Juicedz

I was wondering how you launch your car with nitrous and a transbrake? When you are holding the transbrake button in, is nitrous spraying? What I was going to do was set my lower limit on my msd two step to 3600 (actrivated by transbrake button) and bring the nitrous in at 3600 through my window switch, which would also ONLY be activated at WOT. Any other ideas or suggestions?
thanks alot guys

Navy David SS

iTrader: (13)

Get a 2 step from Harlan. Tie it into the transbrake. Get a good converter (mine is a 4200). The 2-step will cut off the nitrous until the transbrake it release. I set the 2-step at 4000rpms. Press the transbrake, slam the gas to the floor, release the transbrake on last yellow, 200 shot right out the hole. I BIG word of caution, have the suspension, tires, tuning, fuel to handle it. Using this method, my best times so far (at 3553lbs race weight) is in signature.

David

Juicedz

I already bought a msd two-step, I figure I'll set the low rpm at 3800, bring the nitrous in at 3800 through the window switch, but it is activated on WOT. So I will be bouncing off the lower rev limit, but the car will not be floored. Won't that work? What is different about the Harlan two-step, than the msd?

Navy David SS

iTrader: (13)

The MSD is not (to my knowledge) meant for a multi-coil pack car - at least I "think" the 1995 is still multi-coil pack. All a two-step does is pulse the coil packs, keeping the rpm at the dialed rpm. With the cut-off of the nitrous until the transbrake is released you don't have to think about anything but the light. You system may work, I know mine does . You get the full shot of nitrous at WOT with just a release of 1 button.

David

DERTY

No two step required if you only want to interrupt the solenoids for nitrous. Just wire a relay off the transbrake that when normally closed it provides the ground or 12v for the solenoid relays. When you hold the transbrake it will simply break ground and the relays will not work. When you release the transbrake it will fire right out of the hole. You can use a timing relay to set a delay between the release of the transbrake and the firing of the nitrous solenoids as well.

If you want to have controll over your stall speed on the transbrake, then set a two step up. Otherwise, fire it out of the hole and use a window switch to control your low and high RPM limits.

kevredz

iTrader: (2)

That's interesting about the timing relay. Who would make something like that, and is it a realiable thing to use instead of an adjust. delay box?

DERTY

The timer is called a Digi-Set Make on Brake delay timer. Meaning, it starts timing when electricity to the circuit is broken. The timer is adjustable from .05 seconds to 26 seconds or so. It's very reliable. Cut the transbrake and the timer starts. Whatever you set it to is the delay to the nitrous, yet the car will launch on motor first. I use it when index racing. My car is consistent, but I use the timer to get it to move up or down however much I need. Works great and a lot of other racers use them as well. You can order one from Nitro Dave's or any NX dealer. There are others out there as well. If you are really crafty, you can search for it and buy it from a electronic parts store too. You might find it cheaper too.

BOWTIE

Or just let it spray on the two step while on the brake. If you are running a pro tree, just stage first, engage the transbrake, wait until the other guy stages and then stab it. If the N2O is on a WOT switch it will scare the hell out of the guy next to you and perhaps cause him to red light. If running a sportsman tree, just wait until the lghts are coming down before going WOT. It makes a lot of noise and cool flames from under the car when on a 2 step and the spray at the same time. One word of advice,,, I have not seen this done a plastic intaked or even a fuel injected motor for that matter, but it was cool on a 8 second Super street car.

DERTY

Please don't activate nitrous on a stock piston / rod / crank combo while on the transbrake or even worse, on the two step. Bad things tend to happen. There are guys that do it on forged combos. Just put the car on the transbrake and let the WOT switch start to spray while on the brake. Some guys have managed to cut .1 off their 60' doing that. But if anything hiccups, expect to take a trip to the auto parts store. I just put the car up on the brake, no two step. Then fire out of the hole. Pretty simple.

MeanWS6

What if your window switch is set for say 3000-on, but you transbrake up to say 4-5K but you are still not hitting the WOT switch
Leaves more room for error, I wouldn't have the ***** to do it, but would this still work if you wanted to spray out of the hole without a 2-step or Digi-Set.

DERTY

Even if you are on the WOT switch on the trans brake, as long as the trans brake is wired into a relay it will not activate the solenoids. So even if it stalled at 10,000 rpm it wouldn't matter. It would only activate as soon as you let go of the brake.

You really should be on the transbrake at WOT otherwise it will not be consistent. You can set your window switch at just above your stall speed if you are really worried about it. I just had mine wired to the brake and a TPS wot switch, no window switch. Mat it to the floor, let go of the button and hold the hell on. That simple.

The more crap you put in between the transbrake and the solenoids is only going to slow down the excitation of all the relays and slow down the initial hit. Even with the timing relay, expect to get a .05 delay just in relays switching on and off.

Juicedz

so......... is it possible to "T" my low rpm on my two step to the transbrake to the transbrake button?

DERTY

Yes, you can wire your two step up to activate at a specified RPM below your stall speed while holding the transbrake button. You simply wire the arming switch and the clutch switch to ground when the transbrake is held. I've asked Harlan to make one where the polarity is switched so that you can feed the two step 12v instead of ground to activate it. However, you can run a second relay off the transbrake 12v source to a relay that switches to ground to get what you need. It works pretty good, but it will tamper with the flash point on your converter.

Juicedz

thanks for your help