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Price opinion from advertisements and recorded sales. Not an inspection or a certified valuation.
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Reference photograph of a Porsche 911 SC
Valuation · Porsche · G-series · 1978-83

Porsche 911 SC

3.0L NA air-cooled flat six · 150 kW / 265 Nm · 5sp manual · RWD
AVOIDRated within the over $100k band · 101 of 104 at this money
Model value
$107,500
Must gain each year to break even
+8.5%
The projection does not clear it, and nor does most of the library.
CarQuant score
49/100
Scored against the over $100k band, not the whole library
Evidence grade
Thin
One to three recorded Australian sales
$107,500
$67,147 lowhigh $119,200
Calibrated to a thin record
One publishable Australian result, an $80,000 former left-hand-drive Cabriolet at Shannons in November 2020. The other Shannons entry is a pre-sale estimate whose hammer price was never published.
Measured across this library, a value resting on a single Australian result runs high about six times in ten, by a median of five per cent.

Looking at a 911 for sale?

Put in the asking price and the odometer reading. You will see what this model should make at that reading.

Should make, typical example
$107,500
At about 55,000 km. Enter an asking price to compare.

Odometer only. Colour, options, history, condition and the photographs move it further, and that is what the report reads.

A person reads the advertisement and its photographs. Usually back within 48 hours. Read a real listing report

Price history

Today $107,500 · modelled median at five years $97,338
Solid line: the value this library has carriedDashed from 2026: modelled · even money $81,458 to $108,837
The green band is the even-money range and the one to plan on: half of outcomes land inside it. The pale band behind it bounds eight in ten ($67,147 to $119,200). The path is this model's own: it starts along the momentum of its recorded history and bends toward its projected median as the horizon lengthens, so no two cars share a future curve.

The verdict

The numbers argue against it. Scores 49/100, ranking 101 of 104 in the over $100k band. Liquidity is the strongest input, risk resilience the weakest.
Running it costs about $9,110 a year (8.5% of value), which is what the economics score measures. All in, including the projected value change, it is $12,562 a year.
The model's five year median is $97,338, a -9.5% move, with the tenth percentile at $67,147.
Value calibrated to a thin record. Treat the level as provisional.
Evidence
Thin1 recorded sale
Off its peak
-17%
Value band
moderate
At least one recorded transaction plus a source. Direction is sound, the exact level less so.
Scored against every recent Australian sale this library holds, half its values land within 11.2 per cent of the price paid and the rest miss by more, in either direction. Projections are therefore damped toward flat in proportion to how little is known, and the plausible band is never narrower than the error the model is known to make.
Short term (1-5 years)$12,562 a year all in, -9.5% median value move
Long term (10-15 years)Scarcity case already formed
Negotiate from$107,500

Recorded sales

Every recorded observation, and when
2 rows on record
$136k$105k$73k
202120222023202420252026
the value this record published, year by yearnow $108ksolddid not sell
Every row, with its price and note (2) ↓
Aug 2023Shannons$75,000Not a sale
NOT A SALE - pre-sale estimate only. 1983 SC 3.0 Coupe, Shannons Timed Online 15-22 Aug 2023, published estimate A$65,000-A$85,000 (midpoint shown here), 394,806km, single owner 36 years, Guards Red repaint 2010. The sold price was never published.
Nov 2020Shannons$80,000Sold
SOLD. 1983 911 SC Cabriolet, Shannons Spring Online Auction closed 18 Nov 2020, explicitly described as a former left-hand-drive car.
1 completed Australian sale of 2 rows. Rows marked asking, no sale, or context are shown for honesty but do not count toward the evidence grade: an ask is not a transaction, a pass-in is a refusal, and a provenance or overseas result does not price the ordinary local car. The badge on every row is computed by the same rule as the grade, so the two cannot drift apart.

