2nd Time at the Track-Possible Converter Issue?

KStromberg

KStromberg

VIII looking for 8s
I hit the track for the second time this last Saturday and unfortunately I encountered a couple problems. The first one being the heat. The temperature in the morning was 72 degrees and quickly climbed into the 80s. My best time was a 14.275 and that was in the morning when it was still in the 70s. Throughout the day, the car seemed to get slower and slower, and my average times were about 14.4

With the exception of the first two passes in the morning, I did all of my passes manually shifting which leads to the second problem which is more of a concern to me.

My buddy Dan and I decided to leave earlier than everyone else in hopes to get a few cooler morning passes in which paid off in a way because the temperatures quickly rose and my best time would have never been attained otherwise. It is about a 2 hour drive from his house to the track over in Eau Claire. As I am following him on the highway at about 70mph, I am noticing that the car feels as if it is on the very edge of "lock-unlock" in the torque converter. The rpms as we are at 70 mph are fluctuating back and forth about 100 rpms on the tachometer and the converter almost seems to be locking-unlocking. I should have payed more attention, but couldn't say if it had anything to do with throttle input or not considering the highway wasn't completely flat and I wasn't using my cruise control.

As we turn into town off the main highway we get on the offramp and approach a yield sign going to the right, Dan slows down and then as there is no traffic this early in the morning he gets on it wide open throttle and I do the same behind him. The car shifts awesome out of first into second gear, and then all of a sudden, the car drops out the rpms and then downshifts again causing this big gap where the car isn't even accelerating and then the power comes back and it proceeds to accelerate:eek::confused:

This is precisely what happened at the track on my first two passes which almost made me want to turn around and go home right there, but I toughed it out and manually shifted the car. I am also wondering if the tuner this last week messed with something torque-converter related in the tune in an attempt to solve the "warble" that I told him about with my dyno graph earlier this year. Either way, the problem is VERY pronounced when I did my first two runs at the track.

I tried to make some videos this evening from a dig and going onto an onramp but the car wouldn't do it. :confused:
 
1st thing I would check is the chip connection and make sure it is taped in place.

Could be a myriad of things, hopefully just a shaky connection somewhere to the TCC solenoid.

The best way to tell if it is locking properly at speed is on the highway with the cruise control. Once at cruise speed, tap the set button once or twice to pick up the speed a tad. If the rpms build then fall back, the converter is not locked. If the rpms simply go up a touch along with the speed, the TC is locked.

You really need to stop manually shifting.
 
driller said:
1st thing I would check is the chip connection and make sure it is taped in place.

Could be a myriad of things, hopefully just a shaky connection somewhere to the TCC solenoid.

The best way to tell if it is locking properly at speed is on the highway with the cruise control. Once at cruise speed, tap the set button once or twice to pick up the speed a tad. If the rpms build then fall back, the converter is not locked. If the rpms simply go up a touch along with the speed, the TC is locked.

You really need to stop manually shifting.
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This I understand John. You have always been of great advice and I heed your warning. I personally did not want to manually shift the car, but when I do two passes and the car runs a 14.8 and does this terrible doubledownshift thing I figured something was not right in the tune so I figured I would try a different method and try to get a decent timeslip since I traveled 2 hours to the track. Hind sight is always 20/20, and if I could go back, I would have skipped this track outing altogether since it turned into a hot icky non track-friendly day.

One thing I do know is that before this next spring, I am going local. Whether or not this issue persists, the car is going to have to be dyno-tuned and data-logged. Even the tuner has been stumped at how many issues I seem to have been having, but really there hasn't been many.:rolleyes: He is just starting to know me by name. :D Really, the only two issues I've had was the stock transmission parameters which caused a driveability issue in the past, which turned out to be a bunk tranny of course, and now this potential lock-up issue I am having. Everything else has been changes that were either overlooked(rear o2s), or for example, the short-shifting with stock shift points. (Why would a tuner go with stock shift-points anyways on a 4-valve with full exhaust, gears, and a stall:confused:)

So here I am again. I sent the tune back yesterday for the last time before the snow flies and I go with my "local" option for tuning seeing that there is still one more track date at the end of October that I would like to make it to as long as the weather cooperates.

