Drag Racing Tech
Sponsored by:
Sponsored by:

Msd 2 step and trans brake ??

Thread Tools
 
Search this Thread
 
Old Oct 22, 2013 | 12:52 PM
  #1  
bigbrdf250's Avatar
Thread Starter
On The Tree
iTrader: (2)
 
Joined: Nov 2012
Posts: 119
Likes: 0
From: Richmond, Texas
Default Msd 2 step and trans brake ??

So I installed my 2 step in with my trans brake w/o any relays, I just spliced in to the power wire after the momentary that's switched to 12v. It worked for a few test runs and then stopped working. Looks like I either messed it up or had a unit fail on me. the led light stayed lit saying it was activated but neither the trans brake or 2 step worked.

Either way a new one is being sent so how do I go about installing it? I think it would work this way but not sure if I should try another way cause I had a bad unit or I wired it wrong??

It's an msd 8733 and is activated by just a 12v source or ground circuit.
Reply
Old Oct 23, 2013 | 07:40 AM
  #2  
3fingas's Avatar
9 Second Club
iTrader: (16)
 
Joined: Jun 2007
Posts: 495
Likes: 1
From: Weston, FL
Default

Activation switch to trip a 12v/20a relay, power leg (87) to trans button, button to Brake/2step.
Reply
Old Oct 23, 2013 | 08:07 AM
  #3  
Ed Wright's Avatar
9-Second Club
iTrader: (1)
 
Joined: Feb 2002
Posts: 3,397
Likes: 9
From: Tulsa, OK
Default

You think not having a relay caused the Trans brake solenoid to fail? How? Too much load might damage the button, not the solenoid. I don't know of anybody using a relay for that. What kind of button?
Reply
Old Oct 23, 2013 | 08:35 AM
  #4  
3fingas's Avatar
9 Second Club
iTrader: (16)
 
Joined: Jun 2007
Posts: 495
Likes: 1
From: Weston, FL
Default

Originally Posted by Ed Wright
You think not having a relay caused the Trans brake solenoid to fail? How? Too much load might damage the button, not the solenoid. I don't know of anybody using a relay for that. What kind of button?
I don't know why it failed but that's the way to wire it. You use an activation switch to avoid unintentional engagements.
Reply
Old Oct 23, 2013 | 09:14 AM
  #5  
Ed Wright's Avatar
9-Second Club
iTrader: (1)
 
Joined: Feb 2002
Posts: 3,397
Likes: 9
From: Tulsa, OK
Default

Yes, you need a switch to activate it. I'm wondering why somebody thinks it needs a relay. Most guys, where I race, use an adjustable button to adjust our lights on a given day. No relays allowed. Has to be an approved button, wired direct. Can not imagine why anybody would think a relay is needed anyway.
Reply
Old Oct 23, 2013 | 11:45 AM
  #6  
RENE'S RAGE's Avatar
9 Second Club
iTrader: (96)
 
Joined: Nov 2007
Posts: 2,387
Likes: 3
From: Memphis, TN
Default

No relay need, just slows down reaction time.
Like Ed said, probably the button gone bad.
The 2step and TB are two separate components.
Reply
Old Oct 23, 2013 | 12:27 PM
  #7  
bigbrdf250's Avatar
Thread Starter
On The Tree
iTrader: (2)
 
Joined: Nov 2012
Posts: 119
Likes: 0
From: Richmond, Texas
Default

Originally Posted by Ed Wright
You think not having a relay caused the Trans brake solenoid to fail? How? Too much load might damage the button, not the solenoid. I don't know of anybody using a relay for that. What kind of button?
It's a hurst pistols grip with activation button.
Well the way I wired it getting power for activation was spliced into the trans brake wire that also gets activated when switch is pressed. I just don't know if it was a bad connection or bad unit all in all.
Reply
Old Oct 23, 2013 | 01:58 PM
  #8  
Ed Wright's Avatar
9-Second Club
iTrader: (1)
 
Joined: Feb 2002
Posts: 3,397
Likes: 9
From: Tulsa, OK
Default

The button on the shifter handles are normally used for the line lock. Trans brake is normally a different, higher amp button.
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

 Verdad Gallardo
story-1

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-2

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-3

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-4

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-5

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-6

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
story-7

Awesome K5 Blazer Restomod Comes With C7 Corvette Power

 Verdad Gallardo
story-8

10 Camaros You Should Never Buy

 
story-9

10 LS Engine Myths That Refuse to Die

 Verdad Gallardo
Old Oct 23, 2013 | 02:00 PM
  #9  
RENE'S RAGE's Avatar
9 Second Club
iTrader: (96)
 
Joined: Nov 2007
Posts: 2,387
Likes: 3
From: Memphis, TN
Default

See if your button is good.
You can OHM it out, if you have a OHM meter.
Or if you have a test light or dc voltmeter, just put 12volts to one side of the button and see if you have 12 volts coming off the other side.
Reply
Old Oct 23, 2013 | 02:02 PM
  #10  
bigbrdf250's Avatar
Thread Starter
On The Tree
iTrader: (2)
 
Joined: Nov 2012
Posts: 119
Likes: 0
From: Richmond, Texas
Default

My other question was should my power wire to the trans brake when not engaged have continuity to ground??
Switch not pressed red wire = has continuity to ground
Switch depressed red wire switches over to 12v activates power side of tb solenoid