Score breakdown

Against the over $100k band median
104 cars in band · ink tick marks the median
Ownership economics30% of total
63/100-6
Scarcity25% of total
50/100-15
Demand durability20% of total
38/100-40
Liquidity15% of total
64/100+32
Risk resilience10% of total
7/100-27
Sub-scores run 0-100 before weighting; the weighted total is 49/100. Medians are computed live from the 104 cars currently in the over $100k band, so this picture moves when the library does.
The working behind each factor: baseline and drivers ↓
Ownership economics30% weight
63/100
Baseline84 pts
− 8.5% of value a year to run-21 pts
Sub-score (baseline plus drivers, clamped 0-100)63 pts
Scarcity25% weight
50/100
Baseline20 pts
+ 900 survivors estimated in Australia+30 pts
Sub-score (baseline plus drivers, clamped 0-100)50 pts
Demand durability20% weight
38/100
Baseline48 pts
+ The cheapest way into the right air-cooled 911 shape+10 pts
− Half to two-thirds of the local pool is imported or converted-14 pts
− The last G-body to re-rate and the first to soften-6 pts
Sub-score (baseline plus drivers, clamped 0-100)38 pts
Liquidity15% weight
64/100
Baseline12 pts
+ 60 days on market+35 pts
+ 70 sales a year+17 pts
Sub-score (baseline plus drivers, clamped 0-100)64 pts
Risk resilience10% weight
7/100
Baseline46 pts
− Rust repair and a bare-metal respray runs to $35,000-14 pts
− Head-stud pull on 1978-79 cars is a $16,000 engine-out job-10 pts
− The one publishable local result was a converted car-8 pts
− Thin transaction record-7 pts
Sub-score (baseline plus drivers, clamped 0-100)7 pts
Model output, not advice or a valuation. Verify independently before acting.

What it costs to own · about 2,500 km a year

Annual cost of access, excl. fuel
$9,110a year
Share of value per year
8.5%
Scheduled servicing$2,05023%
Tyres, annualised$1,40015%
Registration and CTP$1,09012%
Insurance$2,60029%
Sinking fund (failure table)$1,97022%
All-in annualised (a different number)
Purchase (model value plus duty)$111,800
Running costs × 5 years$45,550
Median exit, net of selling cost$94,538
All-in annualised over 5 years$12,562/yr
Share of value per year11.7%
Cost of access is what the car costs to run. All-in annualised adds depreciation, duty and selling costs across a five year hold. They answer different questions and are labelled separately for that reason.
Break-even appreciation, 5 year hold
8.5%a year, only to get the money back
This library projects
-2.0%a year
The projection falls 10.5 points a year short of the hurdle. On these assumptions this car is a cost, not an asset, which can be an entirely rational thing to buy but should be bought knowing it.
Purchase$107,500
Stamp duty$4,300
Running costs x 5 years$45,550
Selling cost at exit, 2.6% of the salescales with price
Sale price needed at +5 years$161,558
Storage
Bought at
No forecast is used to compute the hurdle. It is the purchase, the duty, any premium and 5 years of running cost, grossed up for the cost of selling and spread back over the hold. The projection it is measured against is the weakest number in this product and is drawn that way in the chart above. Transport, finance and any restoration spend sit outside it.

Specification

Engine3.0L NA air-cooled flat six
Power / torque150 kW / 265 Nm
0-100 km/h6.3 s
Transmission5sp manual
DriveRWD
Kerb weight1,160 kg
Built worldwide60,265
Delivered to Australia475
Effective AU survivors900
Australian sales / year70
Typical days on market60 days
Launch priceNot established

What moves the price on this model

Colour hierarchy
Original paint in a factory colour+8%
One documented repaint in the original colour+2%
Former left-hand-drive car resprayed at conversion-12%
Options
Australian delivery with matching numbers+30%
Original specification rather than a backdate+15%
Chain tensioner retrofit and 915 synchros already done+8%
Odometer sensitivity±1.8% per 10,000 km vs 55,000 km
Applied on top of these

Condition, history, originality, ownership, delivery and modification multipliers apply to every car in the library. They are applied automatically when an advertisement is analysed, and the schedule is set out once, on the analyser page.

