Question on tuning shift point for track only use
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From: Winchester, VA
Question on tuning shift point for track only use Is there any way to trick the computer into ignoring the shift mph at WOT? I'd rather remove as many variables as possible and dial in the rpm only if possible. This would be a 1/4 mile only tune and I'd run a seperate tune for the street. I'm using hp tuners software. Thanks
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From: Ann Arbor, MI
While I typically shift at 7000 RPM, I set my WOT Shift-MPH to correspond to about 6000 RPM. I also blend that value into the Partial throttle table.
Then at the track, I only need to change the WOT Shift-RPM to experiment.
Then at the track, I only need to change the WOT Shift-RPM to experiment.
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How are you determining your shift mph at 6000? Are you calculating or going by trial and error? That sounds like what I need to do. I took the car to the track and it would bounce the limiter on the 1-2 and 2-3. I pulled some mph out on the 1-2 and got it to hit my target rpm but no matter how much mph I pulled out on the 2-3 it would still bounce. The car was extremely consistent and would hit the limiter 3 times then shift, so I'm pretty confident that it's not a mechanical issue.
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From: Turnin' Wrenches Infractions: 005
How are you determining your shift mph at 6000? Are you calculating or going by trial and error? That sounds like what I need to do. I took the car to the track and it would bounce the limiter on the 1-2 and 2-3. I pulled some mph out on the 1-2 and got it to hit my target rpm but no matter how much mph I pulled out on the 2-3 it would still bounce. The car was extremely consistent and would hit the limiter 3 times then shift, so I'm pretty confident that it's not a mechanical issue.
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From: Winchester, VA
Right now I'm not tagged and inspected. It's down the list of priorities. I need a good test and tune day to screw with it.
I clicked that link nocooler but it says it's not available. Might be because I'm on
Mobile internet. I'll try it on the laptop thanks
I clicked that link nocooler but it says it's not available. Might be because I'm on
Mobile internet. I'll try it on the laptop thanks
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Check out the Apex Garage gear calculator online. Just plug in the trans and rear gear ratio, tire size, rpm's and it calcs the speed for you in each gear. It is real close. If your rear tire is 28", use something around 27.4" to be more accurate. Hope this helps.
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So I made it back to the track today. I used each of the suggestions you guys have posted and no change. So I'm convinced it's mechanical or there's something hiding in the tune. I'm at the point I'm going to swap a TH400 with a manual valvebody.
It went 11.500 @116 with a 1.52 sixty foot. DA was 2381 and track temps were above 130 at the starting line. It just would not hit third gear like it should. As best as I can tell all parameters were met. I thinks it's just time to go simple. I'm just at a loss. Last time out it stayed consistent this time it ranged from the 11.50 to 11.91
It went 11.500 @116 with a 1.52 sixty foot. DA was 2381 and track temps were above 130 at the starting line. It just would not hit third gear like it should. As best as I can tell all parameters were met. I thinks it's just time to go simple. I'm just at a loss. Last time out it stayed consistent this time it ranged from the 11.50 to 11.91
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From: Turnin' Wrenches Infractions: 005
You need to log commanded shift, plain and simple. To see if the shift is being commanded. If it is then its the trans, if it isnt then its something in the car.
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From: Winchester, VA
I did log my runs I just didn't think to set it up to log commanded shift. I looked them over and compared the mph and rpm to the tune. All those parameters were met so it should have commanded the shift. I even had the 2-3 set at 6500 hoping to hit 6800 with a 7200 limiter. I was thinking it could be that the fluid pressure wasn't correct for it to actually shift. I have the understanding that it can be commanded to shift whenever but if you don't have enough pressure it just can't shift.
I'm just on the fence. It could be something as simple as I screwed up putting in the shift kit, or the solenoid isn't functioning properly. But I checked the fluid to see if it looked or smelled burnt and the best comparison I can make to what I saw is like checking the oil and finding bearing material on the stick, only it was black. I wiped it off with a rag and could clearly see a line of black dust and fresh fluid.
I'm just on the fence. It could be something as simple as I screwed up putting in the shift kit, or the solenoid isn't functioning properly. But I checked the fluid to see if it looked or smelled burnt and the best comparison I can make to what I saw is like checking the oil and finding bearing material on the stick, only it was black. I wiped it off with a rag and could clearly see a line of black dust and fresh fluid.
Last edited by 1320Chicken; Aug 17, 2015 at 09:13 PM.
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From: Winchester, VA
That's what she's going to get. I'm looking at an FTI level 4. Comes with a RMVB and trans brake. A bit overkill for now but when the time comes to freshen up or rebuild the motor I shouldn't have any problems.