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Speed Cut At 240km/h

Travis Trayhern
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Travis Trayhern Proficient

Travis Trayhern

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HI everyone, 98 r33 gtr

First off when i got my car went on the net and found that u cut wire 52 i think it was it would remove the speed liminter, rite i did so and yes it worked untill i hit 240 well there abouts, so i joined the wires back up and later on i chipped the ecu and sure enough the limiter was raised to 240km/h again, you hit 6000rpm in 5th and the engine will just die and wont come back into life untill you raise your foot then put it down again. i thought fair enough i should stop being a cheap arse and just get a real ecu like a fc. But my mate has a r32 gtr and he just put in a mines ecu fully baged and sealed and his is doing the same thing has anyone got any ideas i have tried searching but cant find anything on this?

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Travis Trayhern Proficient

Travis Trayhern

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yes well the one i chipped was a mines copy they claimed and was meant to remove it, but my mates was the real deal and the also claim to remove it, and for it to happin to both of us just wondering whats the g o

paulr33 Grand Master

paulr33

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i dont think they can just edit the binary code and remove it, they can only probably set it to the max ceiling limit which would be like 240 or 255

it will be a short integer or something along those lines. as they can't just edit the binary code to say don't execute this part, they just edit the values it looks at, in this case they change it from 180 to the max it will support, so 240/250 sounds about right. a stand alone wont have a speed limit at all, but if you've cut the speed signal wire, then the stock ecu has no idea reference how fast the car is moving

Adriano Grand Master

Adriano

Posted
Posted
i dont think they can just edit the binary code and remove it, they can only probably set it to the max ceiling limit which would be like 240 or 255

it will be a short integer or something along those lines. as they can't just edit the binary code to say don't execute this part, they just edit the values it looks at, in this case they change it from 180 to the max it will support, so 240/250 sounds about right. a stand alone wont have a speed limit at all, but if you've cut the speed signal wire, then the stock ecu has no idea reference how fast the car is moving

The value that the speed lifiter can be raised to is 512km/h

Travis Trayhern Proficient

Travis Trayhern

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The value that the speed lifiter can be raised to is 512km/h

haha yeh i dont think im quite going to hit that limit, but the thing is its not like the speed limiter not the usual barb barb barb it just dies like a total ignition cut untill you take you foot off and the put it bak on again, i also reconected wire 52 and im sure other ppl out there have the same problem and go faster than 240 well i hope or its just our cars dont like us lol

Travis Trayhern Proficient

Travis Trayhern

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oh and another point is that my mates speedo cable snaped a few weeks bak and it made no differance still did it, so it has to be a rev/gear thing that the computer is reading because with out the speedo cable there is no way it can tell the speed unless its something to do with the rpm and gear because like i said with out fail 7000rpm in 4th or 6000rmp in 5th same spot every time.

Keeper Proficient

Keeper

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Posted
oh and another point is that my mates speedo cable snaped a few weeks bak and it made no differance still did it, so it has to be a rev/gear thing that the computer is reading because with out the speedo cable there is no way it can tell the speed unless its something to do with the rpm and gear because like i said with out fail 7000rpm in 4th or 6000rmp in 5th same spot every time.

mine does this too, and its not speed limiter as the speed sensor is rooted in the dash so it cant loop back too the ecu

GeeTR Grand Master

GeeTR

Posted
Posted
oh and another point is that my mates speedo cable snaped a few weeks bak and it made no differance still did it, so it has to be a rev/gear thing that the computer is reading because with out the speedo cable there is no way it can tell the speed unless its something to do with the rpm and gear because like i said with out fail 7000rpm in 4th or 6000rmp in 5th same spot every time.

Speedo cable is meaningless. The ECU takes the speed from the ABS wheel speed sensors. The actual wire that feeds into the ECU is a mean average of the wheel speed sensors from some type of aggregate box (HICAS?) though.

Keeper Proficient

Keeper

Posted
Posted
Speedo cable is meaningless. The ECU takes the speed from the ABS wheel speed sensors. The actual wire that feeds into the ECU is a mean average of the wheel speed sensors from some type of aggregate box (HICAS?) though.

the speed sensor on the dash sends a speed signal to the

HICAS

power steer

ECU

isn't that right?

Travis Trayhern Proficient

Travis Trayhern

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Yeh i have hurd that and something about cutting some circut track on the dash cluster but if it affects the hicas which is usless but its the power steering that might go funny because i think its progressive faster you go the hard it is or something

GeeTR Grand Master

GeeTR

Posted
Posted
the speed sensor on the dash sends a speed signal to the

HICAS

power steer

ECU

isn't that right?

I didn't think so. I figured the hall effect setup on each wheel was used to feed the ECU, HICAS, ATESSA etc, but would be awesome to actually know concretely.

Keeper Proficient

Keeper

Posted
Posted
I didn't think so. I figured the hall effect setup on each wheel was used to feed the ECU, HICAS, ATESSA etc, but would be awesome to actually know concretely.

without the speed sensor on my dash the following happens;

speedometer works (its cable driven)

HICAS failed - so dicked it off

Power steering is locked into high speed mode, it actually starts the car in low speed and then kicks over after about 30 seconds or so.

ECU cannot detect speed signal to feed to consult

ALTESSA works

ABS works

not sure what happens with the sensor in as i am having problems finding one for an early model GTR r32

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