Is there a 180km Speed Limiter on the American SC400 ?

The 1UZFE EGR Delete Kit is available for sale here.

COFFEE

New Member
Is there an American out there who can help me ?
This may sound crasy but i was wondering if the American version of the Soarer being the true Lexus SC400 was speed limited ?
I do understand there was a lot of differences between the Sc400 and the Soarer.
I thought there may be a chance that it wasn't being built specifically for America.

Any assistance would be greatly appreciated.

Regards

Stephen
 
i think there is a speed limiter-- but i have seen the sc400 go over 140 mph.. thats a bit over 200 kph... i bet the limiter is at 145 mph..
 
Thank you for the reply Chrisman.

Come on guys, there must be one of you Americans out there with an SC400 ?
Could someone please assist me with a sure answer.

Regards

Stephen
 
well they certainly wouldnt have a 180km limit as their gauges are in mph anyway....

hmmm, im guessing someone is thinking of swapping ecu's if they dont have the speedcut??? not sure if it would be possible though....
 
There's an article on Planet Soarer about Harry Lehmans (?) removing the sped cut from the V8 Soarer
 
To all,
Whilst i do know there is ways of getting around the speed limiter by means of installing a piggy back device.
I am some what of a tight as! and dont wish to fork out the dollars especially if there is another way around it.
R-Jay, your a smart cookie thats exactly what i was looking at doing, but i have to work out first if there is the speed lin\miter and where it is at, secondly if the computers can be switched without causing any other issues, thirdly if anyone is willing to swap for a soarer ecu or depart with one cheaply, as i have a spare one.
Zuffen, i will look for Harry Lehmans article but i expect it to be some sort of piggy back set up.
I do actually know of a bloke that will remove the speed and rev limiter for about $600 and both the dash and ecu to do the work but as i said, i am a tight as! and will get out of it i can.

If anyone can further assist me, i would be greatly appreciative.

Regards

Stephen
 
i can imagine there's going to be some minor complications as the US spec 1uz's ran EGR's... you may get away with it.... though i have a feeling it wont be a matter of just swapping over ecu's.....

and if someone actually quoted you that much to get rid of the speed cut, they should be shot.... there products on the market known as "speed cut defenders" which i'm sure will do the job and won't cost very much... you may want to check in the ALSC forums for the quickest and most pain free solution...

like everyone already knows, when it comes to soarer's, those guys know everything.
 
R-Jay,
Whilst i realise this is pricy @ $600 that was a couple of years ago, dont know how much now ?
These other piggy back systems i have read about like the Apexi are about two hundred dollars, i have heard that the auto doesn't shift as good ?

I looked up Harry Lehmans speed cut ecu, it looks the real deal and i am sure it would work perfect along with the extra timing and selectable revlimiter, but $1200. Yeeks

I am in no hurry, ill just keep plodding along, something will arise !
If i could get the Usa ECU to work in my car that would be sweet, it's a factury ecu so gear shifts and everything should work smoothly.

I would expect there to be little issues, i am just hoping they will be nothing to resolve.

What is this erg's i hear you all talk about ?
I expect that it's something to do with pollution ?

Regards

Stephen
 
exactly... it's pollution control.... well, it helps lower emmisions by allowing air into the exhaust (correct me if i'm wrong guys).... it doesn't actually reduce emmisions, it just mixes air into the exhaust to decrease the PPM count of certain molecules.... well, that is my basic understanding of it...

if the egr actually uses air from the inlet system, blocking it off (or in your case, using the ecu on a jdm motor) may result in the a/f ratio's to be a little off..... that is my guess at best.
 
COFFEE said:
Is there an American out there who can help me ?
This may sound crasy but i was wondering if the American version of the Soarer being the true Lexus SC400 was speed limited ?
I do understand there was a lot of differences between the Sc400 and the Soarer.
I thought there may be a chance that it wasn't being built specifically for America.

Any assistance would be greatly appreciated.

Regards

Stephen
As the Lexus SC400 has a speed limit of 160 mph or close to 260 kph, I guess that's plenty enough for the street. There're several factors to reach the speed limit of 160 mph. They could be the tires size, street surface condition, suspension system, ignition system, your foot's timing on the gas pedal, and a healthy engine such as with a supercharger added...etc. Despite all those factors, you could get your SC400 running up to 140 mph, because that's what I did and I think I could go a little faster if the traffic didn't slow down.