Projected value in five years

Projected value at five years
$97,338
-9.5% on today
The model's figure. Today it is $107,500.
Even odds it lands between $81,458 and $108,837.
$67,147 lowhigh $119,200
The shaded range is even money and 34% wide; the outer figures bound eight outcomes in ten. Band width follows the evidence - a model with a tight measured record carries a tight band.
A weaker five year outlook than 82% of the library.
-26.6% weakest projected move in the librarystrongest +73.1%
Five-year cost of ownership
Value change alone: -$10,162 across five years.
Running costs over the same period: $45,550.
Duty and expected selling costs: $7,100.
Net cost of five years of ownership: $62,810, or $12,562 a year.
The projected value fall is added to the running cost. Depreciation is the larger number here.

The case for and against

The case for

The Australian pool is deep enough to actually shop in, and the spread from $57,500 for a rough car to $187,500 for the best leaves plenty of room between the two ends. Hamilton-delivered cars, an estimated 350 to 600 across six years, are the scarce half of a common model.

The case against

An estimated 50 to 65 per cent of Australian SCs are imports or former left-hand-drive conversions, the highest proportion of any car in this tranche, and that supply is holding the middle of the market down. Values have been flat since 2023 and the only published local result is an $80,000 converted Cabriolet from November 2020.

Known faults and risks

Risk 1An estimated 50 to 65 per cent of the local pool is imported or ex-left-hand drive
Risk 2Head-stud pull on 1978 and 1979 cars, corrected engine out
Risk 3A backdated car is worth what the backdate cost, not more
Rust repair and bare-metal respray - imports may hide UK-market corrosion$35,000
Head-stud pull on 1978-79 cars, corrected engine-out$16,000
Type 915 gearbox synchro rebuild$6,500
Clutch replacement, engine-out job$4,500
CIS fuel distributor$2,650
Chain tensioner retrofit - assume it is undone until proven$2,150

Similar cars, and what they cost to run

Evidence behind this valueThin · 1 recorded sale
Carried value
$107,500
Historical price
2016 · $109,6002026 · $107,500
Thin
At least one recorded transaction plus a source. Direction is sound, the exact level less so.
The one Australian result is not the car this record describes

Shannons sold a 1983 SC Cabriolet for $80,000 in its Spring Online auction closing 18 November 2020, and the catalogue described it explicitly as a former left-hand-drive car. This record is a coupe in original right-hand drive. Both of those differences point the same way, and the result is carried as a floor rather than a comparable.

Read the rest of the evidence notes (3 more)
The second Shannons entry is an estimate, not a sale

A 1983 SC 3.0 coupe ran in the timed online auction of 15 to 22 August 2023 with a published estimate of $65,000 to $85,000 - 394,806km, one owner for thirty-six years, a Guards Red repaint in 2010. The hammer price was never published, and once Shannons left the auction business that November the archive was stripped, so it never will be. The $75,000 that circulates against this model is the midpoint of an estimate wearing the clothes of a result, and it is not used here.

Provenance sets the price, not condition

An estimated 50 to 65 per cent of Australian SCs are imports or former left-hand-drive conversions, more than any other car in this tranche, and that oversupply holds the middle down while an Australian-delivered matching-numbers car carries 25 to 35 per cent more. A backdated SC is worth what the backdate cost and not a dollar beyond it.

The value is research

Confidence on the figures is low, and this page grades it that way rather than dressing one estimate and one converted car as a series.

This page prices the model.
The report prices the car in the advertisement.

Send the link. A person reads the advertisement and its photographs and sends back what that Porsche 911 SC is worth, what to offer and when to walk away, with five years of costs at the distance you drive.

Read a real listing report

The evidence on this model is thin and the report says so on its cover. Read a complete one on a real car first. Seventeen sections, no account, nothing to pay.

This model, today$107,500
Half of sales are further out than$12,017
The report$249
48×
the price of the report: what half of real sales of this model sit further from this page's number than, on this car
Watch this model
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One line of email when this desk publishes a call on a Porsche 911 SC, or records a new Australian sale of one. Nothing else, no schedule, and on a quiet model you may hear nothing for months, which is itself worth knowing about a car you are chasing.

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