aftermarket ECU's

[Okibi]

Check out the Hydra ECU flyin Miata is offering

- Dave

[Pete IRVING]

Chris,

Been here 3 years ago, firstly trying a Turbo2Link, then a Link plug in
(specific to the MX5) then swapped it for a Link Plus. The only difference
between the latter two is that the Link Plus had more individual switching
functions (vtec/shift light etc, etc) and could be used on higher revving
engines that required more map points. The map point divisions (resolution)
were basically the same.

I turboed the particular car using GTX bits and the older tech, rising rate
fuel pressure regulator, then went to auxilliary injection etc. After
finding that the latter worked so much better than manipulating fuel
pressure and wanting some form of timing retard, I went to a Turbo2Link
computer from Link Electrosystems. These units provide mapped fuel
enrichment with an auxilliary injector, mapped timing control using
intercept type (piggyback) control and mapped electronic wastegate control,
using a standard Subaru type 3 port solenoid valve. The Turbo2Link was
excellent as it only fattened the fuel and provided the necessary retard
where needed so the often tricky areas of cold start/part throttle functions
of the engine were run perfectly by the factory ECU. This provided 180-190
rwhp using the small GTX turbo with a small intercooler.

The only reason I moved on to a stand alone ECU was that I was led to
believe that the factory vane type AFM would provide an unwanted intake
restriction when chasing bigger HP numbers. I now know that 195-200 rwhp
would have been possible using the factory AFM and more using the bigger and
adaptable (to the standard MX5 ECU) RX7 AFM.

The Link stand alone ECU's were a pain to tune properly, mainly in the part
throttle zones and cold start on winter mornings. Using the bigger 440
injectors mean't finnicky idle (even in sequential mode) and more engine
noise (they are very audible at idle...) and the self tuning fuel function
using the factory or better 4 wire lambda sensor, kept changing with ambient
conditions and had to be locked out below a certain RPM. As someone else on
this thread has mentioned, these sytems do not have enough tuning resolution
to acheive good driveablity with map zones at 500 rpm/0.4 bar MAP divisions.

Overall, I was pretty disappointed especially after spending all the time
and money trying to make the standalone ECU's work and knowing the cheaper
and easier to tune Turbo2link, provided similiar numbers and could have been
used to make more power with the RX7 AFM.

The above aside, the aftersales service by Link was (and still is)
excellent.

Bottom line, if you just want around the 200-220 rwhp level of tune, go the
Turbo2link or similiar so you can use the factory ECU with the bigger RX7
AFM. Flyinmiata use the same Link hardware with their own ecu chips on some
of their kits with excellent results. (factory AFM in latter cars went to
superior hotwire type) Reserve the better quality (read more expensive)
stand alone ECU's for the big horspower projects which may require engine
strenghtening anyway...

My 5 cents worth...

Let me know if you are interested in a Turbo2Link as I just happen to have
one.

Pete.
Hawkes Bay.

******************************************************************

[...]

[Darryl Curran]

4x 330cc is just enought for just over 200hp at the engine to be on the safe
side.
rule of thumb 500cc total fuel per 100hp, thats a good idea to go by
Darryl Curran
CBR Motorsport
Bitch'n Performance
Morrinsville 2251
New Zealand
07 889 1613
021 250 5083
bitchnperformance@xtra.co.nz

[Pete IRVING]

Yes, the car was dynoed at over 180rwhp using 12 psi and a pair of 330cc
auxilliary injectors (running in parallel with each other) on top of the
factory 205 cc units.

The benefit with the auxilliary injector setup over running larger units in
the stock manifold is that if you need more injector capacity, you just up
the injector size or add more than one auxilliary injector to up the
injector supply range, without the idle problems.

The armchair purists will argue the possiblity of fuel distribution problems
with auxilliary injectors not being close enough to the ports etc etc, but I
haven't seen any evidence of that with projects I have run with the
turbo2link. A way around that, if you are concerned and can be bothered
with the extra work, is to mount an extra injector in each plenum runner
like the before mentioned Flyinmiata kits, effectively ensuring the fuel
makes it to each individual port.

180 rwhp was OK but I sold the particular turbo MX5 I refer to, 2.5 years
ago and have since gone the transplant route with my current MX5 project. It
runs a Nissan SR20DET engine/trans/rear end.
Again, power has been improved using a turbo2link with modified wiring to
suit this engines 4 coil direct fire ignition system and factory ECU. This
engine makes 330rwhp at 15 psi with a flowed factory BB T28 and usual
mods.(same dyno)

There is more than one way to skin a cat...

Pete.
Hawkes Bay.

[poison]

I'm installing the Miata Link with the Flyin Miata Chip also
due to similar sort of feedback. TradeMe once again for
injectors, I bought some 440cc ones for my conversion but am
considering getting some 330's as from what I've read here
the 330 will give me a better idle. The second good thing is
that if you use the 330's or 440's on a turbo set-up then FM
already have some downloadable fuel maps for this set-up so
you have a great starting point.

The FM knock sensor is $$$ although I've been told I can use
a knock sensor off a turbo diesel from a wrecker. As these
just put out an on/off signal so are compatible across the
board.

Other tip, although cheaper don't buy the NZ ambient air
temp sensor as it's different to the one used in the FM
set-up.

Gazza
"PO1SON"

[...]

[Mike Jolley]

Could have been the tablecloth.I always tell the minister of finance(her
indoors) it cost $100.(a car or a part always $100)This still gets a
suspicious look after 30 years of buying toy cars and over 30 motorbikes for
racingNEVER change a wining formula i say. Mike