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[Leeky]

up to 35 on long motorway journeys

WTF? How the hell do you ever get 35mpg out of a 2jz? its almost impossible. Down hill with engine off?

[Bibbs]

up to 35 on long motorway journeys

WTF? How the hell do you ever get 35mpg out of a 2jz? its almost impossible. Down hill with engine off?

Even doing that with the clutch in, it'll not do that MPG

[Karma Supra]

There was me pleased iwth getting up to 20 mpg.......

[cookci]

mine has cost me a set of brake pads so far in 2 months (rears = £18)

tyres (16" are £50 a corner from mytyres)

Agreed that going from any FWD car to RWD supra isnt easy... infact maybe a little dangerous lol

Why not get a celica SS2? My old SS2 felt faster than my supra and much more practical to boot!

[tbourner]

up to 35 on long motorway journeys

WTF? How the hell do you ever get 35mpg out of a 2jz? its almost impossible. Down hill with engine off?

With ETTC switched on, sitting at just below 60, on a round trip to Nottingham from Portsmouth the average was just below 30mpg (i use pub talk logic to get to a max of 35! :D ).

[Leeky]

up to 35 on long motorway journeys

WTF? How the hell do you ever get 35mpg out of a 2jz? its almost impossible. Down hill with engine off?

With ETTC switched on, sitting at just below 60, on a round trip to Nottingham from Portsmouth the average was just below 30mpg (i use pub talk logic to get to a max of 35! :D ).

ETTC? What and where is this on a mk4 supra?

[tbourner]

up to 35 on long motorway journeys

WTF? How the hell do you ever get 35mpg out of a 2jz? its almost impossible. Down hill with engine off?

With ETTC switched on, sitting at just below 60, on a round trip to Nottingham from Portsmouth the average was just below 30mpg (i use pub talk logic to get to a max of 35! :D ).

ETTC? What and where is this on a mk4 supra?

Electronic True Twin Conversion - wire in a switch in the glove box that forces a ground signal to 2 of the VSVs so they stay open - basically stops tubby #1 coming online until the same point that #2 does.

Some people claim it gives more power and acts more like a big single so I had it done - but more recently I've learnt (both through experience and scientific research!) that in fact it gives the same power and just reduces the spread - it does however make you wheelspin in every gear at 4k revs and no doubt buggers the turbos - so it stays OFF.

Does give good fuel consumption though.

[suprarob]

click here

on the left is a menu click on the FAQ

[tbourner]

Or click here.

You probably can't see this attachment unless you're registered on the forum, but I'll have a go:

http://www.mkivsupra.net/vbb/attachment.ph...54&d=1120502602

Write up on it from resident expert:

You can see the boost pressure curve of both modes of operation. Sequential absolutely kicks the **** of parallel up to about 3350rpm. Then, parallel gets up to 1 bar by 3500rpm, therefore being better for 150rpm. After that, and this is the traction-breaking moment that makes parallel mode *seem* more powerful, there is a really nasty boost spike to 1.3bar - scary when the boost pressure is supposed to be 1.0bar. This lasts for 400rpm before the wastegate opens - the wastegate isn't used until about 3900rpm because the stock ECU doesn't need it to control boost until then - as far as it's concerned, the EGBV controls boost until then.

As you can see, by 4000rpm the wastegate has dragged things back under control and the boost pressure, and therefore power, is exactly the same as sequential mode No higher boost, no magic increase in performance, nothing.

So, parallel gives you:

150rpm (count 'em) of safe higher boost than sequential mode

400 rpm of scary boost spike (the higher your target boost the higher this spike will get as it's basically no wastegate control)

A *lot* less power under 3350rpm

No difference above 4000rpm

Hmmm. You can use parallel if you want but I think it's rubbish.

[Leeky]

hummm, would never do this mod myself. Dont see any point and the standard way it functions its more than fine.

[Karma Supra]

All it does is makes the turbo kicck in more dramatic.... when they eventually do!!!

Incidently playing with my stock, single turbo today... I get usable boost from 2500, not full boost, but useable... thats really not that bad!!!