Nissan / Datsun S30 Buyers Guide
So you have decided you want to purchase an early Nissan S30 sports coupe. This is going to get complicated, well just a little bit, but hopefully after reading this you will know your Zcar and pick up a decent car and not some rust bucket that’s had 50+ owners.
Understanding the model range
Nissan sold their early cars in export markets under the name of Datsun, there are many opinions on the reason for this, but I won’t go into that here. Instead all you need to know for now is that your Datsun will have many parts on it that have the Nissan name. The most obvious is the L-series engine when you pop the hood that will say NISSAN OHC or Nissan 2400 (depending on the year of car).
Australian Market Cars
In Australia the S30 series was sold under two different variants. The Datsun 240z and Datsun 260z. They were sold from 1970 – 1977 and possibly into 1978 (maybe a month or 2). Over the years there were many subtle design changes that can make some cars quite unique. When looking for a Z its important to consider what you want from the ownership of your Z as to what year is best. Remember best is subjective.
Datsun 240z 1970 – 1973 – HS30
Despite what some people selling these cars will tell you, there is no 1969 Datsun 240z and no 1974 model. They were sold from 1970 – 1973 in Australia. The 240z was only available in 2 seater versions. All were fitted with an L24 engine from factory. For people looking for a collector car or investment in a Z-car the early 240z’s have always demanded the highest values. There are several reasons for this, but generally speaking its because of the early 240z’s rich racing history, their lighter weight (compared with later cars) and their relaxed emission standards that seemed to plague later cars. There is also some unique features and parts that separate the different years and this adds to their uniqueness.
The 1970-1971 1/2 – 1973 Datsun 240z Differences
So many cars have been modified and changed over the years with various parts it can often make identifying a car by year difficult. So what makes each model of 240z different?
When referring to early cars I’m actually talking about 1970 – 1971 1/2 cars. Later 240z’s are 1972 – 1973
Fibreglass headlight scoops – Yep the trademark looking sugar scoop headlights were actually made from fibreglass on the early Z’s. I’ve read various things that indicated tooling wasn’t available to make them from steel at the time, but whatever the reason the earliest cars had fibreglass headlight surrounds. By 1972 they were all steel.
Rear Hatch Vents – If you look at an early car you will notice that the rear hatch has vents in it. These vents are just below the hatch glass. Personally I love the look of the vents in the hatch. You’ll also notice that the inside of the hatch has a panel with holes in it to aid the venting in the rear hatch. I believe the vents were used for cabin pressure equalisation reasons.
Side emblems on C pillars – The C pillar area has a badge that instead of saying Datsun says “240z”. If you remove these badges there is no hole behind them like on later cars. This is where the hatch vents (were relocated to) were replaced. So 1/4 panels on the early cars were different because there was no hole behind the badge.
Badges – Early badges were also often made from steel, later cars had plastic instead. The steel ones are much better quality as the plastic ones have small pins on them for mounting them that have often broken over the years from becoming brittle. Of course the metal ones also weight a bit more, but its a small trade off for their higher quality construction.
Stowage bins – The early cars didn’t have any stowage bins behind the seats. The tool kit was located under the rear passenger and driver seat. Also the area behind the stowage seats had holes in it like swiss cheese. Presumably to lower the weight of the car while keeping structural integrity. Later cars had stowage bins behind the seats and tools were stored in here along with the wheel jack.
Non reclining seats – The early cars didn’t have recliner seats. Instead of a lever on the side they had a round knob that would allow minor adjustment. Later cars had recliner seats.
Dashboard – Early dashboards were slightly different in their design. A keen eye will be able to tell the difference, but they are quite subtle. The MPH speedometer starts from 20MPH not 0 like on later cars. The map light in the center console and heater controls were also slighty different (but this is from memory so might be wrong).
Centre console – The center console is different on the early 240z’s. It had the cigarette lighter above the fuse box and a twin (1 for choke, 1 for primitive cruise control throttle setup). The design of the console was also different to later cars. They are quite rare to find now and expensive.
