more 8973 wierd stuff

Grid

I would say you got your money's worth out of the 8973 and put it in the pasture. Can you afford for that thing to go skitzo and shitcan another motor? Hard to pin your crankshaft deal on it, but it has motive and doesn't have a real good alibi as they say in the TV shows.

In regard to programming, why use the step wire to fine tune the timing? Personally I like to have the trigger in the same 'right' spot every time. That way if I want to go back and grab an old timing file for a particular run, I don't have to compensate. To some degree I probably answered my question, just you are using the step to compensate. Given the opportunity to use a mechanical setting vs electronic, I would rather move the trigger to the point I want it rather than rely on the 8973 or Grid to get it where you want it.

Another nice thing about the Grid is the ReView will tell you what the box did during a run and you can usually diagnose why something is not happening.

The wiring is pretty damn close so it shouldn't be that hard to change to.

 

I agree with Will that the Power Grid is a step beyond the 8973 but there is still nothing wrong with the 8973. We have a Grid on both cars and they work well and I had a 8973 on two cars and they worked well. I don't think it is time to throw the 8973 out yet. 90% of the problems with the 8973 and the grid are external to the unit and either a wiring problem or an operator problem. Lets go over what you are seeing.1. Nothing wrong with using a Step retard to adjust the timing. To the box it is no different than applying a retard curve when it is going down the track. It is a very simple and accurate way to adjust timing without having to move the trigger. 2. As far as the Step retard turning on and off with the transbrake sounds like a loose 12v or ground connection causing the 12 volts to the Step retard to drop. Hook up your laptop and watch the MONITOR in the upper left quadrant of the screen and turn on the system. It should show that the Step retard is turned on right away. Now press the transbrake button off and on several times and watch the MONITOR on the screen and see what happens. The Step Retard should stay on the whole time. The next thing you can do is leave it all turned on with somebody watching the screen and move all the wires and see if it turns on or off. Let me know what you see and we can go from there.3. The RPM based Timing Retard problem. You need to tell me more. Are you using the Upper Right graph that say Launch Retard Curve or the Lower Right Graph that says Run Retard Curve or what are you using?

 

agree with Will that the Power Grid is a step beyond the 8973 but there is still nothing wrong with the 8973. We have a Grid on both cars and they work well and I had a 8973 on two cars and they worked well. I don't think it is time to throw the 8973 out yet. 90% of thIe problems with the 8973 and the grid are external to the unit and either a wiring problem or an operator problem. Lets go over I you are seeing.1. Nothing wrong with using a Step retard to adjust the timing. To the box it is no different than applying a retard curve when it is going down the track. It is a very simple and accurate way to adjust timing without having to move the trigger. 2. As far as the Step retard turning on and off with the transbrake sounds like a loose 12v or ground connection causing the 12 volts to the Step retard to drop. Hook up your laptop and watch the MONITOR in the upper left quadrant of the screen and turn on the system. It should show that the Step retard is turned on right away. Now press the transbrake button off and on several times and watch the MONITOR on the screen and see what happens. The Step Retard should stay on the whole time. The next thing you can do is leave it all turned on with somebody watching the screen and move all the wires and see if it turns on or off. Let me know what you see and we can go from there.3. The RPM based Timing Retard problem. You need to tell me more. Are you using the Upper Right graph that say Launch Retard Curve or the Lower Right Graph that says Run Retard Curve or what are you using?

 

So what would you use for timing control on a ProXtreme car with a screw blower and converter that runs the eighth mile in anywhere from 3.48 to 3.84 seconds and needs to pull out massive amounts of timing on launch and bring it back in smoothly going down track.

 

When you start the motor it automatically is in the Run Retard Curve which is the bottom graph on the lapto screen. The way the 8973 and the Digital 7 and the Power Grid is that the BLUE into all the units requires a 12 volt signal when the clutch pedal is pushed of the transbrake button is pushed to switch it into the "ready to Race" mode. So the 12 volts activates the two step, resets the shift lights to be in the first gear, and moves you from the Run Retard curve to the Launch Retard Curve. The Launch Retard Curve could also be called the First a Gear Retard Curve and the Run Retard Curve could be called the
2nd and 3rd gear curves. So the first thing I ask is do you have 12 volts going to the 8973 BLUE wire when on the transbrake or have the clutch pedal in and does this 12 volts go to 0 volts when the clutch pedal is released or the transbrake button is released? Does your two step from the 8973 work normally! Can you see on the laptop screen in the upper left area under Monitors that if you turn on power to the 8973 it comes up in the Run Retard Curve and do you see it switch to the Launch Retard curve when you push the TB button or clutch in?