The
RX-7 Diary
I
am now keeping a log of all changes done to the car , so you can see how
much work and time goes into doing a project like this.
22-06-99 :
I have been experiencing a problem with fluctuating fuel pressure for the
past month or so. I pulled apart the Malpassi Fuel Pressure Regulator
and found nothing wrong , put it back together , upped the pressure to
62psi static , and the car is running fine now after a few minor ECU changes
to suit the pressure. Don't you hate these little gremlins...
:-)
23-06-99
: Had a small split inside one of the stainless braided water lines for
the turbo. I managed to get my big clumsy hands down to it and pull
it off , repair and replace. Went for a drive to
test a few things out , but with wet spots on the road from the rain it
was a bit dangerous to do any real testing.
24-06-99
: I will be doing some lambda probe testing on the engine tonight to fine
tune the changes caused by the fuel pressure difference. It is running
a little rich at the moment which at least will not do any harm.
1-7-99 :
Finally have the new turbo that will unleash some of the power potential
of this engine.
17-7-99 : Due
to a split sump and loss of all the engine oil , the triple rotor seized
a bearing onto the crankshaft. The engine is now out
(Pics and story HERE )
, and repairs are being undertaken.
4-8-99 : The engine was stripped
down today by Bill Nabhan at Mazsport. A seized and spun front stationary-gear
bearing is the culprit , with the rest of the engine looking like new.
Lucky....
20-8-99 : I decided to get all
the engine parts either pollished or chromed while it is apart. You name
it , it is being cleaned up. It should be a couple of months , I guess
, before it is all back in the car and running again.
Engine
Designer
The engine originated
from New Zealand and was designed by Jeff Bruce. If you wish
to purchase the parts required to build a similar project, in either 3
or 4 rotor , you can contact him by any of the following methods.
Email :
precisin@ihug.co.nz
ICQ UIN:
15067117
Phone :
+64 09 415 3264
Fax :
+64 09 415 3265
Specifications
Chassis | 1982 Mazda RX-7 Series 2, Freedom Bodystyling kit, Honda NSX Yellow Pearl paint |
Engine | Custom made 3-rotor based on RX-5 13B components, Custom-made Crankshaft, 12A Centreplates with one modified to take a stationary gear, RX-5 end-plates and housings, 3mm Apex Seals. Custom parts made by Jeff Bruce. |
Inlet | Custom-made 6-runner lower section , machined injector mount spacer and fuel rail, Mazda 20B upper Inlet and Throttle Thanks George |
Exhaust | 3-into-1 Tubular Header , 3.5" mandrel bent exhaust system with hand-built mufflers |
Turbo | Garrett T76 compressor wheel in an A/R 0.72 cover, with Q-Trim turbine wheel in a 1.22 A/R housing. |
Intercooler | Custom made by Plazmaman, hand-fabricated aluminium ducting and throttle adaptor. Custom alloy radiator supports. |
Gearbox | Toyota Supra Turbo 5-Speed , Custom "Jeff Bruce" Bellhousing Adaptor, 3" Thick-walled Tailshaft |
Clutch | 6-Puck Brass, Heavy Pressure Plate, Hydraulic Direct-Acting Bearing Caliper |
Diff | Borg Warner 3.45:1 LSD (ex-Holden Commodore VN) |
Radiator | Mazda RX-7 FC Series 5 13B Turbo |
Oil Cooler | Mazda JC Cosmo 20B Turbo |
Fuel System | Electronic Fuel Injection , 6x800cc Mazda 12A Turbo "Green" type injectors, Essex 7.0L/min high-pressure pump and filter, 62psi static fuel pressure, Fuel tank modified with sump pickup. Braided fuel lines with Aeroquip screw fittings. |
Ignition | Direct Fire , 13B Turbo Series 4 Crank Angle Sensor modified to take twin Hall Effect sensors with a 6-window chopper wheel for Main trigger with a single-window chopper for home trigger, 6xBosche HEC715 Coils , 6xBosche "008" ignitors, NGK B9EGV plugs, Magnecor Leads. |
Computer | Haltech custom setup: E6-S8 controlling fuel injection and Lead spark ignition timing. IG5 controlling Trail spark timing. Thanks to the Haltech guys for all the help |
Brakes | Front:10.5" Diameter 1" Thick custom discs
with Volvo 4-Spot Calipers
Rear: 11" Commodore discs , single-spot calipers |
Suspension | Koni Adjustable Shocks, Pedders custom heavy and lower springs, Urethane bushes. |
Wheels | Neale's Wheels ( very soon to be replaced ) |
Interior | Standard Interior. Momo steering wheel , Alpine CD and comprehensive stereo. VDO Boost gauge |
So , you want to know what
it goes like ? It pulls incredibly hard from around 2700 rpm
through to 6500rpm before the turbo becomes a big restrictor. In it's powerband
, however, it is an absolute rocket ! With it's tall diff ratio ( tall
for a rotary ) of 3.45:1, it really gets some speed up in each gear , yet
still revs very fast. It makes the speed very deceptive and you can easily
believe you are not going that quick. That is until you back off and realise
you are doing well past 200km/h in no time. It will easily pass 300km/h
no sweat. In it's current state of tune , it should still be capable
of low 11 second quarter mile times in the 125-135mph range, but please
remember that this car was never intended to run the 1/4 mile. It does
not get much in the way of traction in the lower gears , and as such it's
times would be a lot slower than it is really capable of. So do not ask
me what I think it will do on the 1/4 mile as I am not taking it down the
track. Although it is slippery off the line, the upper gears are mind-blowing!
I need traction big-time now...