How to wire a Two Step and a Transbrake?
- Thread starter 1of1547
- Start date
- Joined
- Feb 18, 2006
I did something similar but not with a trans brake.
http://www.turbobuick.com/forums/general-turbo-buick-tech/326029-ultimate-launch-set-up.html
http://www.turbobuick.com/forums/general-turbo-buick-tech/326029-ultimate-launch-set-up.html
That was my game plan. But TurboBob says the two should be used with a relay so the 2 Step doesn't get a voltage surge when the brake is released. I was always told a relay doesn't release fast enough. Has anyone wired them direct with good results?
Cool thanks for the link.
I have wired them direct. I'm not an electronics guy, but I would think the better solution is to put something on the 2 step circuit to prevent the spike problem.
I have mine hooked up on a relay. There may be some extra delay, but I just wanted to test it out and not worry about damaging the 2 step. Doug, you can ask Paul about the wiring but as long as you know the wiring for the relay, its pretty straightforward. One wire goes to positive, one goes to ground, output goes to the brown and gray wires on the 2step, and switched power to the output side of the transbrake button. The main thing is to know which wire is which on the relay. When its working, you'll also see the Trig LED turn on inside the 2step box (with the cover off) when the tbrake button is pressed.
Some other things.... make sure you use a good ground for the 2step box, make sure you plug the fuse adapter into the CCCI fuse with the wires pointing right, and I like using the 500rpm partial stutter setting (you'll need to set your launch rpm 500rpm higher with this on). For the timing retard, you'll need to play around. With more timing retard, you'll likely leave with more boost at the same rpm. So it depends on how hard you want to leave. And it does continue to build boost while you are on the limiter, so if you don't have an electronic boost controller you'll need to be aware of how long you are on the limiter at the tree. Just some of my observations from the short time I've used it.
Some other things.... make sure you use a good ground for the 2step box, make sure you plug the fuse adapter into the CCCI fuse with the wires pointing right, and I like using the 500rpm partial stutter setting (you'll need to set your launch rpm 500rpm higher with this on). For the timing retard, you'll need to play around. With more timing retard, you'll likely leave with more boost at the same rpm. So it depends on how hard you want to leave. And it does continue to build boost while you are on the limiter, so if you don't have an electronic boost controller you'll need to be aware of how long you are on the limiter at the tree. Just some of my observations from the short time I've used it.
If you look at TurboBuRick's thread, he has a relay to shut off the alky with the 2step engaged. With a Razor kit, you could also play with some of the settings so that the alky doesn't come in so hard. You can raise the turnon point, but better may be turning down the initial some. You can turn the gain knob up a little higher to make sure you still have the same alky up top. Changing these settings may give you some partial throttle knock on the street, so be careful. If you have wideband control, no big deal as long as it can pull enough fuel down low when the alky comes in.
Like I posted earlier, you should use a digital relay if you are going to race competitively. We ran across this years ago when guys used to use a relay on the TB. I would wire the relay like this:
30 12 volt
87a alky
87 2 step
86 transbrake
85 ground
The Bailey Engineering 2-step has 2 trigger inputs.
These inputs do have spike suppression built in, but we have had a couple units that had their trigger inputs die from direct connection to a 2-step or a trans brake.
Protecting the 2-step is easy, and can be accomplished with a couple radio-shack parts.
See attached.
For those who want something already pre-fabbed, I have assembled a few of these and can send them to you. Please contact the distributor where you got the unit.
Bob
These inputs do have spike suppression built in, but we have had a couple units that had their trigger inputs die from direct connection to a 2-step or a trans brake.
Protecting the 2-step is easy, and can be accomplished with a couple radio-shack parts.
See attached.
For those who want something already pre-fabbed, I have assembled a few of these and can send them to you. Please contact the distributor where you got the unit.
Bob
I think disabling the green MAP input would be better. That way there is no spiking of power to the alky controller.
Example
30 Map green wire to map
87a Map green wire to PAC
86 transbrake/2 step
85 ground
30 and 87a are normally shorted on the relay. When terminal 86 gets +12 it makes the relay "click" and open the map connection.. and disables the alky kit from activating.. once you release the power from 86.. relay un-clicks back to normal and PAC gets the MAP signal.
Is this better?
I wouldnt spray methanol into an engine that is mis-firing intentionally. This could pre-ignite the alcohol and create a backfire.
i know. its just a PITA, i was just out in arizona few weeks back wiring things up. now i have to do it agai. no big deal as this should be the last time. got to go back anyways and install my new driveshaft. anyways this is a good post and a fix.
Didnt you call me on this?
I was unaware of issues with the spike back feeding.. makes sense now that I think about it.
But I understand the input on the 2 step is electronic. So when you use a relay/switch on a typical solenoid.. it would not normally be an issue.
Guess if you used multiple relays of the same switch it would also eliminate any chance of issue.
One relay for T-brake, one relay for 2 step, one relay for alky disable. This way there is no back feeding possible. The common would be the pushbutton switch and the relay coils. The alky and 2 step can use smaller relays as what is being disabled is very low current.
Yep, Been there and done that. Just follw the PDF instructions Bob put on here, Took all of 10min to install. Used it Saturday and it works like a charm!
