Lemon Race car Need limiter removed 250GT

[Travis Trayhern]

Hi All

After a hand our lemon 24 hour car is now hitting the speed limiter (first time its gone 190kmph!) at Sandown at the SAU track day on the weekend. 

Car is a 2003 250GT and has the horrid VQ25DD engine, it is running the 6 speed conversion but we are hitting the limiter down the straights now. 

 

We are planning on running the lemons at the Bend so we need it gone. 

Need to know what wires to snip! dont care about speedo working but need to keep the ABS on as we use it for mates to come and have a go at track time so we have amateurs behind the wheel. 

 

 

https://www.facebook.com/anotherdrunkidearacing 

[The Max]

Why not pay a tuner to remove it from the ECU code and while you're at it, get a dyno tune?

[Travis Trayhern]

Show me a tunner that can do this then! 

Not as simple as that it’s a vq25dd I can’t find anything on remaps or rom edits for this ecu. Can’t even find a ecu pinout......

[The Max]

Talk to UpRev or ECUtek about whether or not they support your vehicle's ECU and for a tuner closest to your area.

That's how I do my homework.

[Travis Trayhern]

They don’t hence why I asked does anyone know what wires to snip? Or does anyone have a 250gt vq25dd ecu pin out? 

Cant find anything online regarding vq25dd ecu pin out so any help is appreciated. And yes they are totally different across all the vq models. 

[The Max]

That's surprising.

[admS15]

There's a guy who's cracked the vq25det m35 stagea ecu. Google ITS rom. I know he advertises on ebay, Facebook and is a member on SAU. Cant remember his user name but if you can track him down, would be worth asking him the question and seeing if there's anything he can do for you. Removing a speed limiter should be childs play for him if he can communicate with your ecu.

[Travis Trayhern]

Thank you!!!! Have found him on Facebook 

https://www.facebook.com/ITSROM/

sent a message now to wait for a reply with hopefully a yes! 

[admS15]

Fingers crossed

[BoostdR]

HKS SLD should do it no problems. Part No: 45002-AN002

[Travis Trayhern]

Hi all just an update on removing the speed limiter.

after no help and no options as speed cut defenders rely on an ecu pin out and they just don’t exist for the v35 vq25 and totally different to other vq25 models.

figured let’s start with abs as that’s how it get is speed signal off the wheel sensors. 

First I pulled the abs fuses but speedo still worked, then unplugged the abs ecu still have speedo. Then unplugged the abs motor and the speedo stopped.

pulled the loom back and found that only 5 wires it could be as 2 are power, 2 are negative and then 4 pairs of wires twisted so I assumed they where going to the wheel sensors. So I was left with 5 wires that it could be.

 

Started by by cutting the blue one but wasn’t it.

then cut the red/yellow and it was the one! Abs still works but speedo and speed limiter gone! 

connected they up to a switch on the dash for now so I can switch it on and off, when I have more time I will work out the signal/voltage range and put in and voltage/signal hold at 180. 

[The Max]

You're going to need an oscilloscope, not just a multimeter, as you need to measure the voltage, frequency and duty cycle of the square wave produced by the sensor.