I am using a GRID with a 7AL-3. With this combination the burn-out rev limiter feature in the 7AL-3 became disabled.

What is the process in using the GRID to re-enable the burn-out feature?

Thanks for any assistance.

Bob

Are you using the older 7230 7al3 (red in color) or are you using the newer 7330 7al3 ( black in color)?

Bob I use a grid controller with a red 7AL3
I never hooked up any of the grid rev control trigger wires and use chips in the 7AL3
It has always worked for me and I’ve had the grid in there for at least 5 years.
The info said the rev limiters may be harsh if I ran it thru the grid control so I didn’t.
I have used the grid to manipulate timing and record runs.
Nothing else..
Box went back to MSD once for firmware update.

The legacy RPM wires, two yellow wires with same connector as the chips, goes into the high side chip connection on the 7al. The grid then will internally change which rpm limit is active. The 7al will just act as if you changed chips in the high side connection.

quote:

Originally posted by RPROGAS:
I am using a GRID with a 7AL-3. With this combination the burn-out rev limiter feature in the 7AL-3 became disabled.

What is the process in using the GRID to re-enable the burn-out feature?

Thanks for any assistance.

Bob

Bob how is it currently wired ? All revlimiters thru grid or thru 7al3?

Like mentioned above you can get a very harsh rev limit using the 7al3/grid controller. I’ve seen this many many times and only sure the controller to run the timing map.

Why is the rev limit so hard with the grid/7al3? The grid is just changing the value of the chip to the 7al3, i would have thought the rev limit would be the same. I have seen grids on 6al's with no issues, so is it just a 7al issue? Asking because i have never added a grid to a 7al, always just went from 7 to full grid. Only have added grid to a 6.

It’s specifically the 7al3 only, years ago msd tech told me there was internal parts that were not compatible thru the legacy. It works fine with the old 7al and any of the 7al2.

Mark, I have the older (red) 7AL-3 unit. The original instructions sheet/diagrams did not include information on how to wire the GRID with a 7AL-3 (red) box. I contacted MSD Tech and they sent me a sheet of instructions. When I asked them about the burnout feature I was told that installing a chip in the 7AL-3 would not work, they didn't show me how to control the RPM during the burnout through the GRID.

Is there a way to used the GRID to set a burnout limit? I've primarily been using the GRID to establish launch timing maps and data logging.

The objective of using the data logging is to confirm that the down power (while on the TS) remains consistent.

The GRID is a great piece of equipment, I just would like to be able to set an exact RPM during the burnout process while the roll-control button is depressed.

Bob

Rich, I connected the 7AL-3 to the GRID through the legacy connection thinking the burnout chip would work....in my case it didn't.

I know that I am missing something here, but if the rev limiter combination of the GRID and the 7AL-3 can damage anything I can simply continue using my right foot to control the RPM.

Bob

Assuming you have burnout button hooked up (light blue on grid) where the rev limiter screen on grid is,it says burnout. If not working, verify the burnout input is working by going to the right side of the view software and clicking the gauge tab, go down to the button of screen and click the rev limit source box. This will show you which revlimit is active, push the burnout button it’ll show if it’s active.

Bob I do recall the wiring instructions included hooking a grid controller to most common older boxes including the 7AL3

I also am positive about the warning about harsh rev limiter using the grid with the 7AL3

I hooked it all up as per their instructions and its always worked for me.

Probably bought it in 2013 and have never touched it since sending back for update.

I don't even use the newer versions of the software and had issues early on with it...

I used to use it to add a timing launch retard when I ran injection. Thought it might keep the car from slipping the tires a little late during a race day when the track starts getting sloppy....

I also used it to retard timing for easier starting with injection. Tied my fuel pump switch to the grid as I had a Primer Plus and an electric fuel pump....

I record runs with it but to be honest don't use it much anymore...and have a replay tach that's easier to see

I usually look at runs after a race and then delete them all....

Chips in the 7AL3 for burnout, launch and high side....taped in so they stay in there...

A lot of wires from the grid are not connected to anything....

I am not sure why yours would not work just like mine does and has since day one....

Bob,

As was said by others, because you have the older 7230 model 7AL3, you do Not want to use the Legacy cable from Grid. You need to use the chips for all the rpm limiters in 7AL3.

You need to terminate the Launch and Burnout wires from Grid to 7AL3 and then program the Launch /BO RPM Limits in Grid for a higher value than the chips in 7AL3. 7AL3 chips are controlling all the RPM Limits , NOT Grid.

I can send you a wiring diagram and suggestions on how to best program Grid if you’d like this week.

Thanks for the help Mark, I understand your instructions.

Regards:

Bob