send me the two tunes as they are right now and I will stick them in some controllers here and figure it out. (paul@efilive.com)

Regards
Paul

[Tre-Cool]

Emailed them through to support along with 2 log files. 1 logged via each controller.

in the tcm log you will see speed is sitting on 120kph, when in fact i was only doing 97~100 at the time.

[gmh308]

Does H0101 pulses per km make any difference to the outcome?

The PPK work out to about 65,000 or so (depending on actual rolling dia of tyre, 65,000 ~= 26" diameter tyres with 3.73 rear gear), whereas the paste in above shows something down in the 24,000-25,000 PPK range.

Oztrack points to this as well.

:shock:

[Blacky]

Does H0101 pulses per km make any difference to the outcome?

The PPK work out to about 65,000 or so (depending on actual rolling dia of tyre, 65,000 ~= 26" diameter tyres with 3.73 rear gear), whereas the paste in above shows something down in the 24,000-25,000 PPK range.

Oztrack points to this as well.

:shock:

I don't have a perfect answer for that. Some controllers appear to use it, some do not. The only way to know for sure is to change it (significantly) and observe the change (or lack of change) to the VSS PID.

Regards
Paul

[Tre-Cool]

im going back to the stock diff today, so it will be interesting to see if i still get this wierd 20% difference once i load the stock cal info back in.

[Chuck CoW]

Dash shows 100kph. logging via ecm = 100kmh.
log via tcm = 125kph.

i'd rather not have to touch the tune in the ecm as i will loose a license. Dan knows more about tuning these engines than i do, so i dont touch it. :-)

Uh HO.... I see a problem...... YOU DIDN'T TOUCH THE ENGINE CAL???

Ok, here goes... I've likely changed just somewhere short of a million differentials in A6 vehicles.....Mostly Vettes.

Honestly, I don't use EFI LIVE (yet) to do the complete speedo conversion for diff swaps.

But, 2 weeks ago, I did use EFI LIVE to convert a 3.73 A6 silverado TOW TRUCK to 4.56 gears. It's now the fastest TOW TRUCK IN THE BRONX!

Now, after installing hi-ratio diffs in A6 cars....you'll (like I've been suffering without help for years with in A4 cars) hit the rev limiter on WOT shifts if you don't modify the speedo parameters in the ENGINE cal.

From what I've played with, the speedo reported to the dash comes from (in vettes) the engine cal and not the TCM cal if I remember correctly.

Additionally, there are (i forget the cal #s) 2 parameters in the engine "speedo" cal that must be set to "1" or the car will not WOT shift. The first is the "FRONT DIFF RATIO" cal and I forget the other. but, it appears they are used in PCM related torque calculations and if you put anything else in those 2 cells except a "1" the car will not WOT shift.

Most Vettes don't have 4WD or a front diff for that matter and after hitting the rev limiter 1 million times at WOT I decided to change those values and MAN, YOU GOTTA SEE A 3.42 A6 CORVETTE GO WHEN WORKING CORRECTLY.

Right now, I've got a 3.90 equippt supercharged A4 corvette what won't shift at WOT....and several A4 C5s.

Anyone out there have any good info for me?:angel_innocent:

Chuck CoW

[Tre-Cool]

i posted a screenshot of the engine and trans cal in a page back Chuck.

They are both they same.

[oztracktuning]

H0136 in the stock calibrations exists in both the TCM file and the ECM file. But in my car the TCM one is 468.4 and the ECM is 503. What effect does this have on everything?

[oztracktuning]

Leave TM on, shift times low, adjust minimum timing table B5157 to fine tune TM on shift. They will change quicker with TM on and shift times/pressures increased (you know that Chuck!) and get shifts happening at WOT by commanding with speed dominating as early as needed. Drop the RPM to shift at WOT very low.

Having said that my 440rwkw (670dynojethp) TT 6L is shifting at 2-3 6100rpm/109kph when i command 5400rpm/95kph and thats with a CircleD 6L80e 3000 converter as well.

[Blacky]

H0136 in the stock calibrations exists in both the TCM file and the ECM file. But in my car the TCM one is 468.4 and the ECM is 503. What effect does this have on everything?

It will most likely cause the TCM to calculate a different speed than the ECM.
When the engine is seeing 100kmh, the trans would see 100*(468.4/503)=93kmh
(Assuming I got my math correct).

Regards
Paul

[oztracktuning]

The VE range all seem to have speedos that read about 4% higher than the logger sees.
Is this the reason?

[Blacky]

The VE range all seem to have speedos that read about 4% higher than the logger sees.
Is this the reason?

I'm pretty sure that H0105 controls the speed displayed by the speedo when H0159 is set to Yes. So you could change H0105 to change the speedo reading without affecting the value of the VSS PID in the ECM.

Regards
Paul

[gmh308]

All speedos read 3%+ high. Its either an industry standard (like SAE) or a regulation.

Have not seen VSS data on any car yet that is not a few % lower than the speedo.

Helps to prevent speeding fines and arguments about incorrect speedps :).

[Tre-Cool]

well simply changing all the 3.73 settings in the ecm/tcm to 2.92 again means i have had to increase the kph settings to suit the "longer" gears.

I havent done a tcm log only to see if it's out like before as i've just been using the BB logging to get both tcm & ecm data.

[Tre-Cool]

small update, now that im using bb logging for the ve, i can calibrate the tcm much easier. bb comes in very handy for racing at the strip.

[Redline Motorsports]

I have a XLR-V that we just installed 3.15's. How much BS do I have to go thru to get the trans cal scaled and working for this change?

Has this posted issue been addressed? Is the speedo calulator working correct or not?

Howard

[Blacky]

I have a XLR-V that we just installed 3.15's. How much BS do I have to go thru to get the trans cal scaled and working for this change?

Has this posted issue been addressed? Is the speedo calulator working correct or not?

Howard

Don't rely on the speedo calculator for E38/T43 setups.
Just manually adjust the tire size and gear sizes based on what you've changed.

Regards
Paul

[Tre-Cool]

I have a XLR-V that we just installed 3.15's. How much BS do I have to go thru to get the trans cal scaled and working for this change?

Has this posted issue been addressed? Is the speedo calulator working correct or not?

Howard
what sort of diff does the xlr-v use, is it compatable with the G8's?

[Redline Motorsports]

what sort of diff does the xlr-v use, is it compatable with the G8's?

The XLR-V is built on the Corvette chassis. Same rear minus a few differences.......different side cases, etc.....

Paul,

Manually make the changes...........