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Discussion Starter #1
I have been having a couple of issues lately and I am trying to get them sorted out. I am not sure if they are electrical (wiring or tuning) or mechanical issues.

I have a Jake's Stage 5 4L80 with a D3 transbrake. From his website, this includes a billet input shaft, billet rollerized forward hub, billet intermediate shaft, and 36 element sprag Super Drum and his D3 brake. I have had this a couple of years and I am guessing I have 2500 miles on it.

This is in a heavy F-body (3900lb raceweight), 3.25 rear gear, and MT Pro Radial Tire (28.2" tall). The transmission is electronically controlled through Holley Dominator.

I am looking to solve 2 issues.

The first, the car does not want to make a 1-2 shift at WOT. It goes right past the commanded shift point, hits the rev limiter, and eventually shifts from 1st to 3rd.

I have tried adjusting the WOT shift RPM and also have tried different Shift Tables. It didn't seem to help. It is difficult to test on the street because of the power on the 1-2. Currently, the car is down, but looking to see whether people think there is something mechanically in the transmission, or electrically in the tune.



The image above is from my latest track outing. The WOT shift was set at 6500 on the 1-2 shift. I eventually pedaled the car and then got back into it in 3rd gear. I have a transducer on the 4L80 and this is labeled "4L80 Pressure". The thing that stands out to me is how the pressure is falling off around 5800 RPMs.



The image above shows the burnout from the pass above. This shows the transmission shifting as it should at part throttle.



The image above is a screen shot from the Transmission Setup in Holley from the pass above.



The image above is a screen shot of the Shift Parameters from the pass above.

I have also tried lowering the 1-2 WOT RPM to 5800.

This is a screenshot of that pass:


I added the transducer between the passes. The pass at the top was recently in August versus this one directly above that was in July.

Looking to see where we can go with this. I can try to post the Data Logs if needed.


Problem #2:

When I engage the transbrake, the car rolls forward before actually engaging. To offset this temporarily, I engage the TB, hold the brake pedal and start to apply throttle. From there I release the brake and it holds to fully apply throttle.

I have found this thread with a similar situation: http://www.yellowbullet.com/forum/showthread.php?t=1028994

I wired a relay to cut power to the EPC as discussed in that thread. However, I wasn't seeing the results.

The latest pass shows the 4L80 pressure for this:

The pressure actually goes down slightly when the Transbrake is engaged. Then as I bring in throttle, it jumps.

Any ideas on either? Could they be related?

Also going to post in the Electrical Section.

Any help is much appreciated.
 

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How does the fluid level look?

Have you checked the accuracy of the dipstick?

Call the shop and I'll tell you how to fix the transbrake setup time delay issue. That's easily solvable. The shift issue is too most likely but may be too late.
 

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I just went through the exact same thing. Ended up machining a spacer to drop the filter to the bottom of the pan, fabricating a baffle right behind the filter to control slosh, and running 17 quarts of fluid in it. If it has a lokar dipstick in it, don't go by that , it's was way off for me. Had to go an inch up on the cable to get it close.
After getting line pressure to be a steady 20psi across the entire run, the clutches were burnt after all the passes with it low so it will need a rebuild for sure.
 

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Discussion Starter #6
What is your first gear ratio?
2.48

How does the fluid level look?

Have you checked the accuracy of the dipstick?

Call the shop and I'll tell you how to fix the transbrake setup time delay issue. That's easily solvable. The shift issue is too most likely but may be too late.
Fluid level is perfect. Checked frequently and also just before some of the passes.

Dipstick is accurate. I have had the pan off too many times to count this year. That was one of the first things we have checked. I was the same guy that had the early troubles with Holley and ended up having the bad pressure sensor.

I will give you a call later today. Much appreciated Jake. I was going to contact you directly right away but thought I would put the post up here as well.
 

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Discussion Starter #7
Talked to Jake with Jake's Performance on the phone and gave me a few things to try.

Will be a little bit but will post up with feedback.

Thanks again Jake. Top notch customer service again for me!
 

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Only ERO's;3****170 said:
Talked to Jake with Jake's Performance on the phone and gave me a few things to try.

Will be a little bit but will post up with feedback.

Thanks again Jake. Top notch customer service again for me!
Did you ever figure this out? Mine did the exact same thing awhile back, I also have a Holley Dominator. My trans guy went through it and every forward clutch was slipped. It hasn't done it since I've gotten it back in, but I would like to know what caused it.
 

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Discussion Starter #10
Did you ever figure this out? Mine did the exact same thing awhile back, I also have a Holley Dominator. My trans guy went through it and every forward clutch was slipped. It hasn't done it since I've gotten it back in, but I would like to know what caused it.
I believe it was the intermediate clutches. I pulled the transmission and had it gone through. Some of the clutches were in bad shape.
 

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I had this issue and it was a sensor unique to what jake uses. Was a $6 fix. Wouldn't shift out of 1st at all.
 

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Ive seen this happen a couple of times.
We see more tuning errors that cause a no shift at WOT condition. Typically if the transmission makes a shift at say 80% power, it will make it at 100 unless there's a problem in the tune.

I'm curious though, can I get a customer name from all who have verified this. I want to see if they were all purchased at about the same time.
Also, is the switch damaged, possibly contaminated, and what do they read on a continuity test?

The only one I've seen go bad had a very slight continuity to ground when it should have had none. It was causing a fault with a controller.
 

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Discussion Starter #17
Ive seen this happen a couple of times.
We see more tuning errors that cause a no shift at WOT condition. Typically if the transmission makes a shift at say 80% power, it will make it at 100 unless there's a problem in the tune.

I'm curious though, can I get a customer name from all who have verified this. I want to see if they were all purchased at about the same time.
Also, is the switch damaged, possibly contaminated, and what do they read on a continuity test?

The only one I've seen go bad had a very slight continuity to ground when it should have had none. It was causing a fault with a controller.
Jake, my name is Josh Shones. Mine was ordered on 1/31/13.

There didn't seem to be anything visually wrong with the switch. I will have to look but I believe I pitched mine after the new one worked. If not, I will test it.
 

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I'm curious if it's possibly a bad batch of those switches.
The one I've personally seen in the shop caused the controller to just fault out. I remember speaking to you and one other guy about this previously too.
It seems like these are all from a couple of years ago as far as ship date.
I'll look at the other customer's original build date too.
 
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