HoldenGemini.net : Technical Information

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TECHNICAL INFORMATION : Gemini Model Features and ID

TX GEMINI: PRODUCED = March '75 - March '77
POWER OUTPUT = Pre ADR 27A = 63kw Post ADR 27A = 61kw (ADR27A = Nov. '76)
TRANSMISSIONS = M20 4 speed ISUZU manual / M40 three speed 'Tri-Matic' (option)
DIFF = 3.89 Borg-Warner
MODEL CODES = 8TE69 - Sedan / 8TF69 - SL Sedan / 8TF27 - SL Coupe / 8TF27 (opt. A8T) - SL Fashion Pack Coupe
ORIGINAL PRICES - Sedan = $4026 / SL Sedan - $4335 / SL Coupe - $4482

The TX series Gemini was Holdens first world car. In Germany it was the Opel Kadett, U.K the Vauxhall Chevette, U.S.A the Chevy Chevette etc. etc. All cars shared the same 1.6L SOHC engine (coded the G161Z), this was chain driven and incorporated a cross-flow alloy head. A two-barrel 'Nikki' Stromberg carburettor, a cast-iron free flow exhaust manifold, with two outlets into a 'Y' pipe (this item is commonly used by modifiers for later models). From Nov. '76 this was changed to a single outlet exhaust header.

Transmission was a 4 speed manual, with an option of a 3 speed Australian built 'Tri-Matic'
auto. SL models added a push-button AM radio with a single rear speaker, electric clock and cigarette lighter. Factory fitted air-con was optional. SL's were fitted with pinstriping, stainless sill mouldings, side window frames were blacked out and had mouldings along the top of the doorframes. 'Fashion Pack' options were coloured plaid-trim seats and door trim inserts. Early models rear panel badging read 'Holden Isuzu', this was later changed to 'Holden Gemini'. Coupes had different tail-light arrangement from sedan, with smaller separate reverse lights.

All models had 13" X 4.5" steel wheels. Rear brakes were duo-servo units, very similar to
those fitted to 6 cyl Toranas. Early models used the MSE-type four speed gearbox; reverse
was positioned to the 'left and back'. Nov. '75 saw the introduction of the MSG-type four
speed, reverse on this transmission was to the 'right and back'. The TX SL sedan was voted Wheels car of the year' for 1975, and was the most popular 4-cyl car on the Australian market.

TC GEMINI: PRODUCED = March '77 - April '78
As for post ADR27A TX series Gemini
MODEL CODES = As for TX Gemini including, 8TF69 (opt. A8T) -
SL Fashion Pack Sedan / 8TF69 (opt. A9W) - Sandpiper Sedan / 8TF27 (opt. A9W) -
Sandpiper Coupe
ORIGINAL PRICES = Sedan - $4925 / SL Sedan - $5290 / Sandpiper Sedan - $5540

TC was a minor facelift of the TX, appearance was enhanced by a bolder vertical bar front grille, and at the rear by a silver garnish panel (TX was black). A new 'Smiths'
heater/demister/ventilation system was used. The two small vents at the end of the dash were excluded in this line-up, except on those with air-con these vents were retained.

Fashion Pack was now available on sedan as well as the coupe. This option was also upgraded to add steel belted radials and a front stabilising bar (opt. A9R). Door side impact beams were introduced; SL coupes now had a heated rear screen.

One month after the release of the TC, a limited edition 'Sandpiper' was introduced.
Both coupe and sedan version were on offer, they were identified by a black grille with stainless top edge, gold pinstriping, check cloth inserts in seats and door trims,
wood-grain dash inserts, radio/cassette, four spoke steering wheel, and the A9R suspension package. Externally they were easily distinguished by the word Sandpiper' and a bird decal, this was on the side rear quarters of the coupe, and on the rear doors of the sedans.

