In Part One of this series we looked at the evolution of the Toyota Supra
from the late ‘70s to the early ‘90s. In this, the final part, we take a look at
the latest and greatest JZA80 series Supra and discuss tuning potential of the
most popular models...
Mark IV Supra
The JZA80 (‘Mark IV’) Supra was released in 1993 and, as with the previous
series, Toyota invested some serious R&D. Nissan had already established
itself as King of Japanese sports cars with its Skyline GT-R – and Toyota wanted
to knock ‘em off.
But how were they going to do this, you ask?
Simple. By manufacturing the greatest engine ever out of Japan!
Pop the bonnet of a JZA80 Supra twin-turbo and you’ll see an engine that puts
the revered Nissan RB26DETT to shame (in standard form, anyway). The 2JZ-GTE’s
biggest advantage over the Nissan is the sequential operation of its twin-turbo
system – a small primary turbocharger gives excellent boost response at low revs
and a secondary turbocharger is phased in to give strong top-end. Combined with
a 3.0 litre capacity (400cc larger than the GT-R), this system gives absolutely
breathtaking on-road performance.
The 2JZ-GTE is factory rated at 206kW (the Japanese regulation output) but anyone who's ever driven one or tested one on a dynamometer will tell you the factory is being very conservative. The true power figure is closer to around 230kW. But it's the spread of torque that really makes this engine stand out - peak torque is 440Nm and there's a healthy 380Nm at only 1300 rpm!
The twin-turbo engine is most commonly teamed with a 6 speed Getrag gearbox
that allows drivers to launch the 1500-odd kilogram machine to 100 km/h in the 5
second range; not hanging around! If there’s any straight-line
shortcoming compared to the Skyline GT-R there’s one simple reason – the Supra’s
relative lack of traction. With drive sent only to the rear wheels, the big
Toyota can’t lunge off the line with the urgency of the AWD GT-R.
Despite having a Torsen diff, 255mm rear tyres and traction control, the
JZA80 Supra twin-turbo struggles to put its grunt to the bitumen cleanly at low
speed. Fortunately, the aluminium wishbone suspension is very well sorted so the
chassis is nicely balanced – just don’t get too eager with your right boot when
exiting corners... The luxurious GZ Supra twin-turbo is fitted with 2-pot front
and single pot rear calipers while the top-line RZ and RZ-S models feature big
front 4-potters. These fit behind attractive 17 inch alloy wheels.
The JZA80 Supra is a big, bulging machine that’s hard to ignore.
Interestingly, the trademark pop-up headlights of previous models are abandoned
and the rear receives a slightly peculiar looking row of lights. An auto front
spoiler, towering rear wing and removable roof (aka ‘aero top’) is also
available on some models.
Inside, the JZA Supra cabin feels like the cockpit of a fighter plane – it’s
all-engulfing and very cramped. Fortunately, the Supra comes well equipped with
easy to use climate control, power windows and all the other gizmos you take for
granted. Luxury GZ models also score leather trim. See The Supra RZ
for all the details of the JZA80 Supra twin-turbo.
For a less involving driving experience, Toyota also released a naturally
aspirated version of the JZA80 Supra – the SZ and SZ-R models.
Although slower than its twin-turbo stable mate, the naturally aspirated
JZA80 Supra remains a genuine sports car. Tipping the scales at around 100kg less
than the twin-turbo, the atmo JZA80 can get a decent wriggle-on thanks to its
165kW 2JZ-GE engine. The atmo 3.0 litre 2JZ-GE breathes through a DOHC, 24 valve
head featuring a dual-stage variable intake manifold for greater flexibility.
The standard wheel size for the naturally aspirated JZA80 is 16 inches, but many
versions are equipped with optional 17s. An LSD and rear spoiler were also offered
as options. See Supra NA - Realist's Realm for out naturally aspirated JZA80 Supra test.
During 1997 the chassis of the Supra RZ twin-turbo and atmo SZ-R was marginally improved with the introduction of REAS (Reactive Absorber System). Meanwhile, the twin-turbo engine was upgraded to 'BEAMS' (Breakthrough Engine with Advanced Mechanism System) spec. The BEAMS upgrade introduces VVT-i (variable inlet cam timing) to the already potent engine; the result is a jaw-dropping 451Nm at 3600 rpm with the absurdly quoted 206kW peak power figure unchanged. See Engine Ecstasy - VVT-i Supra Turbo for our test.."
Engine Ecstasy - VVT-i Supra Turbo for our test.
Although the JZA80 Supra quickly became a respected performance vehicle, its
extremely high price kept sales at little more than a trickle. And despite the
potency of its engine, the JZA80 also seemed unable to escape the shadow of the
Nissan Skyline GT-R. Production of the Supra ended in 2002 – and
we’ve been without a big Toyota sports car ever since.