He said that he did not recall messing with any lock-up parameters in the tune this last time, but rather raising the shift points in first and second and turning off the rear o2 sensors. He says that there is no real definite way of knowing when the shift occurs EXACTLY in a tune without actually data-logging, but he tries to leave enough of a gap between when the unlock-lock occurs into gear and when the car actually shifts, if that makes sense:confused: If these conditions overlap each other, he says it MAY cause what I was experiencing where the rpms drop down from the converter locking up and then actually fall far enough below that threshold where the car wants to downshift again.

Whether or not this is true, one of my buddies told me that my car may not have enough power to pull through the lock-up and it may need to be turned off until a higher mph. I mentioned this to the tuner, and he says my 1/4 mile times and torque will suffer as a result. Although, this same buddy of mine claims that his lock-up isn't until almost 90 mph. He runs the same transmission in a built CVPI with cams, gears, stall, etc. The tuner claims that the tune is the way it is because of the design of the 4R70W. The converter has to unlock-lock into every gear.
 
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I don't know but I've been told you can indeed leave the converter locked through a shift - but the tranny better be up for the task. Turning the lock-up off is not the answer either, but altering the delay and the modulation is what is required to get the lock-up right.

Your shift point(s) may be too high. When I was track testing my shift points, I found too high would result in a double-clutch effect. I am probably 100 rpm below that as of now.

Track testing and/or data-logging is the only way to do it right and find that max rpm without going too far. But it takes time and patience, something us racers are short on a lot of times. ;)
 
I'd suggest getting the software, and making these changes yourself.

It far outweighs the "send it back, wait and retest" scenario.

as you determine what you want, and what you dont want/like" it makes it far easier to just make the changes yourself, than it is to try and communicate your wants/needs to a third party and HOPE they
1. understand what you want
2. actually do what you ask them to do

With transmission tuning, there are many areas that are PURELY personal preferences, on shift points, lock up schedules, lock up rates and such.
Many times there is no ONE right answer.

That is pretty much why I wound up with the software to tune it myself.

your likely "at that same point", where your personal preferences and what your tuner is willing to spend the time to "track down".

If the motor is making good power, not pinging, and driveability is good.
then get the software, and tweak the trans functions until they suit your needs/wants and desires.
 
XLRVIII said:
I'd suggest getting the software, and making these changes yourself.

It far outweighs the "send it back, wait and retest" scenario.

as you determine what you want, and what you dont want/like" it makes it far easier to just make the changes yourself, than it is to try and communicate your wants/needs to a third party and HOPE they
1. understand what you want
2. actually do what you ask them to do

With transmission tuning, there are many areas that are PURELY personal preferences, on shift points, lock up schedules, lock up rates and such.
Many times there is no ONE right answer.

That is pretty much why I wound up with the software to tune it myself.

your likely "at that same point", where your personal preferences and what your tuner is willing to spend the time to "track down".

If the motor is making good power, not pinging, and driveability is good.
then get the software, and tweak the trans functions until they suit your needs/wants and desires.
Click to expand...

This is all very true and trust me, things will change before next spring. I totally understand the reasoning here and if I could go back, I would have done things all different as far as my tuning options. Yes, XLRVIII, driveability seems to be up to par and the engine still seems healthy. BUT, this hiccup with the converter was alarming to me when it happened and really isn't a matter of me being "at that point" of personal preference. I simply need the car to shift properly:eek: It's definitely not right and is an ERRONEOUS condition in the tuning unless of course, my converter decides to let go on me in the near future. Let's all keep in mind, this converter was in a bunk tranny that had toasted clutch packs but I believe the converter was sufficiently drained for a few days and there was no metal in the pan from what I could see....just clutch material. I have had this newer trans for about a month now with no problems whatsoever. This condition did not start until after my tune was sent back with raised shift points.

