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With 4.10's what RPM are you pulling at 80? And I'm sure it will do 80, but how strong does it pull from 65 up to 90-95?
Don't know what 80 is. I broke my spedometer, remember? :p

4.10s are ~3000 at 84.
There is a limiter at 3k (Same one you get at 105.
I cant' do past 84.
Need to put in the rest of my parts, and get a tune ;)

Stays locked up now until what feels like 75% throttle input in 4th. Pulls up to the the rev-limiter easily without scary rocketship noises. I don't ever really unlock the converter on the highway... don't really need to.
 

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Don't know what 80 is. I broke my spedometer, remember? :p

4.10s are ~3000 at 84.
There is a limiter at 3k (Same one you get at 105.
I cant' do past 84.
Need to put in the rest of my parts, and get a tune ;)

Stays locked up now until what feels like 75% throttle input in 4th. Pulls up to the the rev-limiter easily without scary rocketship noises. I don't ever really unlock the converter on the highway... don't really need to.
Since we have been hearing about how my transmission caused electrical problems with your car on other boards. Lets deal with it here where you're not adding to someone who is paying for protection from a site.
I will not edit this thread whatsover, but if a post is made throwing flames (in any direction)I will delete it, I want to the root not a bunch of flame throwers.
Lets here from the other 3 people with my transmission who have an excessive timing spike to result as well....
Alan
 

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Discussion Starter #3
Want me to just start a new thread incase it needs to be deleted?

I'm not going to alienate the other 3. If they want to speak of their problem, then so be it.

Here's what I know--

I've got a 450hp J-mod, Mechanical diode, and upgraded clutchpacks (and some other minor things) in my transmission; as well as a 9.5" 3800 stall single plate converter that I am very fond of.

After the transmission's install, there became a delay after the 1-2 and 2-3 shift. It lasts about .5 secconds, and feels the same as hitting the 3000rpm limiter in 4th. On a datalog, it shows "1.07 million" degrees of timing, which is obviously a false reading.

So, During this delay, where the timing jumps (in some direction), the torque converter only stalls at 3700, and the car really doesn't accelerate. Obviously, the motor isn't making as much torque as before.

A tune DOES fix this completely; however, in both of my friend's cars that have been J-modded according to the tech articles, the problem isn't there to start with.

I don't know if anything is really electrically "Wrong" or just not what the computer is used to seeing. That kindof steps into the "proprietary modifications" relm I think. Maybee some of the sensors in the transmissions are sending a revised signal to the computer? This is where I'm not completely clear on what's going on.

So the problem is that the stock computer freaks out, and throws a red flag right after the shift. What I don't understand is why this happens with a fully built transmission and torque converter, and not a car with a marauder converter, and the valvebody mods in Jerry's article.

Thanks for taking the time to consider what's up with this thing.
 

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As I told you from the beginning that is the effect of stall on these engines and a tune can fix the parameters. It has nothing to do with the transmission at all.
The stall only going to 3700 means you're actually getting more than 3800 stall. If you put a brake on it I bet you'll go closer to 4000. When we first discussed it you asked me if a tune was required and I told you "no it isn't required but you may have some quirks until you get it done" This is all well and true. You then asked if it would hurt it and I told you "no" but it will not give you optimal performance. It's now been a good bit of time and the transmission still works as it always did, however it is now a problem on my behalf as to why the symptoms that I told you would exist now exist. I don't understand. Especially to the point it went to.
I was straight forward with you and more than fair. Anyone with that much stall on one of these cars will have the exact same symptoms. Plain and simple. My car did it before I had it tuned. That was before I ever touched the transmission either.
Alan
 

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Discussion Starter #5
So you're saying its the converter that is causing the ECU to pull timing?

What did your symptoms feel/look like on your car? I want to make sure we're talking about the same thing since it happens in such a short period of time.

I'm having some trouble seeing what triggers the factory ECU to pull the timing on this.
 

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I can't speak much of the tuning parameters and what is electronically going on. I do however know for a fact that all these cars do it with that much stall. I also know there aren't 3 people with my transmissions having these exact same symptoms, 3 people with my converter is more than likely it's probable. At wot there are no symptoms. At low to mid throttle there is a delay between shifts. This delay is the converter not being fully charged due to the rpm drop. It almost feels like the transmission falls out of gear for a second. I'm sure the stock pcm is confused by not seeing the rpm drop it expected and doesn't understand the load. leaving that timing spike. You actually pointed out the timing spike to me I always just related it to the converter. I don't know how else to help you on this. I told you going in a tune would be needed eventually. All I can do at this point is seperate products on my web site so I can add the note.
"transmission and engine tuning could be required". I have actually seen the problem (not as severe) on a 95 car with a stock marauder converter. so it doesn't take much stall over stock to confuse the pcm.
Alan
 

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I am not 100% sure of what is being seen here with this situation yet and I am not here to start a war.

