Problems

[dangerous brain]

The Aristo was meant to sell yesterday. Unfortunately a niggle came up. I'll paste it in from the supra forum as its such a longy

All aristo's from what I have found out have speed delimiting issues. The MK2's cannot be delimited from the 112mph without changing the ecu. The MK1 on a dyno will hit what can only be described as a secondary limiter when its above 112 mph in a set gear which I beleive is 3rd gear it gets to 5400 rpm and just bounces off a limiter. Change gear ie up to overdrive and problem gone until alot lot faster.

This car because its got a manual gearbox and because it has its original ECU and obviously it has had to be fooled a bit as it expects to get signals from the gearbox which it isnt getting. From what we can gather it is hitting this secondary limiter at 5400 rpm in all gears at speeds lower than the 112 mph. It is only hitting the limiter at WOT if you are building it up like from a standing start. If you drop back from wot by even a centimetre or so it will just head on through 5400 and onto its real limiter over 6500. It will only do this in second if it gets a brilliant start if not its onto third. It will only then do it in third if you keep your foot planted from second again if you lift off a nadge thats it, it wont do it. If it does hit that limiter you change up to 4th it will do it again if you keep it planted to the floor by this time though you are going a tad quick. I haven't had a long enough road or enough balls to keep going and see if it does it in fifth and sixth but my guess is maybe yes.

I am going to try a 6 speed manual supra ECU in the car as that isnt that expensive a fix. If that doesn't work then its time to consider a standalone. Now heres the crux. Is a problem thats very difficult to reproduce and with practice easy to get round by blipping off the throttle at 5000 rpm and straight back on it really worth spending over a grand on to fix with no other agenda than stopping the car from doing it? Bear in mind figure reliability aside the car is making good power at 5400 rpm. If you lose 65 of the 365 quoted from the dyno for pub figure upmanship you are still in good J-spec 2JZGTE territory and thats at 5400 rpm

I could justify the expenditure if the car was going to be taken to big twins, big single, or at a push hybrids. Simplest fix would be to do what we used to do on service landrovers and fix a stop bolt on the accelerator preventing full WOT

Now seb reckons his doesn't do the limiting thing on the dyno and he has a toms ECU. Anyone know where I might get one of those from and what sort of cash are we talking here?

Any thoughts on this issue good or bad would be appreciatted

[rallure]

you have a PM on the supra forum Bry

[Ahhhh__Aristo]

I'm pretty sure I've been above 5400rpm in 3rd with no issues, would you like me to try?? (obviously on a private track)

As I'm not on call tonight and the mota needs a run :D

The bolt behind the loud pedal is a bodge IMHO for such a lovely car.

Is the buyer not wanting it until it's fixed??

Will a supra ecu fit OK?? and not go pop fizzle bang??

[rallure]

im sure we use the supra ECU in the mk1 aristo.

[Ahhhh__Aristo]

Be fine and dandy if we do, and would fix DB's problem cheaply.

Aristo ownership is like a murder mystery-who dunnit film lol

[dangerous brain]

Yeah I have a 6 speed supe ecu winging its way here now. I'm not sure if its compatable. The ECU controls quite a lot of stuff from what I can gather. So I may get the engine working OK with it and the windows or aircon wont work etc. The buyer can't for reasons I won't go into in the interest of confidentiality take the car with any kind of niggles.

To be fair here it only does it if you beast it completely pretty much from a standstill any amount of backing off anywhere along the line and it won't do it. You may also find you have a blitz/mines/toms ecu especially if you've gone BPU and run more than stock boost.

[Ahhhh__Aristo]

I'm stock as they come DB, will try the rub later for you hopefully, but it's just started raining here.

[Ahhhh__Aristo]

OK been out, kept O/D off and took it to between 6k rpm 6.5k rpm, no problems, tried it a few times, never hit anything like a second limiter, although at 5400rpm it's not at 112mph, or just on the verges of it (was keeping my eye more on the road and rpm clock and not the speedo tbh)

Don't know if this helps at all, probably not lol, but hey, I had fun :D

[dangerous brain]

It is exceedingly difficult to get it to do it. probably dyno flat out conditions only and its considerably above 112 mph it does it apparently

[yoshi]

I'd be pretty careful about plugging in a Supra ECU. It should just control the engine and nothing else if it's like the Mk.2 (seperate ecus control aircon, windows etc.)

For proper delimiting, just send your ECU to MINES and for about 600 quid it'll be re-programmed with the speed de-limit and also the boost limit off too. Ignition map will be advanced for quicker throttle response too.

In the end I went for a TOMS ecu for my car, I had to wait about a year to get one 2nd hand. Otherwise I'd have bought the MINES.

[dangerous brain]

Thing is all I need to control is the engine as I haven't got an automatic box that needs controlling anymore :) If a supe 6 speed box fixes it then all the better. I'll let you all know in about 2 hours.

[Robin H]

so what was the out come

[dangerous brain]

Oh yes. The 6 speeder fixes it so yes the supra and aristo ecu's are compatable if you go manual.

[Aristopheles]

Glad you got all that sorted Bry.

[dangerous brain]

Cheers fella. Oh and its pretty damn bloody quick now that it revs all the way to 6700 :)

[Robin H]

Cheers fella. Oh and its pretty damn bloody quick now that it revs all the way to 6700 :)

happy you got it sorted

[chips229]

Hi,

Glad you got it sorted out dangerous and thanks for the info about the Supra and Aristo ECUs ;)

[Ahhhh__Aristo]

Does it feel any different DB?? apart from the limiter fault gone??

Just wondering if the supra ecu is mapped any different.

[dangerous brain]

Well I'm not one to jump to rapid conclusions but yes it does feel a bit peppier.

[yoshi]

I guess that would make sense - as the ECU is just controlling engine/gearbox.

It will feel quicker 'cos the boost will be up a bit and the ignition timing advanced.

But it will need 100RON fuel at all times, otherwise detonation.

[dangerous brain]

Sold again now then to the original buyers good mate :D

[rallure]

But it will need 100RON fuel at all times, otherwise detonation.

98 or 99 ron is fine, if it was the case that it needed to be 100 ron all the supras over near would have problems because most run optimax 98 ron.

[dangerous brain]

Mine was fine on most sul's except sainsburies and that was running 474 bhp on stock tubbies.

Anyways tesco's 99 is cheaper than optimax :D

Sad sight of the day was watching her being driven away by her new owner :(

[Aristopheles]

Has your white one arrived yet, Bry?

[dangerous brain]

Two weeks and its for sale already :)