Is this right??
Reply
Old Oct 23, 2013 | 02:33 PM
  #11  
RENE'S RAGE's Avatar
9 Second Club
iTrader: (96)
 
Joined: Nov 2007
Posts: 2,387
Likes: 3
From: Memphis, TN
Default

There is a possibility that it could read to ground, by going through the solenoid windings,
because the other side of the solenoid is grounded.
I would unwire the tb and button and read and see
If your getting continuity between the solenoid.
Also see if your getting continuity through
The button when it is pressed.
Reply
Old Oct 23, 2013 | 02:33 PM
  #12  
Ed Wright's Avatar
9-Second Club
iTrader: (1)
 
Joined: Feb 2002
Posts: 3,397
Likes: 9
From: Tulsa, OK
Default

One wire from the button to 12 volts. Other wire from the button goes to the power wire on the Trans brake solenoid. Other wire on the Trans brake solenoid goes to ground. The wire from the button to the solenoid also goes, if you have a 2 step, to the 2 step terminal on your MSD box. It's only on while the Trans brake button is pressed. Simple.
Reply
Old Oct 23, 2013 | 05:12 PM
  #13  
subhumanzz's Avatar
9 Second Club
iTrader: (46)
 
Joined: May 2006
Posts: 1,037
Likes: 0
From: Fredericksburg, VA
Default

I've had mine wired without relays for a couple years and never have had a problem.
Reply
Old Oct 23, 2013 | 10:10 PM
  #14  
bigbrdf250's Avatar
Thread Starter
On The Tree
iTrader: (2)
 
Joined: Nov 2012
Posts: 119
Likes: 0
From: Richmond, Texas
Default

Originally Posted by Ed Wright
One wire from the button to 12 volts. Other wire from the button goes to the power wire on the Trans brake solenoid. Other wire on the Trans brake solenoid goes to ground. The wire from the button to the solenoid also goes, if you have a 2 step, to the 2 step terminal on your MSD box. It's only on while the Trans brake button is pressed. Simple.
That's what I thought, so that's how I wired it.

Oh and one more thing that can be of great importance... It's a PRO TREE BRAKE on a th350 so maybe the wiring could be different??
Reply
Old Oct 24, 2013 | 04:56 AM
  #15  
subhumanzz's Avatar
9 Second Club
iTrader: (46)
 
Joined: May 2006
Posts: 1,037
Likes: 0
From: Fredericksburg, VA
Default

It should be wired as laid out in your quote.
Reply
Old Oct 24, 2013 | 09:56 AM
  #16  
93camaro_zzz's Avatar
12 Second Club
iTrader: (13)
 
Joined: Nov 2005
Posts: 2,211
Likes: 3
From: San Diego, Ca.
Default

I have my transbrake button wired to that same hurdt button on top like you. It is made for transbrake use, I know that. It is even labeled in the directions as a transbrake switch. I haven't had a problem with mine yet, but I also don't have my 2 step hooked up in the car yet.
Reply
Old Oct 24, 2013 | 09:27 PM
  #17  
bigbrdf250's Avatar
Thread Starter
On The Tree
iTrader: (2)
 
Joined: Nov 2012
Posts: 119
Likes: 0
From: Richmond, Texas
Default

Originally Posted by RENE'S RAGE
There is a possibility that it could read to ground, by going through the solenoid windings, because the other side of the solenoid is grounded. I would unwire the tb and button and read and see If your getting continuity between the solenoid. Also see if your getting continuity through The button when it is pressed.
Ur right trans brake solenoid power wire is making ground when button is not pressed.
Is that normal or how do I fix that??
Could that be y my box went out or just a coincidence?
After hooking my new box up its working just don't know for how long.
Reply
Old Oct 25, 2013 | 09:40 AM
  #18  
RENE'S RAGE's Avatar
9 Second Club
iTrader: (96)
 
Joined: Nov 2007
Posts: 2,387
Likes: 3
From: Memphis, TN
Default

I think what's it doing is reading between the coil windings in the tb solenoid.
Which would be normal.
I'll ohm mine out tonite and see what kind of reading I'm getting.
It seems like you had it wired right the first time.
You do have a fuse protecting the tb hot wire don't you.
Reply
Old Oct 25, 2013 | 10:27 AM
  #19  
bigbrdf250's Avatar
Thread Starter
On The Tree
iTrader: (2)
 
Joined: Nov 2012
Posts: 119
Likes: 0
From: Richmond, Texas
Default

It does have an inline fuse. Check on that for me would u, thanks guys for y'all's help thus far.
Reply
Old Oct 25, 2013 | 12:01 PM
  #20  
3fingas's Avatar
9 Second Club
iTrader: (16)
 
Joined: Jun 2007
Posts: 495
Likes: 1
From: Weston, FL
Default

Originally Posted by RENE'S RAGE
No relay need, just slows down reaction time.
Like Ed said, probably the button gone bad.
The 2step and TB are two separate components.
I use a relay cause I'm not pushing 20 a through a toggle. As far as slowing reaction time. You tell me how much it's slowed. Lol
Reply



All times are GMT -5. The time now is 10:20 PM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE