Notes on Valuation

Valuation of early 911s

People ask me for valuations of 911s all the time. My method is simple. There are two aspects: intrinsic and extrinsic.

Let’s start with intrinsic values

At the moment, coupes are more valuable than Targas. I know there are Targa lovers, and I understand the appeal of an open car. The Porsche solution to opening the car was genius, using a collapsible/removable center roof section that can be stored in the car. Safety is preserved with a bar providing rollover protection, and the massive, wraparound rear window affords excellent rearward visibility. For versatility, the Targa may lead on intrinsic value for many people. For others, the superior chassis rigidity, quietness and foul weather protection of the coupe is more attractive. These are not matters for debate. They are subjective.
What is not subjective is the timeless design and simplicity of the 911 – especially those pre-74. It’s iconic and it pleases the eye today as it did in the 60s.
There are only two “inherently balanced” 4-stroke engine configurations commonly in use. They are the inline 6 and the horizontally opposed (boxer) six. The 911’s boxer configuration means the engine can run butter smooth from a few hundred RPM to around 6500 – a couple thousand more if the crankshaft is counterweighted. Induction systems in these cars are of 3 types: carburetors, mechanical fuel injection and electronic fuel injection. All of these types can be made to start and run smoothly and reliably. All have mechanical distributors. The engine top end configuration is single “overhead” cam with hemispherical combustion chambers. Open the engine lid and all 911 engines (and 912s) have induction at the top, exhaust at the bottom. Highly logical. There is a wonderful symphony of mechanical sounds emanating from a 911 engine that is distinct from other engines. Transmissions are manual 4 or 5-speeds plus the semi-automatic Sportomatic, starting in 1968.
Generally, a maintained 911 will start quickly and run in most any condition, demanding little of the driver but returning tactile pleasure and responsiveness so seductive the people with multiple cars will often grab the 911 keys for errands around town as well as weekend drives.
This basic, obvious laundry list of virtues is partially shared by a few other vintage sports cars, but none quite to the degree of 911s (I know, I’ve tried a lot of others and come back to the 911).

The inherent balance contributes to longevity, as the ‘bottom end’ of an early 911 engine can go 100-300K miles without need for rebuilding. “Top end” rebuilding can be necessary at 80-150K intervals. Rings and valve guides are the cause of the smoking which precipitates the need for top end overhauls. Note that improved valve guide materials extend the life of the overhaul and excessive fuel (more often from MFI systems) accelerate ring wear. Another reason to keep the early 911 in top tune.

As an aside, the phenomenon of a puff of smoke on startup is a “feature” of a horizontally-opposed engine. It does not mean time for major work in most cases.

So, from an intrinsic standpoint, the early 911 has value today – irrespective of the market – as a reliable and enjoyable car to drive. The fact is, bubble or not; depreciation or appreciation, it’s capable of putting a smile on your face like few equivalently priced “modern” cars.

Another sidebar:

For decades, non-sunroof coupes were more desirable among 911 enthusiasts than sunroof coupes. For decades, I’ve been buying the latter, starting with my 66 911 in 1974. There is a sub-segment of the owner population that prefers the sunroof cars, while another contingent sees them as something to be removed if they like the car in every other way. I usually resist predicting market trends, but I do feel sunroof cars will rise in market value because of the ‘retro’ feel of the open roof. Intrinsically, the minor complaint of early 911 owners is lack of air flow through the cabin. The sunroof is a partial solution. For those 6′ 2″ and taller, the conceptual appeal of a sunroof may be moot, as it costs about an inch of headroom.

Evaluating intrinsics

First, the chassis of the 911 is all relatively thin sheet metal, cunningly folded and welded to produce a [for its time] stiff chassis. This chassis stiffness deteriorates with hard use, and 40 year old 911s of the same type will demonstrate very different chassis dynamics depending on their history. Put properly on a shop lift, some 911s – both coupes and Targas – will flex to the point the doors will not open or the gaps will double in size at the rear top of the door. As alarming as this appears, it is normal. Nevertheless, it’s good to check, as the more rigid the chassis, the more satisfactory the car will feel on twisty roads.
With the car on the lift, you have an expanse of sheet metal to look over. Start with the front pan – the area in front of the gas tank. 911s carry their battery (2 in the 69-73 cars) up there. The original lead acid batteries were vented, but any moisture accumulating on top of the battery became acidified and that acidic water went to the ‘dished’ area forward of the gas tank. Some likely stayed under the battery as well, especially in cars routinely parked on a slanted floor. The front pan is a single panel of sheet metal, so once corrosion starts, it penetrates to the outside of the car. Porsche provided drain holes with little rubber tube to extract liquids, but despite this accommodation, the majority of early 911s need to – or have had – front pans replaced. The point here is that if you find an original, undisturbed front pan, that is a bump in value. A significant one. I’d put it at $3-4000, as replacing the pan (Restoration Design makes a good replacement stamping) to a high professional standard will cost about that much. You may find an obviously replaced front pan with bubble gum welds, visible seams and often, misalignment. Same deal. Needs to be redone at some point, so $3-4000 cost.

