Stage 1 : Breathing
After hearing from several sources about the effect on
the standard car of changing the Exhaust and Air Filter components
for performance replacements it simply had to be the first step.
Replacement Blitz Air Filters
The improvement was very noticeable, no longer did the car respond
badly at the lower end of the rev range, it was much more lively and fun
to drive without having to keep it high in the rev range all the
time. The exhaust without the extra silencer insert was quite loud
in the car below 3k rpm but above this the droning goes and a good
sporty note is present. The air filters produce a lot of suction
noise at lower revs when the turbos start to spin up which changes to a
high pitched whistle once the car is on song. When you back off
you can get quite a lot of popping from the exhaust and the internal
recycle dump valves of the turbos can be heard. The car now feels
much quicker to 100mph than before. And impresses the crowds from
a distance. :o)
STAGE 2 : Engine Management
Off to DP Motorsport for an APEX AVC-R digital boost controller (the
closest I can get to a R34 dashboard). While fitting this it is
discovered that a Mines VX-ROM ECU has already been installed by the
previous owner in Japan :o)
As the car already had a new ECU fitted it was able to run more boost
safely, during setup it managed a stable 1.25 bar of boost without
any signs of detonation. The only concern is that if the turbos
have not been uprated to metal turbines instead of the ceramic ones then
there is a possibility that the ceramic turbines will shatter.
Because of this the boost is being kept under 1.2bar which is higher
than the recommended 1 bar max for the ceramic turbos, just hope that
they hang together until they get replaced. I have yet to test the
actual performance of the car 0-100 and 1/4 mile, but it feels well
rapid now (when the clutch doesn't slip that is). The standard
clutch should be able to cope with up to 400bhp so either the clucth is
knackered or i'm now running over 400bhp. Hopefully will be able
to get into the 12's this year at USC in August.
STAGE 3 : Nismo Clutch & HKS Downpipes
Again installed at DP Motorsport, the Nismo clutch/backplate and also
HKS downpipes as the standard ones looked a bit small once
removed. Have removed the CAT as well.
Upon driving the car (no, I mean stalling the car) for the first time
I immediately notice that it is now like driving a racing car with a
switch for a clutch, still it is not too bad once you get used to the
sharp responce. However on the good side there is now no slip at
all when driving and you can launch happily above 5k rpm spinning all 4
wheels off the line. The addition of the HKS downpipes and removal
of the CAT seems to have increased the bottom end response and the
turbos are able to produce more boost as I have had to lower the setting
on the AVC-R boost controller to compensate.
STAGE 4 : Wheels & Suspension
The Image 19" 3pc Split Rims with 275/30x19 Contisport tyres are
now fitted and look much better than the standard rims, but the car
needs to be lowered now to look the business. Springs should be
arriving in the next couple of weeks, but not in time for the Doncaster
car show as I had hoped.
First impressions are that it doesn't seem to have
affected the ride quality a great deal, will have to wait and see if the
same can be said of the Blitz spring kit.
The Blitz springs finally arrived and I have fitted
them, my first impressions were that they hadn't lowered the car
enough. However once they had settled it has dropped by approx
30mm and looks much better. The ride over the small bumps has
actually improved on the standard setup, but if you hit some larger ones
you feel the full effect of the hard springs (the M42's a git on the
Stage 5 : Intercooler & Turbos
I decided on the street intercooler from HKS as the race
one was far too expensive for me and only really required at over
600bhp, so this one should suffice for a while yet.
On the road the difference is not really that noticeable
at only 1bar (which shows how good the standard equipment is), I would
expect it to have a more dramatic effect on the track or 1/4 mile.
Once the boost is increased I suspect it will also be more effective.
I have fitted the new HKS 2530 roller bearing turbos and
HKS turbo extension pipes, the smoothness of the car at low revs / boost
seems to have improved noticeably.
The lag before the 'real' boost kicks in seems to be
slightly worse than the standard turbos at around 3500-4000 compared to
between 3000-3500 before, however the boost is held between the gears
much better. The exhaust note has also deepened and loudened.
I will have more info on the overall power feel after having an a/f
meter fitted to monitor the mixture to (hopefully) avoid a meltdown.
The car produced 430bhp @ 1bar of boost at the Tuning Japanese Dyno Day,
the dyno sheet is available for viewing in the Picture Gallery.
Stage 6 : Injectors,
Fuel Management & Fuel Pump
Finally time for some 600cc injectors
and a PowerFC to control it all. These parts were installed and
set up by Abbey Motorsport. Abbey also fitted an adjustable fuel
pressure regulator. I installed the HKS pump before taking the car
to Abbey. I replaced the Mines VX-ROM ECU as it meant having it
reprogrammed and then reprogrammed again if I did any more
The car now produces 496bhp @ 1bar
and 515.5bhp @ 1.15bar. The difference is quite noticeable on the
road as it now pulls from a lower rpm and holds the acceleration right
up to the 8000rpm redline and beyond if you dare to go there ;) I
look forward to the next 1/4 mile day and the top speed shootouts
scheduled for this year to see how it compares. The dyno sheets
are available for viewing in the Picture Gallery.
Stage 7 :
Eventually got round to getting some
new brakes as the originals were really useless, especially after
finishing them off at the Skyline group test at Rockingham. The
fronts were replaced with some Sejoc Grooved Discs / Pagid Black pads,
the rears were replaced with stock discs and DS2500 pads. I also
added a Cusco brake stopper as the bulkhead flexes quite a lot under
braking, also the brake line were replaced with Nismo braided hoses..
I can actually stop again now :o) as
before even coming off the motorway was a bit of a worry as you didn't
know if the brakes would work enough to stop at the end of the slip
road. The only problem is that the Pagid pads really squeal a lot,
i'm hoping this will go away once they have bedded in properly.
The Cusco brake stopper has improved the pedal feel a lot, you no longer
have any pedal travel caused the the bulkhead flexing.
HKS Hard Pipe Kit - Should stop the
expansion/contraction of the stock rubber hoses during high boost/vacuum
moments and increase throttle response (I haven't actually noticed any
difference but it looks nice all the same)
HKS SSQV - A shame that these
really good looking bits of kit are stowed away in the front bumper
where they can't be appreciated, they make a good sound when lifting off
under boost but as they dump to atmosphere the ECU does tend to make
things a little rich while they are open.
Nismo Replica Splitter - I got really bored
with the stock black front splitter as the front end just doesn't look
aggressive enough, now it looks a bit more mean.
TechEdge Wideband AFR Meter - To keep an eye on
the A/F ratio I have fitted a wideband A/F ratio meter, this assists
when attempting to map the car after increasing the boost/flow of the