TOP END is only 200 kph / 124 mph
 

All I can get out of my '89' 3L Turbo is

124 mph or 200 kmh (sorry the title states 142, I mean 124)

there is no tuning - just plain OEM.

Surely this is not right. Could it be something to do with UK Spec cars having a restrictor.

EDIT: My car is UK Spec and so shouldn't have restrictor maybe some UK members can enlighten me on this matter. I found the following info on http://www.btinternet.com/~netsurf/mr2t/mr2tfaq.html

Speed Restrictor:
In Japan there is a legal requirement for all cars to have a speed limiter at 180 km/h, which is equivalent to 112mph. Most Turbo owners report a top speed restricted to approximately 5,250 rpm in 5th gear (about 125mph), and is said to be based around cutting the spark to the engine.
The speed limiter can be removed, and amongst other companies Intech (see above) will do it for approximately ?180 + VAT, or this can be done as part of a Unichip ECU chip upgrade, which typically costs around ?380 + Fitting.
Note: Many owners report that a side effect of having a speed delimiter fitted is that the Power Assisted Steering can become over-light, as the car thinks it is traveling at a lower speed than it actually is. (This is because the speed signal is also sent to the PAS ECU, and is used to judge the amount of steering assistance to be given)
Any removal of the speed restrictor may require a subsequent change of speedometer, as it is reported that the needle will hit the bottom of the dial at about 120mph, and some owners have had problems with needles sticking there !


It sounds like it might be fitted with a restrictor. Its a Turbo and speedometer stays around the 125mph mark. It definately is only doing 124/5mph and is not that the speedometer hasn't been changed after the restrictor was taken off as described above.


Sure the top end of Golf GTI is 145mph. I know it is much lighter car though.

restrictors, in my experience, usually trigger a reasonable amount over max speed limit.. not nearly double. I've had restrictors/governors trigger about 90-95 mph... I think the highest I had was 100.. You said you're stock, and these cars are 20+ years old... 124 mph in 5th gear doesn't sound too far off for a stock ride..

Very disappointed in that. 124mph.

She is in getting a few things sorted as you will see from my other thread. There is a serious miss on her - like she takes a while to catch up on herself.

We'll see if its any different when I get her back.

There is no known model of MKIII Supra with a limiter governing the maximum speed... that article was about the MR2 and that does have a known limiter (at least the JDM and USDM do).

me knows its about MR2.

it was just information on restrictors that fitted the situation.

thanks for info cre, me now knows its got feck all to do with a restictor now. so cre does 124 sound right to you?

Thant's fine. I didn't know if you were just assuming at was an across the board thing for Toyotas or something.

Top speed depends on many factors... I've been up to an over 140MPH (all GPS verified, the stock speedo isn't reliable) in a few different MKIIIs with plenty left in each one. I haven't tried it in a stock turbo MKIII myself, but I know many people have claimed higher top speeds than that.

What happens when you reach 124MPH? Just nothing more to give? Fuel cut? What RPM are you reading then? RPM is a wee bit more accurate than RPM if you know your tire size, transmission gearing and differential ratio.

What market was your MKIII originally sold in? You have a 7M-GTE in there, correct? Do you by chance have Traction Control in the vehicle?

theres nothing more to give at 124mph.

7M-GTE engine.

UK spec.

16x7" tyres - 245/50/16.

no traction control.


just that people are surprised when I tell them the top end of my car, just needed to see what everyone else is getting.

Other than it simply being tired from age and needing a lot of TLC I can't think of anything other than environmental limitations. Like I said though, I haven't tried any speed tests in any stock MKIIIs (I highly doubt I'd feel safe enough), so I don't know what's a realistic cap... I'd think a bit more than that, but it's going to depend on a number of factors.

I really do hope you're exercising due caution when during these attempts and have made sure that your tires and brakes are more than up to the task.

ive personally had my mk2 to 140mph
and my mk3 all the way to 153mph
if most vehicles have a electronic restricter than it will probly slow you around 140-160 km/h
EDIT*
oh and my tires and brakes are prime, not to mention my gauges are fuckin perfect never failed...

So your gauges are good, any need for effing n blinding about it???

Rant aside, the op mentioned he's having problems with a misfire ATM so I'm not surprised it's only hitting 120 or so, in fact I'm more surprised he's pushing it flat out knowing full well that something's not right engine-wise...

I think the quoted top speed (how accurate I don't know) for a 7M-GTE Supra when new was 146mph or thereabouts... I wouldn't be putting this to the test though until I was sure the tyres & crappy single pot calipers were in A1 condition, or replaced with something a little more suitable for hauling up a ton and a half of car from that sort of speed!