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rev limit? speed limiter in our cars?

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Old 09-07-04, 08:34 AM
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kaotiq
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Default rev limit? speed limiter in our cars?

I was racing a 1.8T A4 yesterday (yes, I know. It is stupid to race, but he started it ) and when my car hit 125 MPH, the car just all of a sudden stopped going and dropped in RPM gradually. I was still able to drive just fine. After that, I was just too scared to attempt that sort of speed again fearing that something is wrong with the car.

My question: Do our cars or motors have a speed limiter or rev limiter?

info on my car: It is has a soarer 1jz swap with BPU.
Old 09-07-04, 12:11 PM
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qtb33
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if you are running the J-spec ECU then by law every car in japan has a ~112MPH speed limiter.
Old 09-07-04, 12:37 PM
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kaotiq
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Originally posted by qtb33
if you are running the J-spec ECU then by law every car in japan has a ~112MPH speed limiter.
is there a way to override that?
Old 09-07-04, 01:10 PM
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Sorta, you can wire in some type of VSS (Vechical Speed Sensor) by pass but you'll lose use of your speedometer, while you have it engaged. Sometime there is also a 5th gear rev limiter which is set just above the factory speed limiter, as I found on my friends 240sx. However, I'm not sure if the 1JZ has this.

Should there be a 5th gear rev limiter you'll be able to find this somewhere on the tranny, you'll need to find out where this is and then you can also by-pass this.

You also need to keep in mind that some ECU's depending on how their logic works this may throw a CEL and put the car in to limp mode when a by-pass is turned on. The ECU may think that a sensor has gone bad and gets pissy. I know OBD-II dose but I dont alot about how Japan dose their's.

The alternative is too go with a aftermarket unit. Being a 1JZ I would assume there is a huge ECU aftermarket and possible a single chip that would delelt the gov and the 5th gear limiter.

Hope that helps

Good luck
Old 09-07-04, 02:26 PM
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kaotiq
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Originally posted by qtb33
Sorta, you can wire in some type of VSS (Vechical Speed Sensor) by pass but you'll lose use of your speedometer, while you have it engaged. Sometime there is also a 5th gear rev limiter which is set just above the factory speed limiter, as I found on my friends 240sx. However, I'm not sure if the 1JZ has this.

Should there be a 5th gear rev limiter you'll be able to find this somewhere on the tranny, you'll need to find out where this is and then you can also by-pass this.

You also need to keep in mind that some ECU's depending on how their logic works this may throw a CEL and put the car in to limp mode when a by-pass is turned on. The ECU may think that a sensor has gone bad and gets pissy. I know OBD-II dose but I dont alot about how Japan dose their's.

The alternative is too go with a aftermarket unit. Being a 1JZ I would assume there is a huge ECU aftermarket and possible a single chip that would delelt the gov and the 5th gear limiter.

Hope that helps

Good luck
thank you sir! i was just told that the rev speed meter is capable of eliminating this problem.
Old 09-07-04, 04:53 PM
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0l33l
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I think that speed limiter is only for cruise control on Jspec cars.
Old 09-07-04, 06:48 PM
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SupraCoup3
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here's a start... http://users.bigpond.net.au/startrad...limiterAp.html



This Japanese-made instrument works well as the maximum speed delimiter for Toyota Soarer 2.5 litre T/T and other makes and models. It also has whole host of other features such as stop watch/lap timer, speed indicator, revolution counter e.t.c.





The Apexi delimiter has a provision for accurate speed calibration to take into account different rim/tyre combinations.

Please note that the reason for inclusion of the LED speed display in the delimiter is the fact that the original Soarer speed indicator in the combination meter stops indicating at 179 km/hr when the car is driven at higher speeds.
Old 09-08-04, 08:00 AM
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kaotiq
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Thanx for the great info. I have a different version of the Apexi RSM. I wonder if they are the same in a sense.
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