TD GEMINI: PRODUCED = April '78 - October '79
As for post ADR27A TX series Gemini
TRANSMISSIONS = As for TX/TC Gemini including, M75 5 speed manual
DIFF = 3.90 Holden small Salisbury
MODEL CODES = As for TX/TC Gemini including, 8TE70 - Panelvan / 8TF15 - Wagon / 8TF69 (opt. A8P) - SL/X Sedan / 8TF69 (opt. A8J) - SL/E Sedan / 8TF27 (opt. A8J) - SL/E Coupe
ORIGINAL PRICES - Sedan = $5330 / SL/E Sedan - $6380

The most major change to this model of Gemini was the addition of R.T.S (Radial Tuned Suspension), as well as the availability of a 5 speed manual transmission. Differential was now the small Salisbury unit as fitted to the UC Torana range, it used tapered Timkin wheel bearings as found on all larger Holdens since mid '71. In April '79 the rear brakes were changed to the Commodore's leading-trailing rear drum brake assemblies.

Cosmetic changes included a new simpler grille, rectangular head-lights (round on base models), wheels were now 13" X 5", number plate relocated to above rear bumper (as opposed to below). A panelvan and two-door wagon were now available for the range.

SL/E used many interior options from the TC Sandpiper series, such as radio/cassette, four spoke steering wheel, timber dash inserts, velour seat trim, cut-pile carpet and timber door trim inserts. Externally it had stainless head-light and grille surrounds, thick stainless door window frame mouldings and GM-H designed alloys similar to Sunbird SL/E. Coupes and sedans had colour-coded side mirrors similar to those of Sunbird SL/E and HZ Sandman, door-trims went to the top of the doors.

SL/E was replaced by the SL/X in early '79; it had a slightly lower equipment level but a much better price. Limited Edition 'Gypsy' package was optional on panelvans which included extra instrumentation and identifying decals.

Heated rear screens now standard on all but base sedans, panelvans and wagons. Nylon plaid cloth inserts available on SL's and wagons, Air-con was now available as an accessory.

TE GEMINI: PRODUCED = October '79 - March '82
POWER OUTPUT - 1.6L Petrol = 50kw / 1.8L Diesel = 40kw
COMPRESION RATIO - Petrol = 8.3:1 / Diesel = 21:1
TRANSMISSIONS = As for TD Gemini including the M76 5 speed manual for the Diesel series
DIFF = As for TD Gemini including the 3.58 Isuzu Diff for Diesel models
MODEL CODES = As for TD Gemini including 8TF69 (opt. A9H) - SL/X Sedan / 8TF69 (opt. A9W) - Sandpiper II Sedan
ORIGINAL PRICES - Sedan = $6240 / SL/X Sedan = $6890

TE series involved major sheet-metal design changes from previous Gemini's; front and rear styling was all new, with a squarer slightly larger appearance. Chassis and mechanical mods were kept to a minimum. Bumpers were square style chrome with rubber ends; park lights were vertically mounted at ends of the grille similar to (VB) Commodores of the time. Major interior changes included all new instrument cluster dash, with two large and two small dials and re-arranged warning lamps. SL/X sedans gained improved seating incorporating adjustable head restraints in the front and high-backed rear seat squabs. Coupe was no longer available as was SL/E models.

Early '81 saw the introduction of the 1.8L Diesel model based on the SL/X, it was only available with the M76 5 speed manual. Wagons and panelvans were not released until February '80. Sandpiper returned as the 'Sandpiper II' in June '81 and 'Gypsy' panelvan was made a regular production option. Due to increased demand for the dealer-fitted Air International air-con system, the Diesel-Kiki was phased out during the TE production run.

Manual gearboxes used were revised with slightly different ratio's and diesel model contained completely new ratios. Changes were made to anti-pollution equipment to meet ADR27B in '81. Heated rear screens standard on wagons, base sedan and panelvan had different grilles and round headlights. 'Gypsy' van had TD SL/E style alloy wheels and nylon plaid seat trim inserts; four spoke steering wheel and SL's headlight and grille. Power boosted brakes now on all models. Colour coded exterior mirrors fitted across the range except on panelvan and base sedan. Remote versions of the mirrors were also available. SL/X door trims went to top of the doors.

TF GEMINI: PRODUCED = March '82 - March '83
As for TE series Gemini
MODEL CODES = As for TE series Gemini including 8TV69 - SL/X Sedan / 8TV69 (opt. V6Q) - Star Sign Pack Sedan
ORIGINAL PRICES - Sedan = $7370 / SL/X Sedan = $8370

TF was a facelift version of the TE with interior and exterior upgrades.
SL/X had the most significant changes; grille and headlight arrangement resembled (VH) Commodore of the time. All other models had same grille and rectangular headlights as TE but now with vertical bars as well as horizontal. All sedan tail-lights were also reminiscent of VH Commodore. Side indicator lamps were deleted from front quarter panels. SL/X had wide side mouldings level with bumper height. Bumpers were a new one-piece black polypropylene moulding.

