CLASS RACER FORUM - Brake pressure switch

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Re: Brake pressure switch

Quote:

Originally Posted by The Texas Rangers (Post 328936)

ATTENTION CLASS...The brake pressure switch is used with the REAR brakes, not the fronts. just sayin...The Texas Rangers.

OK, I just have to ask:
Since the car is going to move the instant the pressure falls below the switch pressure and the engine goes from it's chipped RPM to converter stall speed (regardless if the brakes are fully released or not and regardless of front to rear bias), WHAT difference does it make if the switch is in the front or rear hydraulics?

Re: Brake pressure switch

I use a switch from PDI PDAH-4-4M-C-FL-9. There are older versions of this switch that have a similar part number. There are a couple of these currently on ebay.

http://www.ebay.com/itm/PDI-PPDI-PDA...item35ac4b4a0d

http://www.ebay.com/itm/DYNAMIC-AIR-...item1c25be9020

You need a second switch in series on the shifter in first gear position so that the brake pressure will closed the micro switch when you step on the brake at the starting line and the switch on the shifter most be in first gear and closed also for the two step to be activated. This prevents the two step from activating at the finish line if you foot brake at the stripe. I use a common bump switch for the shifter mounted on a small bracket. I brake pressure gauge with a small light built into it is also a good option also. The pressure switch must be installed with the red wire (Normally open) and also the black wire = common. The pressure switch is adjustable, remove the screw from the top of the switch, using an 1/8 allen wrench to adjust clockwise to increase set point and counter-clockwise to decrease set point. Then replace the screw. Works by staging, stepping on the brake hard, stepping on the gas, releasing the brake to launch.

Re: Brake pressure switch

Quote:

Originally Posted by Dean Feiock (Post 328953)

OK, I just have to ask: WHAT difference does it make if the switch is in the front or rear hydraulics?

If you put it in the front brake line your starting line rev limiter will be activated when you have pressure held line lock on in the burnout.

We put the pressure switch that Brian and Nick Folk sell in our stocker a few weeks ago and tested with it Memorial day weekend. It is deadly consistent in the r/t department for our car and easy to adjust.

Re: Brake pressure switch

Quote:

Originally Posted by Brad Zaskowski (Post 329723)

If you put it in the front brake line your starting line rev limiter will be activated when you have pressure held line lock on in the burnout.

Not if you install it before the line lock.

Re: Brake pressure switch

Quote:

Originally Posted by Dean Feiock (Post 329747)

Not if you install it before the line lock.

Yes true.... Fronts brake line will work if before the line lock.

Re: Brake pressure switch

Is there anyone who needs one of these switches I mentioned earlier in the thread? I have changed switches, and ill let mine go. Single switch vs. having to buy a minimum of 10.

I paid $67 and only ordered one. (I will take $50 shipped)

The pressure adjusts from 250 PSI to 1000 PSI. Part # 209506