Strut towers – The pattern found on the strut towers was also slightly different to later cars. The diamond pattern is hard to tell apart with different model 240z’s but generally speaking not many people notice the difference.
Body construction – I’ve read various information (unconfirmed for certain) that early 240z’s were lighter due to less safety standards in the metal used and things like side intrusion bars were not evident in doors. I’m not 100% certain but it is feasible that these cars are lighter than their later siblings because of a less sturdy chassis construction.
Fender mirrors – Many of the very early 240z’s that arrived in the country had fender mounter mirrors. I’ve seen 2 styles of these, the type that are a bullet (Japanese market style) mirror and a very rare (square type) fender mirror that was seen on the earliest 240z in the country HS30-0004. I’ve seen this car twice in person, truly lovely. I’ve also seen someone selling a single one of these mirrors once on ebay (they went for more than $250 AU for 1). I’ve asked various suppliers (Japanese and US) and finding a set is extremely difficult.
Valve Cover – Early 240z valve covers read Nissan 2400 and are getting quite rare now. 2400 represents of course the 2400 CC engine.
SU carbuerettors – The early SU carbs on the 240z had “3 screw” domes fitted. The difference was they had 3 screws holding the dome tops together instead of 4.
E31 / E88 Head – Early 240z’s also had E31 stamped onto the head. These heads were high compression and had a peanut style combustion chamber. Not so good for emisssion standards but high performance none-the-less. Later cars had E88 heads and in Australia these were still the good type of E88 closed chamber head.
Steering wheel – Early 240z steering wheels had no cutouts in their spokes. Instead they just had a recessed indent in them.
Engine Fan – Early cars also had a metal fan, later cars were replaced with a plastic fan. The heavier metal fan was known to cause issues and made a load of noise at the same time.
Brakes – Early disc brakes were slightly different in the HAT area. Not a huge issue but worth mentioning.
Hubcaps – Early hubcaps featured a D for Datsun in the centre piece of their overall design was different from the later ones. The later Z hubcaps wore the Z emblem in the middle.
Demister – I’m not sure if the demister was different in Australia or even available at the time. However US cars had a vertical demister glass in the rear hatch. I believe these are very hard to find now (even harder to find in working order).
Gearbox – First generation cars also had a different gearbox. The tail shaft flange was also different and the differential was mounted slightly differently, causing issues with diff wear that was later corrected in later models. The gearbox tunnel hole was also further forward than later models – something to be weary of if considering an engine / gearbox swap. Early gearbox’s had Porsche style syncro mesh. Later cars moved the trans tunnel gearbox hole further back and a different style of gearbox was fitted.
Indicators – 1973 saw the introduction of indicator repeaters on the bumper bars. Also below the bumper the parking lights were split to accommodate an additional amber lens.
Automatic – I’m also fairly certain that 1973 was the first year they produced an Automatic Z and Z owners have been converting them to manual ever since 
.
1974/75 260z and 1976 – 1977 260z – RS30
Like the 240z the earlier 260z series in Australia had subtle differences between the years. 1974 was the first year that the 2+2 was available. Starting with the 1974 model the main differences between the 1973 240z and the 260z were:
Tail lights – In 1974 the tailights change for the first time. The reverse lights are moved outside of the housing of the rear lights and chrome is more visually seen around the brake and amber turn signal. The rear tail light surround also changes to accommodate the new design.
Dashboard – The dashboard also has a new look compared with the earlier 240z. The gauges are less buried into the dash to improve visibility and the heater controls are also changed. Along with these changes the center console is also new.
Interior style – The seats and door cards also receive cosmetic changes to pattern and style. A new range of colours were also available and the passenger side also had a foot rest in the foot well.
Badges – The new name also meant new badges. The “Datsun” badges on the lower fender changed to read 260z with an orange Z. Although other badges were very similar to the 240z.
Aircon – Most 260z’s I’ve seen have been fitted with AC at some stage. This leads me to believe they were all sold with AC from the dealer.
