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[SloS13]

So, I'm gonna be making an electric cut-out with a Nissan DBW throttle body.  From what I've been able to come up with, it operates off of 5v.  Luckily just providing 5v to it makes it open without needing to worry about doing super nerd shit.

So, I came up with a simple 5v regulator doo-dad (think radio shack) that works on the bench but gets hot quickly.  Keep in mind this thing could potentially be running for 30 minutes at a time.

Should I attempt a heatsink/fan approach or actually spend money and get something more industrial such as this?

http://www.ebay.com/itm/DC-DC-Converter-12V-24V-Step-down-5V-25W-/260726047066?pt=LH_DefaultDomain_0&hash=item3cb47bc15a#ht_2103wt_1270

[Tim]

Most cell.phone chargers convert 12v to 5v. How much current do you need? I know I have a box of em laying around.

[slappynuts]

I think your going to cook that TB. I would go with a standard TB with a cable to some type of motor.

[2point2]

I think your going to cook that TB. I would go with a standard TB with a cable to some type of motor.

yeah, a TB 'motor' is not designed to take the punishment of exhaust heat.  A remote motor setup from any hondas HVAC is 12vdc and that should push/pull a tb cable.

[rawr]

L2ohmslaw

[t_cel_t]

l27805

[SloS13]

l27805

I'm running a variation of one of those, but 3A

The throttle body will be at the rear of the car.  You guys know I'm gonna do it despite your warnings, right?

[HiProfile]

I had this issue when I made a servo-based cutout with a monster servo. It needed a ~6 volt, 3+ amp power supply off 12-15v. My solution - R/C servo power supply, aka BEC or UBEC. They most handle 3 amps continuous, 5-6 amps peak. They also have huge input ranges, such as 7.2v-32v.

I got a servo power supply from an ebay chinaman for $5, waited 2 weeks to get it, then set it to 6v. Most will be set at ~4.8v, or have a jumper for 6v. I somehow found out what resistor to change to alter output voltage, so I made it 7v. If you can figure it out, you could hook it to a small pot and adjust it on the fly. If you want more info or pics, you need to talk to Charlie Moua on hater-tech, I sold it to him.

This is probably the same chip as mine was, just bigger caps: http://www.ebay.com/itm/4A-UBEC-RC-Helicopter-Car-2-6S-Lipo-Battery-Input-5V-2S-/290608428906?pt=Radio_Control_Parts_Accessories&hash=item43a99cb76a


Your ebay auction should work, but there will be zero chance of adjustment.

[SloS13]

I had this issue when I made a servo-based cutout with a monster servo. It needed a ~6 volt, 3+ amp power supply off 12-15v. My solution - R/C servo power supply, aka BEC or UBEC. They most handle 3 amps continuous, 5-6 amps peak. They also have huge input ranges, such as 7.2v-32v.

perfecto.  Never thought of that.  I'll order one of those beasts as an inevitable backup. Thanks 

[Joseph Davis]

This is a bad idea on any speed density car, tune shifts with the cutout.

Internal wastegate actuator to classic cable TB, always opens at a repeatable pressure and the tune is preserved.

IDK what DBW Nissan TB you have, but the FWD and RWD VQ35DE units are a 12-15VDC operated unit and are meant to be PWM. 

[SloS13]

This is a bad idea on any speed density car, tune shifts with the cutout.

Internal wastegate actuator to classic cable TB, always opens at a repeatable pressure and the tune is preserved.

IDK what DBW Nissan TB you have, but the FWD and RWD VQ35DE units are a 12-15VDC operated unit and are meant to be PWM.

1. I like bad ideas.
2. It's a VQ35 TB.
3. Very good to know, that makes things a lot easier.
4. You're knowledgeabilities really are uncontrollable
17. Yeah I could do a boost actuated one but I'm already in this too deep.  Parts are ordered.  It'll be easy enough to remove and re-do if necessary

[Joseph Davis]

Time is money.  You only think you're in too deep.

If I haven't emailed wiring diagrams in the next 24 hours, remind me.

[SloS13]

What exactly are you trying to do?  Not sure what you mean by "cut-out". That term indicates an ignition interrupt or "cut-out" in my mind. If we are talking about a servo actuated exhaust valve, why not use one from a bike like a Kawi, Zuki, or an R1?

They are remote cable actuated and (I believe) are 12v. Basically they are giant RC servo motors.

exhaust cut-out.  Im not thinking one from a bike would be big enough (3" exhaust).  I would have probably finished by now but school started back up.  I'll get to it eventually.

[HiProfile]

I wonder if my e-cutout thread is still in the forum. Mine opens any time there's more than 60% throttle. The ecu activates a relay, and that relay sends a signal back to an ecu input to change maps. That way it won't switch maps early or late.

Using a boost actuator is fail IMO. Mine spooled faster when it opened before boost. Use a vacuum actuator if you really want a "dumb" mechanical system that spools the fastest. The problem there is it needs to be big and adjustable, or you need to use a vacuum switch to activate a solenoid, which routes high vac to it from a vacuum reservoir.