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WTF...R32 GTR Speed limited..!..?

PSI_GTSII
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lwells Grand Master

lwells

Posted
Posted
sav man:with the wire cut what does the hicas do?dosnt work altogether or light in dash flashes or what?

The wire is for the speed sensor, so things that rely on speed to activate -- i.e. HICAS -- get confused, which is why cutting the wire = bad.

PSI_GTSII: Your car is obviously fux0red. Give it to me to keep. :cheers:

Lucien.

PSI_GTSII Experienced

PSI_GTSII

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The wire is for the speed sensor, so things that rely on speed to activate -- i.e. HICAS -- get confused, which is why cutting the wire = bad

So if I fitted Power FC what would then happen to this wire.....as I thought the PFC replaced the factory ECU...?

And no Lucien you cannot look after my car :);)

PSI_GTSII Experienced

PSI_GTSII

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The PFC completely replaces the ECU and doesn't have a speed cut: you leave the wire attached.

Sorry I'm confused ;)

Attached to what...?

So you cannot cut the speed limit wire as it makes the HICAS etc go crazy, but if you pull the original ECU out of the car to replace it with PFC, what then is this wire connected to..?

And if nothing, how is that different from just cutting it..?

I will grasp the concept soon I promise :)

lwells Grand Master

lwells

Posted
Posted

Urgh.

The wire is part of the loom that plugs in to the ECU. When you cut the wire, the ECU no longer recieves a speed reading (which is why it doesn't pull fuel) and therefore can't properly activate/deactivate speed sensitive devices, like HICAS.

When you completely replace the ECU with a PFC, the PFC plugs in to the same loom and recieves the speed signal (assuming you haven't cut the wire). However, the PFC is not programmed to pull fuel when the sensor reports 180+KM/H.

Lucien.

Guest Mashrock

Guest Mashrock

Posted
Posted
All jap cars are limited at around 180 kmh ( usualy 185 or so ) .

Bog stock gtrs will hit the speed cutout very easy and depending on model ( if you dont have the limiter ) will go on up to 250 kmh ( r34 gtr ) .

I took my stock 34 to the drag strip ( only mod , catback exhaust ) and i hit the cutout in 4th just after the 400 mt finish line .

i get up to around 220 (i have a 180 speedo) and still have 2 gears left :cheers:

done on a private road also. :)

rukus Grand Master

rukus

Posted
Posted
the speedo is way out at that sort of speed, when i hit the cutout if there was still markings on the speedo it would have shown about 200 so around 15km/h too much. (in r33 gtst)

i had to get my speedo fixed coz of the 18's. speedo was showing 15k/h over b4 i got it fixed

psybic Proficient

psybic

Posted
Posted

Don't know why people are having problems with people saying speed cut wasn't till 200.

My supra and skyline have both speed cut pretty much spot on 200. I can tell this by looking at the speedo and its a damn site closer to where the 200 would be written than the 180 mark.

Maybe they were wrong, but I promise both cars were bloody close to 200km when they hit it.

siksII Grand Master

siksII

Posted
Posted
Don't know why people are having problems with people saying speed cut wasn't till 200.

My supra and skyline have both speed cut pretty much spot on 200. I can tell this by looking at the speedo and its a damn site closer to where the 200 would be written than the 180 mark.

Maybe they were wrong, but I promise both cars were bloody close to 200km when they hit it.

its the speedos, the speed cut as wrxhoon says is in the 180's the speedo is incorrect at those speeds.

u can see how fast u really go by working it out on the rpm u are doing when u hit the cut.

xRHETTx Mentor

xRHETTx

Posted
Posted

If you dont want or need to spend the money to get a PFC, there are plenty of cheaper options to get rid of the speed limiter. Most aftermarket rev/speed meters will override the speed cut. Ive got an old Ultra brand speed meter that does 0-400m ET and top speed and has a trip computer sort of thing, and it cuts it out. Im sure you'd be able to pick up a second hand one for less than $100.

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