Steering wheel – The steering wheel changed and was now not made from faux wood, but a rubber composition. The horn button also changed and was larger and more promient.
Carburetors – Possibly one of the biggest issues have with the different models is the type of carbs that were fitted to the later 260z. Known as the flat top carbs because their dome tops were, well flat. These carbs were design to meet stricter emission standards and as a result had additional plumbing and different intake manifolds and also air cleaner.
You will find many owners have changed these to different SU’s over the years. Be careful though since many come from British cars and may not have been the correct size to suit the engine.
Along with all the other changes there was a charcoal canister and other emission gear found in the engine bay. Usually this made the engine bay look more cluttered an less attractive than the earlier simpler and cleaner looking engine bay in the 240z’s.
Body styles – The 1974 body style was very much the same as the 73 240z style. So things like suspension struts are the same and radiator support areas.
Hatch – The rear hatch received 2 struts instead of the single 1 strut found in early cars.
Wheels – All Australian cars had 260z mag wheels fitted. These wheels are the same as the ones found on the American black pearl edition 280z. American’s go nuts for these wheels because they are quite rare, the Irony is that in Australian nobody usually wants them and finds them hard to move on ebay.
Engine – The 240z’s had an L24 engine in them. The 260z’s had an L26 a 2.6 litre engine. These now had a longer stroke to try and compensate for the emission gear on the engine. The engine block was still stamped P30 like the 240z but the E88 chamber was now of the “open” chamber design and lower compression. Compression was rumoured to drop to about 8:1 compared to the 240z 9:1.
Indicators – These were now found on the fenders to increase visibility.
Gauges – The gauges were now changed. The old 240z AMP gauge was replaced with the 260z volt gauge. The MPH speedo was changed to km/h in 74 and other gauges remained the same. The clock in all models was useless and in most cars has stopped working over the years or slowed down to count time in a less than accurate fashion. These can be fixed though, although its a common joke amongst Z owners the clock doesn’t work. Later 76 / 77 cars had different typefaces on the gauges.
Bumpers – On 1976 and onward cars the rear bumper had cutouts below the bumper. We assume this is because of the US 280z and its requirements for ridiculously large bumpers. Instead of Nissan making different body styles for different markets it appears they chose to just give everyone the same base chassis shell.
R200 Diff – The 260z was now fitted with an R200 stronger diff than the R180 found in the 240z. Ratio fitted will depend on how the car started life. Auto or manual.
Manual Gearbox – 260z 2 seater manual gearboxes were different ratio and are more sought after than other boxes due to their 2.9 first gear ratio.
The 260z 2+2 – GRS30
The 2 seater was sold in small numbers in Australia, in fact many people have stated that less 260z 2 seaters were available than 240z’s. Making them actually the rarest of the 2 seater. Many 2+2’s on the other hand were sold and infact the most common S30 series Z you will find in Australia is the 2+2.
2 extra seats – The most obvious difference between these and 2 seaters was the 2 additional seats. To accommodate the extra seats the roofline was modified and the whole was extended in length and width. Although the front of the 2+2 is the same from the front of the bonnet up until the windscreen, everything back was different. The doors were longer and the rear 1/4 window design changed.
The extra seats can actually be folded down to accommodate for a larger hatch area.
The rear hatch – was also different and the tail lights were the same, but the panel surround was actually slightly longer.
2+2 strut towers - were also different, so they often require different struts than the 2 seater.
Tool Stowage – The tool stowage area was now under the front of the rear seats.
Because of all these differences between the 2 seater and 2+2 many panels and other parts cannot be interchanged easily.
76-77 260z Changes
The 76-77 model had some small subtle changes.
Vented Bonnet – The bonnet on this model was now fluted and helped reduce vapor lock issues that earlier cars had (usually due to emission controlled carbs).
Dashboard Typeface – The dash now had slightly different typeface used on the gauges.
