Mazda RX-7 - CHASSIS;DRIVELINE; Explanation and Description of Competition Parts

CHASSIS/DRIVELINE
l. Explanation
and Description
of
Competition
Parts.
A. Clutch
components.
Clutch cover,4352
16 410
To
eliminate
clutch
slippage, this
clutch has
a boss-type
drive
in-
stead of
the straight-type
drive,
and the working
pressure
has
been increased
from
380
kg
to
630
kg.
Additionally,
it has
a
chrome-plated
release
collar
bear-
ing.
Clutch disc,4352 16
460
This clutch
has
a solid center
sec-
tion
without
any
shock
absorbing
springs. The friction
material
is
V-782-J,
specially
selected
for
fade resistance,
and the
boss
spline is
chrome
plated.
Clutch master
cyl
inder.
This
is
the
same as the
stock
part,
but due to the
size of lhe vacuum
assist diaphragm
for the
brakes,
the clutch master
cylinder
must
be
relocated
for
clearance.
4.
Clutch release cylinder,
435241920
This
is
an adjustable
release
cyl-
inder
with a
piston
diameter of
1 1/16".
B. Transmlssion.
These
are the
gear
ratios
of the
stock
five-speed transmission
compared
to
the competition version:
Competition
trans:
4352-03-000
(0.839)
8570-03-000
(0.881)
l. Transmission
case,435217 100A
This
case
is
cast
aluminum with
sections 1.4 mm thicker
than
stock
(up
from 4.6 mm
to 6.0 mm),
for
increased
strength, and it has
a
starter motor
bracket to
support
the starter
on both the front
and
rear
ends.
2. Extension housing, 435217
331
As with the
transmission
case,
the
extension housing is
also
thicker through the
sections. The
speedometer
gear
and back-up
lamp
provisions
have
been elim-
-,.
,,
gua!
lL
inated,
and the
end
bearing is a
needle roller
instead
of the
stock
brushing.
Transmission
mount,
4352-39-340
Compared
to the
stock version,
this mount is
made
of
harder
rub-
ber.
Main drive
gear,
435217
201
The competition
main
drive
gear
has
a chrome
plated
spline for in-
creased
wear resistance.
Synchronizer
ring, 435217
245
To increase
rigidity,
the
synchro
cone
diameter has
been changed
for
1st, 2nd,
3rd
and 4th
gears,
from the
63 mm
of the
stock ver.
sion to
62
mm.
as shown in
the
il-
lustration.
Cone diameler
(dimension
A)
Competition
62
mm
Stock
63
mm
6.
Synchronizer
key
and key
spring,
key:4352
17
243
spring: 435217
244
The increased
working
preload
of
these
parts
improves
the
synchro
action. These
parts
are
applicable
to
1st-2nd
and
3rd-4th
gears
only.
For
Sth-reverse,
the key
and
spring
are the
same
as stock.
The
key
dimensions
are
given
in
the illus-
tration
below:
Groove depth
Comp.
parts:0.7
mm
Stock
parts:
1.5
mm
Gear bearings.
Needle roller
bearings
are
used
on 1st,2nd,3rd
and 5th
gears.
Shifting forks,
1st-2nd:435217
4O2
3rd-4th:435217
4O4
Sth-Rev: 435217 406
1.
3.
4.
5.
2.
3.
7.
8.
1st 2nd
3rd
4th
5rh Rev.
Competi-
tion
2.3501.608
1.2401.000
).881 0.839 2.26
Stock 3.6742.2171.432
1.000
0.825 3.54