Walking rearward, you should see a protection plate behind the gas tank, with a seal on the forward edge. This plate is often beat up or missing. If it’s nice and straight, that’s +$500, IMO, because it implies the owner(s) have not let random garage monkeys blindly throw floor jacks under the car or lose parts when working on it.

On to the main passenger pan – it has a couple vulnerable areas. First is the lowered area below the gas/brake/clutch pedals. Water intrusion to the interior can result in pooling there. Unlike the acidified water in the front compartment (trendy now to call it the ‘frunk’), the water inside the car tends to be cleaner and takes far longer to corrode sheet metal. Interior sound deadening is a tar-like coating that protects the inward side of the pan for decades. The other place water tends to accumulate inside is in the back corners of the passenger floor pan. A clean main pan, with no evidence of corrosion from the inside, and with undercoating intact, and without the denting from random floor jacks is +$20,000. Yes. Big number. But it’s like looking at the foundation of a house. Whatever condition the rest of the car is now, it can be made excellent if the lower chassis is square, straight and clean.
The rocker panels on 911s are designed for minimal complexity and for a 70s European reality where owners personally washed their cars weekly. Absent that care, the thrown mud, leaves and road debris kicked up by normal driving probably accumulated at the rear of the front wheelwells and the front of the rear wheelwells – directly against the front and rear of the longitudinal. Look at the area inside the lower rear of the front fenders and the area in front of the torsion bar access hole (the other side of the base of the door striker panel). These are the most common places for dirt to hold moisture in long term contact with the sheet metal – leading to penetration into the rocker panels – the outer skin. Rocker rust isn’t always easy to find, as an S-trimmed stock 911 will have rocker panel trim covering the outer portion. It will also have a metal threshold plate. In a typical appraisal situation, you cannot see under these trim pieces. You have to go on visible indicators. Cars with removed rocker trim or rubber threshold trim are easier to assess, as they have a narrow outside strip and a rubber threshold plate you can usually – with seller’s permission, of course – pull up at the rear. You should also look carefully at the inner joint between the striker panel and the inner structure behind the door. If the seals can be removed to examine that area, look for bubbling. Apparently un-rusted rockers/longitudinals are +$1000. Not more, because it is common to find concealed rust, especially under the outer trim.

Worth mentioning is the ‘dogleg’ portion of the front fenders. This area in front of the front door opening has a channel stamped inside the fender to guide rain & moisture down and out. The opening at the bottom can easily become blocked and a decade of moisture there will cause rust to bubble out – sometimes behind rocker trim. This can be fixed with patch panels, but if the fenders show no corrosion here, it’s a +$2000 adder.
Moving back, there is a complex area below the rear torsion bar mount that can become corroded. I call this area “complex” because several panels of sheet metal come together there to support the weight of the rear of the car. Its structural importance cannot be overstated. Penetration of rust in this area must be addressed by a highly experienced Porsche repair shop. Note the lower flange in this area is often dented and bent from un-knowledgeable mechanics using it as a jacking point. I like to see this area clean and undisturbed.

Moving to the mechanical… these cars have heat exchangers to provide cabin heat using the outside of the header pipes. The ‘cans’ around the heat exchangers are vulnerable to road damage and rust. Unmarked (or replaced) heat exchangers are a significant value-add for 3 reasons. One, replacements are expensive, two, it’s common that one or more exhaust studs on the heads will snap when you remove the exchangers, adding cost if you replace, and three, it is another indication of the kind of ‘life’ lead by the car. In-place, undamaged; un-corroded original heat exchangers are +$2500 in the car’s value.
Oil leaks come in several flavors. There is ‘weeping,’ which is accumulation of oil in small quantities on surfaces like the case, oil return tubes and heat exchangers. Weeping oil leaves a drip a few times a year, but also makes the car give off a hot oil smell when driven to full temperature. Tolerable, but not ideal. Actual drips – like one per month or more – can be expensive to source and stop. People will tell you there is no such thing as a ‘dry’ early 911 engine. That is incorrect. A dry early 911 engine is a +$3-4000 value bump.
With the car on the ground (and maybe this is where you started), look for bubbles in the paint around the base of the front fenders where I mentioned – just above the rocker trim. Look along the seam at the top between the fender and cowl and at the base of the A-pillar. Check along the edge of the windshield seal, around the headlights, on the hood (especially underneath the front edge where the outer skin folds over). While the hood is open, check the channel where the seal sits on the body at the rear of the frunk. Be sure to check the lower portion of each door, including from underneath (look at the seam where the outer skin folds over), at the base of the Targa band or at the rear corners of the rear window of a coupe, and under the engine lid at the rear edge. Bubbles in any of these places can mean not only a specialist repair but also a paint job. Undisturbed metal in all those places = +$12,000. It’s a big number because these spots are the ‘canary in the coal mine’ for rust that is about to blossom elsewhere on the car.