John, can you clarify about the shift points possibly being too high? I believe our own DLF has a Stage 1 3600 stall and his car shifts at 7000rpm in first gear. And I have seen several fellow 8s on the tube that all have a first gear shift point at 7000k rpm.....I don't see what my problem is. I'm only at 6500 :confused:
 
KStromberg said:
John, can you clarify about the shift points possibly being too high? I believe our own DLF has a Stage 1 3600 stall and his car shifts at 7000rpm in first gear. And I have seen several fellow 8s on the tube that all have a first gear shift point at 7000k rpm.....I don't see what my problem is. I'm only at 6500 :confused:
Click to expand...

Oh I know more than a couple guys shifting well above stock.

First thing to understand is the lag between the commanded shift and the actual shift. This is a function of the electrical and hydraulics of the transmission vs. the acceleration rate. I would say a commanded 1-2 shift at 6500 rpms is likely very close to an actual 7000 rpms. The 2-3 shift will have less lag time since the acceleration is lower.

When you consider acceleration is a function of gearing, torque multiplication, power, weight, tire size and several other factors you can begin to see why there is no "one size fits all" shift points for maximum performance.

Add to that the display error of the stock tachometer.

The sure way to see and understand the shift point is to datalog the car knowing the commanded shift points and then comparing them to the actual shift in the data record. The best way to determine the optimum shift point is to systematically test it at the track and examining the split times to determine the acceleration rate.

I am only relating the issues I saw on my car when tuning the shift points at the track. The caveat is I cannot datalog and determine the actual shift point and the cause and effect relationship which displayed itself when the shift points were obviously too high. I hope to remedy that, but until then it is only conjecture.
 
KStromberg said:
John, can you clarify about the shift points possibly being too high? I believe our own DLF has a Stage 1 3600 stall and his car shifts at 7000rpm in first gear. And I have seen several fellow 8s on the tube that all have a first gear shift point at 7000k rpm.....I don't see what my problem is. I'm only at 6500 :confused:
Click to expand...

FWIW, My commanded shift points for 1st/2nd and 2nd/3rd are 6100 and 6300, which result in the shifts actually occuring around 6700. I'll probably raise them a bit once I get the Cobra intake installed. Right now higher shifts result in slower times.
 
driller said:
Oh I know more than a couple guys shifting well above stock.

First thing to understand is the lag between the commanded shift and the actual shift. This is a function of the electrical and hydraulics of the transmission vs. the acceleration rate. I would say a commanded 1-2 shift at 6500 rpms is likely very close to an actual 7000 rpms. The 2-3 shift will have less lag time since the acceleration is lower.

When you consider acceleration is a function of gearing, torque multiplication, power, weight, tire size and several other factors you can begin to see why there is no "one size fits all" shift points for maximum performance.

Add to that the display error of the stock tachometer.

The sure way to see and understand the shift point is to datalog the car knowing the commanded shift points and then comparing them to the actual shift in the data record. The best way to determine the optimum shift point is to systematically test it at the track and examining the split times to determine the acceleration rate.

I am only relating the issues I saw on my car when tuning the shift points at the track. The caveat is I cannot datalog and determine the actual shift point and the cause and effect relationship which displayed itself when the shift points were obviously too high. I hope to remedy that, but until then it is only conjecture.
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Thanks John! Some clarification has been made. :)
 
DLF said:
FWIW, My commanded shift points for 1st/2nd and 2nd/3rd are 6100 and 6300, which result in the shifts actually occuring around 6700. I'll probably raise them a bit once I get the Cobra intake installed. Right now higher shifts result in slower times.
Click to expand...

Thanks Doug. Your bit of information is helping the clarification process too. I left my number in the package with my chip, so I expect the tuner to call me and I think one good first step just may be to have the shift points dropped.
 
