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2 step?

Guest rt1092

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Guest rt1092

Hi. I'm running an automatic trans drag race car. I set my launch control launch rpm 3100, trim activation 50% tp, ignition trim activation 2500, Advanced mode is off.

It holds the car at 2900 rpm but varies to a low of 2000. I'm trying to tighten up the launch rpm. To hold it within a 100 rpm range.

Can I do this? What settings control that

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Why do you need ignition retard ? is this to build boost.

I would make the ignition trim activation 90% TPS.

If the engine is turbocharged, avoid using ignition cut as it can damage the turbocharger and the engines valve train. Fuel cut cannot hurt anything and should always be used with turbochargers.

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Guest rt1092

I need the 2 step to when I stage the car (drag racing). I put the car in the staging beams, then step on the brakes hard to stop the car from rolling forward. Then press the 2 step activation button, then floor the gas pedal. When the starting lights go on I release the button and lift off the brake.

I need to have the engine hold at a certain rpm with full throttle. To get a consistant reaction time and repeatability on the car leaving the starting line.

The car is front wheel drive, has a torque converter driven automatic transmission, and is naturally aspirated 2.4 ltrs with 15 to 1 compression. Individual throttle bodies. Weighing 2600 pounds.

I have a problem with a motor not holding at a specified rpm (within 100 rpms). It hold fine in neutral, but when I bring up the rpms in gear against the brakes. It gets very eractic.

I have richened the fuel mixture up quite a bit at the rpms the 2 step comes on, and helped it a bit. Before that when I let go of the 2 step button the motor still popped and banged (lean condition?). For a couple of seconds until the motor cleaned out and ran normal.

When I run at the track I don't use a muffler, but in my garage I usually put one on the car. I noticed the motor reacted better to the 2 step with a muffler. That is why I richened it up. And it seemed to respond well.

The reason I set the throttle position activation at 50% was I was worried the car would overpower the brakes before I got the throttle open.


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