If you're talking about the speed rev limiter, then you would search for some IV Supra guys out there. They've been doing that alot for drag racing.
 
Interseting,
I most definately agree about the conditions effecting the top speed and how quickly you get there.
As for the 260kph " Speed Limit " ?
To my understanding these cars max out at that speed ?
Run out of legs rather than speed limited.

Regards

Stephen
 
COFFEE said:
Interseting,
I most definately agree about the conditions effecting the top speed and how quickly you get there.
As for the 260kph " Speed Limit " ?
To my understanding these cars max out at that speed ?
Run out of legs rather than speed limited.

Regards

Stephen
I'm not quite sure if 260 kph or 160 mph is the "Speed Limit" the SC400 can go. However, taking it to the trak will provide the appropriate answer. Just out of curiosity, why are you stating 260 kph instead of 160 mph? I've been residing in California and learning how to measure in miles ever since, even though I prefer kilometer and the Metric system due to its precision over the English system.
 
Most sedan type cars (not supercars) are speed limited to 150MPH or around 250KPH in the interest of safety as at that speed you're starting to approach the limit of the tyres.

The European makers have an informal agreement that the non-performance models in their range are all speed limited to 250KPH.

Keep in mind any accident over 200kmh is a long drawn out episode. You don't want to be in one I can assure you things take a long time to stop banging and crashing. For many years my wife and I always observed a max speed of 200KPH as above this accidents are quite often unsurvivable.

The fastest speed I know of in an accident was calculated at 280KPH by a forensic crash investigator and all 3 persons in the car survived almost unscathed. The car (made of carbon fibre) sacrificed itself for the occupants.
 
Stephen, there's been a number of people wondering about the differences between the US SC400 ECU and the Soarer ECU on ALSC over the years and it's not really do-able. 2 of the main differences are the EMV and the digital dash which won't work with an SC400 ECU.

Harry Lemmens's modded ECU would be awesome but it's stillborn project. It would have given all the flexibility of a fully tunable standalone unit within the standard ECU. Damn shame.
 
R-Jay said:
exactly... it's pollution control.... well, it helps lower emmisions by allowing air into the exhaust (correct me if i'm wrong guys).... it doesn't actually reduce emmisions, it just mixes air into the exhaust to decrease the PPM count of certain molecules.... well, that is my basic understanding of it...

if the egr actually uses air from the inlet system, blocking it off (or in your case, using the ecu on a jdm motor) may result in the a/f ratio's to be a little off..... that is my guess at best.
Opposite way around. It put exhaust air back into the intake to reburn the gasses.
This only occurs while the motor is in full vacuum (idle and decel'ing)

As far as plugging a US Spec ecu into JapSpec harness, there is a 99% chance of it working.
The ECU will bitch and moan that EGR system isnt there, neither are the 2nd o2 sensors, or the o2 sensor heaters, neither is the traction control or the 2nd throttle position sensor, but everything else is 99% the same.
A couple of pins will need to be changed, but not many.
 
You might get the engine to run, but in a Soarer which is what Stephen has there's a lot more to it than fuel and spark. I'll try and dig up the past threads about it on ALSC where guys a lot cleverer than me went through the issues.
 
I was a little worried. The entire thing rear of the car was vibrating-probably due to my worn suspension bushings at the time. 176 was redline but not quite fuel cut.
 
dyno??

I was having that start-rough idle-stall problem after parking in closed in parking stations. If the motor was still warm I would sometimes have to restart 5 times. If there is a breeze around, no problem. I read that a new ecu would fix the problem, it did mostly.
I found a Mines ECU as I have mentioned on another thread. This removes the speed limiter, ups the rev limiter to 7500rpm and increased the power by what feels like quite a margin. I really notice it going uphill, it just pulls with very little throttle.
Circuit Club is puting on a track eve at Eastern Creek on the 26th for $210, the long straight should be fun.
Can anyone help me with an affordable speed shop in Sydney with a dyno, so I can get some real figures?
cheers
 


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