Ever since I put a blower on my car, my WOT automatic shift trans tune never seemed to be right. I have had the best in the business look at my tune, and I still don't like it.

I agree with Tommy and JP, that the only way to get it right is tons of seat time tuning to get the automatic WOT shifting the way you want it. I have been trying off and on for something like 3 years now to get the WOT automatic shifting the way I like it, and my tuner's shop is 5 miles from my house with not much luck.

The manual shift tune I have in my car now, is the best solution I have had yet. It does what I want, when I want it. :)

I am not trying here to discount what everyone is posting about automatic shifting being the only way to run your car down the track, but manual shifting works for me. I wish I could leave it in drive.

I am not a bracket racer like Tommy and JP, so my way of thinking is a little different than theirs when I show up at the track. IMHO, I would foot brake bracket race a completely stock vehicle before a modified one any day if redundancy is what I was looking for.

Somehow, they manage to be consistent with their times, while I occasionally have a good day where one run to the next is within a tenth or two. Not sure what your plans are Kirk, but I compete in brackets once or twice a year, and T&T maybe four or five times a year. Not enough track time for me to be a serious bracket racer.

I suggest you put your trans tune back to the way it was when you ran that 14.2, and run the car in drive, or manual shift it if you like. If you are trying to squeeze another 10th out of it, try removing a 100 pounds from the car. It is way easier than trans tuning. :)
 
Stock 1-2 shifts are programmed for 5600 rpms.

Stock 2-3 shifts are programmed for 5850 rpms.

My 1-2 shifts are at commanded at 6300 and the 2-3 shift is set at 6450 with 4.30 gears and a 4200+ stall converter.

There are several parameters in the tune for the torque converter lockup and I am certain more are available with the OBD2 PCM. Converter delay, ramp and slip are the big three for the converter lockup.

Yeah, converter slip, imagine that.
 
KStromberg said:
For some reason J, I actually somewhat understand this comment although the converter issue is for the birds. :D
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Lol, you say it like I mumble a lot or something. If you drive a Ford, you'll notice, even at WOT, the transmission will slip into gear for a split second and then "thump" when the gears actually engage.
 
J said:
Lol, you say it like I mumble a lot or something. If you drive a Ford, you'll notice, even at WOT, the transmission will slip into gear for a split second and then "thump" when the gears actually engage.
Click to expand...

The shifts on my '93 at WOT are a very hard THUMP! :D
 
Well YA....because you JMod'd (and more) your trans, lol. Mine thumped good and sometimes scratched 3rd! :D
 
J said:
Lol, you say it like I mumble a lot or something. If you drive a Ford, you'll notice, even at WOT, the transmission will slip into gear for a split second and then "thump" when the gears actually engage.
Click to expand...

Lol. You are too funny J. If your modified Mark VIII is still sliding into gear, you have problems. The first thing I noticed after my mods, particularly the JMOD and tune, was the snappy shifts and lack of slip like I had before. Wasn't that the whole concept of the JMOD anyways :confused:

Reflecting back on your posts on my threads(which have all been cocky), although there are few, I would just like to say one thing. When you get on this forum, you have no badge. No need to be a wise-ass. :)
 
Naw, I was just more talking about all FORDS because after I was reading about the technical term for the shift when I worked at the transmission shop, I began noticing it when I drove them. Even the crown vics do it....it makes me laugh sometimes. My car had the transmission rebuilt right when I bought it and I also put the 3200 stall converter in it

Now listen here "boy" (LMAO! http://www.youtube.com/watch?v=QpQGcNLFppY)haha had to do it. If you knew me in person, you'd understand that all my posts are pretty much in a joking fashion and NOT in a cocky fashion. I definitally know my stuff when it comes to cars so I don't mess around, but I'm in NO WAY badge heavy. Sorry if you got that impression I really just like to make people laugh. Thats why I use the crap out of my smiley faces. :)
 
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