PDA

View Full Version : timing with 7531


1fastmustang
10-22-2006, 08:14 AM
Is it possible to set your crank trigger at maximum timing and control your base timing with the 7531? Example: 36 degrees at the crank trigger but because weather conditions are so good I only want to run 34 degrees all the way down the track.

Is this done through the individual cylinder timing, or is there other ways to accomplish this?

Thanks

Eric David Bru
10-22-2006, 10:30 AM
While possible, it would be more effective to use the launch retard and gear retards to accomplish this.

There will be points during each gear where you can utilize all of your power, even on marginal tracks. So you can use the launch retards to pull timing at the start and gear retards to soften the power on the gear changes. Ramp the timing in and out.

I would not use the ICT to accomplish your goals.

Eric David Bru
10-22-2006, 10:32 AM
You could also use your slew rate RPM limiter to accomplish your goals.

Be careful if you are using N2O however.

1fastmustang
10-22-2006, 11:00 AM
Looks like I have some homework to do. How would I create a timing curve on the gear retard to pull 2 degrees out all the way down? I assume that I would set the points on the graph at a lower RPM than the engine will ever see then copy the curves in all gears.

Eric David Bru
10-22-2006, 04:14 PM
If you want to pull 2 degrees out and leave them out for the day just change it at the crank trigger.

1fastmustang
10-22-2006, 06:15 PM
I was trying to avoid changing the timing at the crank trigger. I wanted to have the option of putting timing in at the gear change or possibly early in the run. Just seems easier to change timing with my laptop then with my 1/2" wrench....

Thanks

Eric David Bru
10-22-2006, 10:26 PM
Take the timing out with the 7531 and ramp it back in.

You shouldn't need to take it out and leave it out for the entire RPM band.

msdtech4
10-23-2006, 09:29 AM
1fastmustang,

If you want to retard the timing you can either program it in to the gear retards or you can activate a step retard. This way you can leave the crank trigger at 36 and retard the timing as you need from that point with out touching the crank trigger. You could ramp this in or out as needed or just leave it it out.

Thanks,

MSDtech4

1fastmustang
10-24-2006, 06:57 PM
Would I acheive this on the gear retard graph by starting my RPM curve at a RPM lower than the engine would operate? Example: The car leaves at 5000 rpms and that is the lowest rpm through the pass. Would I start the curve at 3000 and copy it for all gears?

Thanks

msdtech4
10-25-2006, 09:11 AM
1fastmustang,

Yes that would work fine. This way idling around etc. you are at full timing and when you launch the car it is retarded back to the value you want. If the track if really good you could zero out the curve so the timing is back to normal. This way you get the best of booth worlds.

Thanks,

MSD tech4