So let’s talk extrinsics

Somehow the hipsters have discovered early 911s. And the collectors. And the second/third generation of those professionals who comprised the initial wave of 911 buyers in the late 60s/early 70s. They were disproportionately engineers, physicians, pilots; lovers of machinery – and perhaps more important, iconoclasts.
Porsches have never represented much of the volume of yearly automobile sales. Here in the US, I figure 0.025% max before the model proliferation began in 1997.
So Porsches, especially 911s, were special when new, and even though the market devalued some of them down into 4-figure territory in the 90s, they have always had a core of dedicated buyers/owners.
In the bad old days, early 911s were sometimes modified to look like newer 911s, with varying amounts of money spent to “upgrade.” Today we know that every penny of that money negatively impacted the value of the car by as much as 300%. There is a whole mini-industry dedicated to reversing these upgrades. But upgrades can be beyond tackling still, on some cars. Most difficult to deal with are rear flares, especially Turbo flares, which require the replacement of most, if not all of the rear quarter panels, and the ‘short hood’ conversion, which, if done with a later front bulkhead or even a clip from a later car, will cost many thousands to put right.
Both of these ‘upgrade reversals’ will require significant or complete repainting. To calculate the impact on value of ‘upgrades,’ you have to deduct not only the cost of doing it right but some additional penalty for the time you do not have the use of the car. The best shops for this work may have a backlog as much as 1-3 years(!).

Let’s just focus for now on the more-or-less stock-appearing 911s.

The Hagerty Valuation Tool is a good place to start. They will break out value ranges in broad strokes – coupe, Targa, “Normale,” T, L, E and S. They don’t deal with color (see my blog of 7/7/16) or manual vs. Sportomatic, or numbers-matching vs. not, or modifications. They have no way of factoring the value of ‘seat-of-the-pants’ dynamics of a car’s performance.
And neither can I in a general guide like this. I can evaluate cars in person. This guide is to empower you to come close on your own.
First, if you are looking to spend what it takes to have a collectible car, you likely have advisors already. And they’ve told you to find a 73 RS or pristine 72/73 S coupe. And that’s good advice.
If you are not a collector with $300-900K to spend, you should know there’s a lot of similar experiences across the range of T, L, E and earlier/later S models. All share basically the same stampings as the RS. All have more or less the same interior, trim, transmissions, exhausts; perhaps wheels. The Porsche option sheets allowed the lowliest 911 to have S brakes, S sway bars, S trim, S gauges and the (now ridiculously-valuable) sport seats. Full leather interiors were offered across the range, as were Fuchs, sunroofs, power windows, and a bunch of other options. For this reason, I resist calling 911s a “market.” They comprise a collection of individually-considered cars in a wide valuation range.
Extrinsically, the investment buyers are looking for prestige and limited numbers. Although 1590 Carrera RS 2.7s were made, they are the value pinnacle of mass-produced 911s. In the same chassis number range, the Factory made RSRs which are beyond… up to 2X the value. Buyers of these cars have paid advisors.
So I’m primarily advising here on the more common production configurations. If a minimally-optioned but original 911 T is priced at, say $60,000, a similar E is going to be $90,000 and a similar S is going to be $140,000. This is about where the coupe mean pricing is at the moment. NOTE: this is only rough rule of thumb intended to outline the comparative market values of the T. E and S. In 1965-66, there was only a ‘911′ – sometimes referred to as a Normale.’ Relative to the later T, E and S, they tend to fall between the E and S, with progressively earlier chassis numbers worth the most (I’m excluding the 232+ 1964-built cars, which are in a price segment all their own).

The total valuation

The intrinsic values and extrinsic values have a relationship, but they don’t simply add up in a 1+1=2 manner. The intrinsic valuation process I went through above adds up to $47,000 if everything is in pristine shape. On a 65/66 911, the intrinsics should be a 140% multiplier. In other words, a $90,000 66 911 with all the “goodness” listed in the Intrinsic evaluation is $126,000 as a median valuation.
I’d put a 67/68 911 intrinsic multiplier at 1.35, a 68 911 L or S multiplier at 1.75, a 69/70/71 T multiplier at 1.5, a 69/70/71 E multiplier at 1.75, a 69/70/71 S multiplier at 2.

The 72 and 73 cars are valued a bit higher as ‘last of type.’ and of course because of the oil tank placement of the 72. Multipliers would be 1.6 for T, 1.8 for E and 2.2 for S.
Again, this is a guide and there is a constellation of factors that tug pricing one way or another from these center points.
For a precise evaluation, I need to see and drive the car. For a tighter evaluation I need to see photos. But hopefully, this guide gives you a starting point.

And yes, I look at 74 and later 911s, which have most of the same considerations, but its starting to feel like I’m writing a book, so will get to those cars later.