2 step activation.
 

Which one seems to work better to activate the 2 step, a button on the pedal, or a pressure switch?
First time out with the new car. I noticed a little hesitation right on the launch, almost like the 2 step was still activated. I currently have a button in the pedal. When I'm releasing the pedal in the garage I notice the button bounces.

Re: 2 step activation.
 

We have the pressure switch. Leaves very clean

Re: 2 step activation.
 

hi have mine on my brake light switch, a lot of travel very inconsistent, what are you using for a pressure switch?

Re: 2 step activation.
 

I tried the brake light switch setup with the nova. Was a little Leary of the 2 step being activated every time I hit the brakes. Here’s the link to the pressure switch I plumbed in. I know of a handful of racers that use it and have had good results. So far so good with me too. Be sure to get the specific wiring harness when ordering. https://www.automationdirect.com/adc...xoCwCEQAvD_BwE

Re: 2 step activation.
 

is the one wire switch on most oem (mopar) proprietary valves just a ground to turn dash light on??

Re: 2 step activation.
 

I've used United Electric Controls pressure switch model 10-B12 on quite a few cars ,
Very easy to adjust . shop them online ,not inexpensive ,usually cost around $160, but well worth it .

Re: 2 step activation.
 

Assuming you are using the 2-step for launch control, I think the 12V signal to activate the 2-step should come form the Line-Lock solenoid or the trans-brake solenoid.

If you want it activate from the brake pedal, I would use a 12mm cylindrical proximity switch to drive a relay and use the relay contact to activate the 2-step. Prox switch is easy to fab up a mounting bracket & adjust. Trip point is very repeatable.

Re: 2 step activation.
 

Thank you everyone for the help!

Re: 2 step activation.
 

The adjustable ones from Tansducers Direct work great. -Al

Re: 2 step activation.
 

Brother, you want to use a pressure switch go the additional mile to ensure the switch only sees ground in first gear. Also a big proponent of wiring different colored indicator LEDs to confirm switch has power (you didn’t stage in 2nd, not that any of us have ever done that, lol) and the second to indicate pressure switch has activated the two step. I am a fan of the IFM ELECTRONIC PK6522 PRESSURE MONITOR but there are other viable solutions.

Re: 2 step activation.
 

Thank you sir!

Re: 2 step activation.
 

Why use a pressure switch? Is it plumbed in the brake line?

Re: 2 step activation.
 

Folk race cars use to have the solenoid setup. 815 629 2418 Tom

Re: 2 step activation.
 

I bracket race so I don't have to follow the same rules as class racers. I've used a pressure switch for years footbraking and it works great. I'm also cheap so I use a basic 2 terminal pressure activated brake light switch from an early vehicle, looks the same as the generic one Jegs sells. I also have a small LED wired in to let me know it's activated, also helps you judge braking pressure. Because I don't have to follow stocker rules I have a shutoff switch in the circuit for down track. I used to have a toggle, now I have a button on the steering wheel so when my thumb is on the button the 2 step can be activated, after launch I slide my finger off and then I can ride the brake and no 2 step down track. I'm sure a different switch method can be devised but I have no clue of legality. You could use a pressure switch on the transmission or a micro switch on the shifter.
As for plumbing I have a Hurst linelock and I screw the switch into one of the 1/8" pipe threaded ports on it.

Re: 2 step activation.
 

How much brake pressure is to be expected in the braking system of the rear, high, low, average, I'm wanting to put a gauge along with a pressure switch, thanks

Steve

Re: 2 step activation.
 

I think it all depends on the brake system of the car. The nova has completely stock factory 4 wheel manual drums. I set the brake pressure switch to activate at 700lbs. I should NEVER see that kind of pressure hitting the brakes at the end of the track unless there is a panic situation, and even then that would be well into the lock up range. I've heard of racers running them lower and higher than that. The switch I use also allows for an adjustable setting for where you would want the 2 step to deactivate. Allows for some more fine tuning in your reaction time. I'd say set it up where you feel comfortable the car is going to hold as well as where you can naturally hold that pressure without having to worry about if your foot is down hard enough.

Re: 2 step activation.
 

Hey Doug, Thank you for the helpful info.
Where would a good spot be to set the reset point?

Re: 2 step activation.
 

The switch that I use suggests at least 50psi split between the activate and reset pressures. Right now I have them about 100psi apart. This is where the little bit of reaction adjustability can come into play.

Re: 2 step activation.
 

just remembered this from my dads 1962 buick when I was in high school (1973)
napa switch SL139 wire connector ARC120 $8.00 each