Share |
Go
New
Find
Notify
Tools
Reply
  
Grid question
 Login/Join
 
DRR Pro
Picture of 27Keith
posted
I will try to keep this short and to the point. I have had this car about 3 months now, Grid, Racepak, all the bells and whistles. Trying to learn all this stuff at once. This past weekend with the air getting good and et's dropping, I noticed this on my Racepak graph. The shift is set at 7400 on the grid, turn on at 7400 off at 7700. It is also set with the output switch not the shift light. Well, I was looking at my voltage and as expected when the electric shifter activates at 7400 it shows on the voltage. What is happening in high gear at 7400 (better air ,more rpm) my voltage is showing a drop again. It has to be the shifter trying to shift again. Is there a way I can keep this from happening in high gear ? Remember I am shifting off the output switch not the shift light. If I was to run 1/4 mile and get over 7700 would the shifter shut off and show on votalge guage ?


'12 Track & Top Class Champion
 
Posts: 2057 | Location: out there | Registered: March 31, 2004Reply With QuoteReport This Post
DRR Sportsman
posted Hide Post
In Grid, because you decided to use the Output Switch “RPM Switch” function to shift your transmission, you need to only allow the Output Switch event to happen in a time window controlled by the “Time Switch” settings in Output Switch. This will only allow the Output Switch to turn ON during this time period.

Do this. In the Data Acquisition of the run, zero the run to Launch. Open the Output Switch channel and determine the time value from launch that Output Switch turns ON to make the 1-2 shift.

Example.. If the Output Switch turns ON 1.75 seconds after launch subtract 0.50 from this and the 1.25 will be entered in the Activation Point setting of Output Switch. Set the Duration to 1.50. Enable the Time Switch along with RPM Switch. Here’s what you programmed. You created a “Time Window” of 1.50 seconds that starts 1.25 after launch. When the RPM Switch settings are achieved in this Time Window the Output Switch will turn ON. After the Time Window has expired the Output Switch will no longer turn ON when the RPM Switch setting are achieved at the end of the run.

Consider programming the RPM Switch in Hysteresis mode. Set RPM ON to 7400 and RPM OFF to 7200 . This keeps the Output Switch ON though the completed shift and turns OFF when below 7200 on fall back of engine rpm.

Whenever using Output Switch, whether for RPM or TIME activation, you may need to use the opposite function to create the “window” of when Output Switch will turn ON.

As I’ve written before, consider using the Shift Light function to shift your transmission. This has programmable settings to keep from shifting in the event of peddle and limits the shifts by the number of gears selected in the Settings / General tabs.
 
Posts: 644 | Location: 53056 | Registered: December 30, 2009Reply With QuoteReport This Post
DRR Trophy
posted Hide Post
kinda off topic, but if you use the shift light output to trigger the shifter, could you use the output switch (rpm disabled, time function enabled) to operate a throttle stop?
I don't see why it wouldn't work..
 
Posts: 61 | Location: South MS | Registered: September 07, 2015Reply With QuoteReport This Post
DRR Sportsman
posted Hide Post
^^^^^^^^^^^^^^ That is correct.

And if you need more Output Switches, install a MSD 7760 Power Grid Programmable 3 Stage Delay Timer to the 7740 CAN-bus hub and you’ll have 3 more outputs controlled by Grid.
 
Posts: 644 | Location: 53056 | Registered: December 30, 2009Reply With QuoteReport This Post
DRR Sportsman
Picture of 329L
posted Hide Post
If you want to shift at 7400, you need to have the "on" at 7400 and the "off" at like 7200. With what you are doing, its trying to keep power to the solenoid once it makes rpm.


Jeremiah Hall
 
Posts: 117 | Location: Evansville, IN | Registered: February 24, 2010Reply With QuoteReport This Post
DRR Pro
Picture of Lenny5160
posted Hide Post
quote:
Originally posted by 329L:
If you want to shift at 7400, you need to have the "on" at 7400 and the "off" at like 7200. With what you are doing, its trying to keep power to the solenoid once it makes rpm.


This is what I do also, with the OFF 200 below the ON.

The time window thing that Mark described would also be a benefit here.


Tony Leonard
 
Posts: 2322 | Location: Inver Grove Heights, MN | Registered: March 18, 2004Reply With QuoteReport This Post
DRR Pro
Picture of 27Keith
posted Hide Post
For everyone who has it set on at 7400 and off at 7200
What do you have your number of gears set to under settings and general tabs ? What keeps it from coming on everytime it sees 7400 ?


'12 Track & Top Class Champion
 
Posts: 2057 | Location: out there | Registered: March 31, 2004Reply With QuoteReport This Post
DRR Pro
Picture of Lenny5160
posted Hide Post
quote:
Originally posted by 27Keith:
For everyone who has it set on at 7400 and off at 7200
What do you have your number of gears set to under settings and general tabs ? What keeps it from coming on everytime it sees 7400 ?


I don't have anything else special configured. If it comes on again, and it very well may, I don't know about it.


Tony Leonard
 
Posts: 2322 | Location: Inver Grove Heights, MN | Registered: March 18, 2004Reply With QuoteReport This Post
DRR Sportsman
posted Hide Post
quote:
Originally posted by 27Keith:
For everyone who has it set on at 7400 and off at 7200
What do you have your number of gears set to under settings and general tabs ? What keeps it from coming on every time it sees 7400 ?


The Output Switch is “NOT” controlled by the number of gears you selected in the Settings / General tabs. The Gear setting is ONLY used by the Shift Light tab.

With 2 gears selected, go to Shift Light and you’ll see First Gear. Now go back and set the Gear to 4. Return to Shift Light and your see Gears 1 – 2- 3 for programming.

You need to use the Timer function in Output Switch when programmed for RPM like I wrote in my first reply. Output Switch will turn ON every time it sees 7400 like you have it programmed to without programming the Time Switch function.
 
Posts: 644 | Location: 53056 | Registered: December 30, 2009Reply With QuoteReport This Post
DRR Sportsman
Picture of 329L
posted Hide Post
I usually never make enough rpm after the gear change to turn it back on when I was shifting on RPM, but I almost never make 1/4 mile passes so never noticed in the date logger. I quit shifting on RPM a while back and started using the delay box to shift on time, in case I need to move it on the fly.


Jeremiah Hall
 
Posts: 117 | Location: Evansville, IN | Registered: February 24, 2010Reply With QuoteReport This Post



DRR Trophy
posted Hide Post
When using the output switch to shift, if you enable time and put values in there, both conditions will have to be met before it supplies the ground.

Therefore it will have to be at shift rpm and so far into the run before it fires. Once outside the time window it won't fire again on the top end even when the rpm is met.

https://www.dropbox.com/s/3hog...ut%20Switch.png?dl=0
 
Posts: 41 | Location: Ohio | Registered: October 06, 2015Reply With QuoteReport This Post
DRR Pro
Picture of BarneyB
posted Hide Post
Just change the shift by rpm to the shift light output. Simple to do, markekark knows these the best but every car I wire I use the shift light (yellow wire) to shift by rpm and the rpm/time switch (brown/white wire) to shift on time.


Blaster Chemical Co.
www.abruzziracing.com
www.moserengineering.com
www.houseofpayneperformance.com
WiredTwoWin race car wiring
J & J Performance
Trick Flow Specialties



 
Posts: 2406 | Location: Wadsworth, Ohio | Registered: December 12, 2001Reply With QuoteReport This Post
  Powered by Social Strata  
 


© DragRaceResults.com 2017