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brake boosting a TT 350z.

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Old 11-24-2006, 07:29 PM
  #41  
tig488
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i would try it but i have a G35 and we all know those dreaded pins arent always the same between these cars.
Old 11-24-2006, 09:17 PM
  #42  
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Originally Posted by n/a
Sorry guys,
I understand what is being discussed but a little lost with the term 'Brake Boosting'. Could someone explain why this term is used?
while racing from a punch, you get a few cars ahead, and start braking, at the same time gassing the pedal, creating boost, then let go, and ..WOMP~!!. Ive brake boosted in a few supras, its insane, still trying to figure out the 350z, couldnt you just wire up the brakes seperatley from the ecu?? Im just giving idea's...i dont really have a interest in going though rotars, or make a kill switch between the fuse??
Old 11-27-2006, 01:02 PM
  #43  
KPierson
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The voltage at the ECU drops to 0vdc because of a lack of voltage, NOT because of the presence of a ground signal. There should be NO reason to tie the ECU pin to ground. It most likely won't hurt anything, but it shouldn't be necesarry.

What if there was a module that was triggered by the VDC button that disconnected the pin 101 from the ECU? Such a module could monitor the brake input signal, and could send 'fake' signals when the brake wasn't being pushed to keep the CEL light from coming on.
Old 11-27-2006, 02:24 PM
  #44  
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Kevin, i'll take your word on that - I have yet to find the circuit in the service manual that might explain why the CEL is triggered if pin 101 is disconnected. How does it know it's disconnected? I thought maybe it recognized a disconnect vs. grounded signal...

I'd get your VDC memory module in a second if it performed both functions - could it be made to do this?
Old 11-27-2006, 03:53 PM
  #45  
phunk
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Originally Posted by KPierson
What if there was a module that was triggered by the VDC button that disconnected the pin 101 from the ECU? Such a module could monitor the brake input signal, and could send 'fake' signals when the brake wasn't being pushed to keep the CEL light from coming on.
You build it, count me in. However, I would trigger it by the VDC OFF dash light power so that it will disconnect the pin if the car goes into VDC error mode, that way you know its always working no matter why the VDC is shut off.
Old 11-27-2006, 03:55 PM
  #46  
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That light is controlled over the CAN bus, I do believe.

How about a (-) trigger (which the VDC button is, even with the fuse disconnected and a dedicated 'brake cut off' LED?
Old 11-27-2006, 04:02 PM
  #47  
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Originally Posted by KPierson
The voltage at the ECU drops to 0vdc because of a lack of voltage, NOT because of the presence of a ground signal. There should be NO reason to tie the ECU pin to ground. It most likely won't hurt anything, but it shouldn't be necesarry.

What if there was a module that was triggered by the VDC button that disconnected the pin 101 from the ECU? Such a module could monitor the brake input signal, and could send 'fake' signals when the brake wasn't being pushed to keep the CEL light from coming on.
*interested*
Old 11-27-2006, 06:23 PM
  #48  
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I messed around and came up with the hardware tonight, now all I need is some software to make it work.
Old 11-30-2006, 07:38 PM
  #49  
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OK, I have the software done now and I've tested it out a bit (out of car).

There are 5 wires -

Ground

Ignition (12v when car on)

Brake In (From pedal to Module)

Brake Out (From Module to ECU)

On/Off Switch ((-) input, either pushbutton or VDC, should work even with VDC fuse pulled)

Status Output ((-) output to drive LED indicator

When the module is 'OFF' the 'Brake Output' mirrors the 'Brake Input' so the signal acts like normal.

When the module is switched to 'ON' the LED will light continuously, and every time the module recieves a 'Brake Input' signal it only outputs a "Brake Output' for 1s. After that first 1s as long as you hold the brake down the ECU will not get a signal.

The module is designed to reset each time you lift your foot off the pedal, so the ECU will still occasionally recieve brake signals (and thus preventing the CEL).

I've personally never had a problem revving my car while keeping my foot on the brake, so I'm thinking this is either a 350Z think or an auto tranny thing (I have a 6mt G35).

Phunk, you know anyone you can install this thing if I send it your way?
Old 11-30-2006, 08:33 PM
  #50  
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I would LOVE to test it, but first snow JUST landed today!!!!

BTW, I would figure the G35 would do it too? Basically what would happen if I tried to brake boost right now, is it will still rev the engine a little, but it will not let me create enough load to spool the turbos. If you wanna give it a shot, get in like 3rd gear at 5000rpm and floor it, and press the brakes to see if you can get it to hold that RPM/Speed while your still floored - if you can, as you probably know, your car will start building boost like crazy, and when you let off the gas you take off like a bat outta hell - no lag! You will probably just light up the tires actually hehe, i know thats what would happen to me in 3rd gear.
Old 11-30-2006, 09:29 PM
  #51  
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Originally Posted by phunk
I would LOVE to test it, but first snow JUST landed today!!!!

BTW, I would figure the G35 would do it too? Basically what would happen if I tried to brake boost right now, is it will still rev the engine a little, but it will not let me create enough load to spool the turbos. If you wanna give it a shot, get in like 3rd gear at 5000rpm and floor it, and press the brakes to see if you can get it to hold that RPM/Speed while your still floored - if you can, as you probably know, your car will start building boost like crazy, and when you let off the gas you take off like a bat outta hell - no lag! You will probably just light up the tires actually hehe, i know thats what would happen to me in 3rd gear.
I can test it here in San Diego, since there is no snow.
Old 12-03-2006, 04:03 PM
  #52  
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PM'd
Old 12-03-2006, 05:14 PM
  #53  
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I'm in Florida. No snow here.
Old 12-03-2006, 05:37 PM
  #54  
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I'm game for testing it Kevin.....once I get my fuel pressure drop issue fixed.
Old 12-03-2006, 09:50 PM
  #55  
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Originally Posted by KPierson
PM'd
PMed you back
Old 12-04-2006, 12:56 PM
  #56  
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Originally Posted by KPierson
I've personally never had a problem revving my car while keeping my foot on the brake, so I'm thinking this is either a 350Z think or an auto tranny thing (I have a 6mt G35).

Phunk, you know anyone you can install this thing if I send it your way?
Definitely not just a Z thing, I had a 6mt G and could not brake boost.. I wish this topic would have been brought up before, I probably wouldnt have had as much trouble with a certain Evo running around Atlanta.
Old 12-04-2006, 01:00 PM
  #57  
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wait so im not a retard for stalling at the track when i tried to do a brakestance to heat up my tires?

so ANY time i try a brakestance it cuts the throttle?

03 6spd touring.
Old 12-04-2006, 02:01 PM
  #58  
Mike Wazowski
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Originally Posted by nicholasm617
wait so im not a retard for stalling at the track when i tried to do a brakestance to heat up my tires?

so ANY time i try a brakestance it cuts the throttle?

03 6spd touring.

Yes, but your still retarded j/k of course....not really
Old 12-04-2006, 07:42 PM
  #59  
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Originally Posted by USN HM 350Z
Yes, but your still retarded j/k of course....not really
its ok, i know lol.
Old 12-05-2006, 04:33 AM
  #60  
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Originally Posted by KPierson
PM'd
Ohhh I wanna test it You know I'll get good video of it as well...


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