Hazards / Seats Belt Indicators – Many later models had these warning lights for when seat belts were not used and you now had hazard lights as standard. At least I believe so.
These differences listed are more than likely incomplete and there is likely to be many many more subtle differences between the models. This is just to give you a quick heads up when you first look at Zeds to know the most obvious changes so when you are looking at a car you will have a good idea of what is for sale. Corrections are more than welcome.
Common Problems
So now you know the differences what are the common problems when buying a Z?
Rust
Lets start with the most obvious problem rust! All Zeds were poorly rust proofed and even in sunny Australia they tend to rust over the years. Common rust areas are listed below. Although they can rust anywhere there is metal.
- Lower fenders – The front of the windscreen has a water tray drainage area that funnels down to the front guards. Unfortunately this area beomes clogged with leaves and other dirt over the years and if its remained clogged for a long time it will eventually lead to rust in the lower sections.
- The battery tray – From new most cars had a batter tray to catch battery acid. Unfortunately over the years these have been removed due to newer batteries being fitted. Over time battery acid leaks and causes paint to strip away from under the battery. This then exposes the area to rust. In the worst case scenarios the rust gets into the firewall and lower chassis rails. Inspect this area very carefully as damage here can cause the car to become very unsafe in an accident. Tap the area firmly and remove the battery to inspect for evidence of repair or damage in the past.
- Rear tire well – The rear tire well tends to accumulate water over the years from faulty hatch seals and as a result it rusts out. Although easily repaired, you may need to remove the fuel tank before welding this area for safety reasons.
- Fuel filler – The area below the fuel filler tends to attract moisture and you will often see rust below this area on a Z. Again difficult to weld without blowing yourself up by igniting fuel. So again you must remove the fuel tank.
- Chassis rails – These are often beaten up and damaged over the years from speed humps and other stupid driving from previous owners. Get a car up on a hoist and inspect carefully – very carefully.
- Lower sills – The sills on Z’s tend to be victim to rust, but it can often be hiding behind the paint on the outside. The rear wheel, or just in front of the rear wheel is a very common spot to see them rust out.
- Hatch – The hatch often has rust around the lower section where the latch is located. The panel here often rusts from underneath so check for evidence of rust above, usually underneath is much worse.
- Floor pans – These in my experience haven’t been too bad on most Z’s, but check these for holes in the floor, look under those carpets.
- Doors – The doors, especially lower sections often rust and are difficult to replace or repair (read expensive). Many owners have bogged them up over the years so be vigilant when inspecting these areas.
- Bonnet – The front of the bonnet often starts to bubble and rust – although the upper region usually appears to be ok.
These are the most common areas, but depending on how the car has lived for the past 30+ years will determine where rust is hiding. Avoid cars that have been bogged up and received more than a couple of coats of paint over the years as these will be hiding problems such as bogged up areas and potentially accident damage, which brings up to the next common issue.
Damage
Since the Z was a cheap sports car in the day and many have changed hands over the years. Its not uncommon that many of them have received more hits than Elvis. Small accident repairs are ok, but major damage repairs can be very expensive to fix. A Z that has been smacked hard in the side will often destroy the roof line and cause poor alignment.
- Front end damage – Should be obvious by looking at front panel alignment. That is the bonnet, and fenders. If there is an uneven alignment between the panels it could be just poor alignment or indicate a more serious issue of previous damage.
- Check the radiator support area and see if the metal is creased. If it has been creased and looks uneven its probably due to an accident at the front end at some stage.
- If doors poorly align again this could be due to cheaper replacement doors such as those from Taiwan or poor repairs.
- Lift the carpet in the rear hatch area. Check the floor pan, is there creases in the metal here? You might want to get under the rear of the car and check if the 1/4 panels are nice and neat. If there area creased or bent its probably been hit in the rear at some stage. Likewise if the hatch doesn’t shut nicely this could be another indicator of damage.
- Engine bay area – Look at the chassis rails in the engine bay. They should be nice and straight. If not the car may have had a serious front end impact.