I think what Alan is saying about the computer getting info on load and what it is doing to the spark is likely. I don't know why it's happening though. If I had a datalog and the tune file I could probably pinpoint it. What I have heard and seen on this with the very limited info that I have, this looks exactly like something that I addressed on my own stuff a couple of years back. Something that people had a really hard time addressing in the tune. In regards to that, and to prevent any further finger pointing, there is still an issue on some cars on a very harsh downshift that is completely related to the tuning and if that comes up please don't blame the transmission or torque converter builder. That problem is totally vehicle specific and computer related. I have heard that the fix has been found in the tune, but I haven't gotten word on what it takes to straighten it out.

What I do know is that there were some things that I have learned over time that you can do internally in the transmission and particularly in the valve body that will almost eliminate these sorts of problems. I have also used some very high stall converters in cars and not had this problem show up without other changes having been made on the setup.

Again, I am not out to start any trouble, I don't know what is going on here for certain and I may be completely off base. I never actually heard anyone say that anything caused an electrical problem though. I did hear that there was an issue that was causing the timing to go whack on at least 1 car. I also heard that this was an issue on more than 1 vehicle, but I have no details on the others. I also saw some videos that didn't really show much out of the ordinary in and of themselves.

The delay on the shift is only correctable through internal modifications in the transmission and the valve body and really won't hurt too much by itself. You just end up with a little extra slippage on the part throttle shifts. Not enough to cause any sort of problem and definitely not worth pulling the transmission out over.

The timing issue is something that needs to be straightened out though and that most likely may be addressable through the tune. It will require datalogging the parameters that the computer is watching to see why it is messing with the timing. You will need a tuner that is very knowledgeable in the transmission portion and it may take the highest level of SCT dealer software to get to the parameters that need to be adjusted. But that all depends on what is causing it to happen of course.

This isn't a simple do this and get that issue. The fix wont' be that easy either. It will involve participation of all parties and them working together to get it resolved.

Darrin
 

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The timing issue is something that needs to be straightened out though and that most likely may be addressable through the tune. It will require datalogging the parameters that the computer is watching to see why it is messing with the timing. You will need a tuner that is very knowledgeable in the transmission portion and it may take the highest level of SCT dealer software to get to the parameters that need to be adjusted. But that all depends on what is causing it to happen of course.

This isn't a simple do this and get that issue. The fix wont' be that easy either. It will involve participation of all parties and them working together to get it resolved.

Darrin
and that is why tuners don't guarantee mail order tunes, and for the finer points, you need a dyno session so you have the time to datalog etc

btw, i moved these posts into a new thread in the main DT forum rather than clog the other thread up about TC & gears
 

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Feel free to elaborate all you can, better yet just teardown a few valvebodies and show the difference.
I was going to , but it would be alot easier on me if you did.
Alan
 

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Oh, I see what happened. I was looking in the other post :D

At wot there are no symptoms. At low to mid throttle there is a delay between shifts. This delay is the converter not being fully charged due to the rpm drop. It almost feels like the transmission falls out of gear for a second. I'm sure the stock pcm is confused by not seeing the rpm drop it expected and doesn't understand the load.
Strange... I'm not seeing any issues under what feels to my foot like 75% throttle.

The only thing causing the delay happens after a WOT shift completes. The tires already chirp, then the computer pulls timing.

There doesn't seem to be any drastic change in the calculated load, EPC, TC Speed Ratio, TCC absolute slip, or anything that I logged. I may be logging the wrong things though. Darrin, do you know of any place I can go to read what variables the stock tune uses to calculate spark advance?

Lonnie sent me a tune with the transmission parameters that he was going to put in my new motor's setup, and it worked fine, so bravo to him on that one. I feel its important, though, to know why certain vehicles have this timing spike, and others don't. Its the whole "What could this do down the road" thing that jumps out at me. This is especially scary on a blown car running pump gas... I don't KNOW that this issue can cause the timing to spike down the road, and cause detonation, but what if it does.....
 

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This is especially scary on a blown car running pump gas... I don't KNOW that this issue can cause the timing to spike down the road, and cause detonation, but what if it does.....
As I told you before when you PM'd me about this, tuning will take care of this issue. I have had no troubles whatsoever with the trans and TC that Alan built for my car, but I've also done the necessary work using a XCal 2 with the PRP to make sure everything is perfect.

I don't want to get into the middle of all of this, but it just seems like you're making a huge deal out of something that everyone has told you the answer to (get a tune). Don't take that as a flame or anything.

-Rod
 

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Discussion Starter #12
Rod, I already have a tune, and the timing spike doesn't show up.

The timing spike should not have been there to start with though. Yes, like I've said before, it can be fixed with tuning. But think about it -- Thats really not fixing anything. Its covering it up.

What I'm saying is that we don't know what we're dealing with yet. The best explanation I've gotten was that the computer is freeking out because it sees the tach at 700rpms higher than its used to after the shift. This does not explain at all why the symptom only occurs at WOT. Plenty of times with the stock tune, I put out enough torque to sit at 3.5k rpms, well above the actual speed of the gear, and shift without any issues.

Yes, I am making a big deal about this. I believe in doing things the right way. If I don't understand what is happengin with my car, I investigate the issue, and talk to people until I find out whats wrong. I don't just change some parameters to hide the issue.
 

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I guess I just don't understand why you would expect the stock tune to run a heavily modified transmission and TC perfectly. If you swapped in a set of 4.10 or 4.30 gears, you would need a tune. If you swapped in a set of cams, changed the MAF, increased the engine displacement....you would need a tune. Why should the transmission/TC be any different? The "problem" is in the stock tune on the EEC, which is proven by its sudden disappearance when you had the car tuned. The stock tune is designed to control a stock transmission/TC, you need a modified tune to control a modified transmission/TC. That's just part of life with a newer computer controlled car.

-Rod
 

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Discussion Starter #14
Actually Rod, you might be able to share some insight with us that don't have the Pro Racer Package...

What all did you have to change for your car to accept the new transmission and torque converter you put in your cougar?
 

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Discussion Starter #16
From 4500 in first to 3700 in 2nd.

(3800 stall minus the torque decrease from timing "spike")
 

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Actually Rod, you might be able to share some insight with us that don't have the Pro Racer Package...

What all did you have to change for your car to accept the new transmission and torque converter you put in your cougar?
I'd have to go back and look through the tune files, but from what I remember, it was mainly just setting up the commanded shift and TC lock/unlock points.

-Rod
 

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Discussion Starter #18
So... Nothing to tell the car to expect rpms to drop to 3500 (your stall speed) rather than 3000ish? And nothing to tell it that it's shifts now only take 200-300rpms?
 

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You've got a few assumptions incorrect there. My shift points are much higher than yours. My 1-2 shift happens at 6800 rpm, which drops it to 4500 rpm in second. The 2-3 shift happens at 6300 rpm, dropping it to 4300 in third. My stall rpm is around 3000-3200.

And nothing to tell it that it's shifts now only take 200-300rpms?
If you're referring to the time from the commanded shift and the actual shift, yes, I did have to take that into consideration back when I was running the transmission that I built. Those values didn't change with the new transmission, as we used my valvebody when assembling this transmission.

The main changes that would need to be made in your tune would be in the shift schedule and TC lockup schedule. There are also values that could be changed for clutch fill times for each shift, gear timing, etc.

-Rod
 

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Discussion Starter #20
You've got a few assumptions incorrect there. My shift points are much higher than yours. My 1-2 shift happens at 6800 rpm, which drops it to 4500 rpm in second. The 2-3 shift happens at 6300 rpm, dropping it to 4300 in third. My stall rpm is around 3000-3200.
Ah, I was under a misconception that you were running more stall than that. My bad.

Assuming the theory of the 700rpm drop I'm seeing is correct, you wouldn't ever see the same issue, even if you had it. Really, we'll probably have to hear from someone who has a tuned high stall car that does not rev higher than stock.

EDIT: Actually, they might never see that even. It probably happened because I was shfting at 4500 due to the J-mod.

If you're referring to the time from the commanded shift and the actual shift, yes, I did have to take that into consideration back when I was running the transmission that I built. Those values didn't change with the new transmission, as we used my valvebody when assembling this transmission.

The main changes that would need to be made in your tune would be in the shift schedule and TC lockup schedule. There are also values that could be changed for clutch fill times for each shift, gear timing, etc.

-Rod
Hmm, so if I'm reading this correctly, the computer doens't actually *Know* its shifting faster... Its just told to wait later to actually do the shift so that everything happens at the right times. Does that sound correct?
 
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