Interior received all new dash fascia and instruments; colour coordinated interior trim layout. Steering column and control stalks were shared with upcoming JB Camira. SL/X had quartz halogen headlights, new design centre console, coarse spoke design wheel covers, full instrumentation all in-dash. SL door trims now went to top of the door same as SL/X, window winder handles were plastic and colour coded, new dash fascia had four face level air-vents, all models had dual horns, wheel offset was 10mm further out making track 20mm wider front and rear. 'Gypsy' panelvan had same instruments and steering wheel as SL/X.

Petrol engines had mechanical fuel pump (All previous models had an in-tank electrical unit), belt driven air injection pump added to engine to reduce exhaust pollution without reducing performance.

Petrol engine manual 4 and 5 speed gearboxes gained revised wider spaced ratios.
A limited Edition shadow-toned SL/X called the 'Star-Sign' package was released early in '82. SL/X models had a model code of their own - no longer being just an SL with an option number.

TG GEMINI: PRODUCED = March '83 - April '85
As for TE and TF series Gemini
MODEL CODES = As for TF series Gemini including 8TV69 (opt. U4E) - ZZ/Z Sedan
ORIGINAL PRICES - Sedan = $7920 / SL/X Sedan = $9050

The new addition to the Gemini range was the ZZ/Z sedan; it was an SL/X level car with alloy wheels, front guard wind splitters, body-kit and other sports-type enhancements.

All cars received SL/X type seats, adjustable headrests, trimmed in vinyl or cloth to suit. SL's gained SL/X grille and headlight treatment. Wagon was now badged and equipped as an SL; all previous wagons had been trimmed above base level standard but below SL equipment level.

All models had a clock as standard although SL/X and ZZ/Z were digital. Heated rear screen now factory standard on all models.
Mechanically all models remained similar to the TF including the availability of the diesel engine.

RB GEMINI: PRODUCED = April '85 - Phased out in '87
POWER OUTPUT = Both unleaded and leaded versions = 52kw
COMPRESSION RATIO = Leaded - 9.6:1 / Unleaded - 9.0:1
TRANSMISSIONS = 5 Speed manual / 3 Speed Auto (optional)
DIFF/TRANSAXLE = 3.833 for manual / 3.526 for auto
MODEL CODES = 8RB69 - SL Sedan / 8RC69 - SL/X Sedan / 8RE69 - SL/E Sedan
ORIGINAL PRICES - SL/X = $11,050 / SL/E = $12,040
The replacement for the T series Gemini was the RB series, which was available only in front-wheel-drive as a four-door sedan. Most of Holdens competitors were offering hatchbacks; the RB was sold along side the LB Astra hatch to provide a wider choice of body styles. Engines for this series of Gemini were a new belt driven OHC 1.5L four cyl ISUZU coded 4XC1. This engine was more powerful than the TG 1.6L engine and had noticeably better fuel economy. The only engine upgrade saw a switch to an unleaded version to meet ADR's of '86.
No diesel engine was made available as an option. Late '85 saw the introduction of the Gemini Accents accessory appearance packages. Known as the 'Fashion' and the 'Action', they featured enhancements to the interior and exterior trim. The 'Action' received a rear boot spoiler and alloy wheels similar to the JB and JD SL/E Camira. Brakes were power assisted front discs and rear drums; SL/X had 13" X 5" steel wheels while SL/E had 14" X 5.5" alloys. Power steering was available on the SL/E. Interior componentry consisted of cloth trim, AM/FM stereo radio/cassette, digital clock and a split-fold rear seat, as well as retractable seat-belts front and rear.
SL/E had the following features over the SL/X.... Electric remote side mirrors, four speaker sound system (as opposed to two), tacho, tilt adjustable steering column, rear seat head rests, drivers seat adjustable lumbar support, body-coloured front and rear bumpers and grille, remote boot and fuel lid releases, overhead console with reading lights and 'Trip-meter' kilometre memory facility.

TECHNICAL INFORMATION : Gemini Model Features and ID