Quick Guide to Supra Tuning
The 3.0 litre Mark III and Mark IV turbo models (MA71 and JZA80) are far and
away the most commonly modified Supras. Their relatively large engine capacity,
strong driveline and almost bullet-proof internals make them a great base for
go-fast tuning.
MA71 Turbo
The 7M-GTE powered Supra Turbo is the most popular Supra for modifications –
its relatively low cost, good parts back-up and wealth of tuning knowledge make
it very attractive.
The most basic power-up should comprise a free-flow exhaust and air intake
system. With a quality 3 inch mandrel bent system and modified airbox it’s
reasonable to expect about 10 – 15 percent more power than stock - about 190 to
200kW.
The standard 7M-GTE intercooler is OK in terms of airflow but at
sustained high boost pressure, its thermal efficiency is poor. A monster
aftermarket intercooler (now available from around AUD$450 brand new) is a
worthwhile upgrade that’ll give the scope to generate up to around 400kW without
charge-air temperature or airflow problems.
Next, fit an adjustable boost control system – do a search on the AutoSpeed
site for systems we’ve covered or, alternatively, you can spend more on a brand
name controller. Whatever path you take, we suggest keeping boost below about 14
psi when using the standard fuel system. On some cars, this amount of boost
pressure will require a fuel-cut defender.
With these bolt-on mods – exhaust, air intake, intercooler and boost – your
MA71 Supra Turbo should be stomping out around 225kW along with tremendously
improved mid-range grunt. Expect 13 second quarter mile times depending on
whether a manual or auto transmission is fitted and the available tyre grip.
Beyond this, the standard fuel system should be upgraded. Options are to fit a
rising rate fuel pressure regulator and/or high flow fuel pump, extra injector
system or to upsize the existing injectors. A Lexus V8 airflow meter/560cc
injector upgrade package is a popular way to go.
See Blood Rush to follow the example of a pair of low/mid 13 second Supra
feature cars.
The article Supra-Supreme details further development of one of these MA71 feature
cars. The engine discussed in this article employs a steel crank, 9 litre sump,
improved lubrication system, meaty head studs, upgrade camshafts and various
other parts used in the MA71’s Group A racing days. Producing somewhere around
330kW at the flywheel, this makes an easy 12 second machine (using a tricked auto
trans and slick tyres).
Note that the biggest problem associated with the 7M series engine is blown
and deteriorated head gaskets. There are many aftermarket gaskets that claim
better durability but it is rumoured that merely focussing on head studs and
torque settings fixes the problem.
These are remarkably strong vehicles that can withstand almost anything you
throw at them.
JZA80 Twin-Turbo
The post-1993 JZA80 Supra has an awesome amount of real world performance
potential – even though an ‘all out’ version mightn’t be much quicker down the
quarter than its predecessor. This comes back to similarities in engine
capacity, mass and traction.
But if ever there was a vehicle that comes alive with basic bolt-on mods,
this is it. Whack on a free-flow exhaust from the back of the standard
turbos and up the boost pressure slightly and you’ve got mid 13 second quarter
mile performance.
Note that these two simple engine mods were all that was needed for Craig
Dean’s Supra RZ to claim 3rd outright in the 2001 Targa
Tasmania. See Supra RZ-ing the 2001 Targa Taz for the full story.
Another JZA Supra power-up we’ve covered can be found at Tweaked 2JZ. This particular vehicle is equipped with a cat-back exhaust,
pod air filter and GReddy e-Manage (which holds boost to 12 psi). These
alterations deliver an easy 201kW at the wheels on a Dyno Dynamics chassis dyno
– and, apparently, favourable test conditions give 216kW at the wheels. Given the limited mods, that’s
very serious power.
Note that this vehicle also had its turbochargers rebuilt with steel turbine
wheels; the standard ceramic turbine wheels are known to fail under duress. This
is the only reliability issue affecting the JZA80 twin-turbo.
Finally, see Toyota Six Power! for our article on dyno testing a lightly modified ‘BEAMS’
2JZ-GTE VVT-i. Fitted with programmable management, up to 14 psi boost,
water-to-air intercooling (as used in the engine dyno room) and only the
standard turbochargers, it was seen that 300kW is d-e-a-d easy to produce. What’s
more, the truly awesome spread of torque of the engine is further enhanced – a
stonking 475Nm is on tap from just 2000 rpm. With this sort of grunt, there’s
simply no need to go mad with mods on a JZA80 Supra turbo.
Its little wonder these are such a popular sports car...
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