1/8 Porsche 936-78

[ScratchBuilt]

Time to start a new build-thread! I’ve mentioned a few times in other posts that I’ve always thought the Porsche 936 doesn’t receive the plaudits it deserves, and it’s a project that I’ve wanted to find out more about. Certainly, in the last twenty-odd years there’s been plenty of books produced about the 917 (and a few new ones about the 956/962), but for the 936 there’s really only been the Jurgen Barth / Bernd Dobronz ‘Porsche 936’ that really gets into the detail of the story...in German.

Why the lack of love for the 936? I suspect it’s mainly just the time it happened – sportscar racing was arguably not it a strong state of health in the mid to late 70’s, and 1976 was the only year it raced as part of a full championship season; after that it was basically Le Mans as the priority. However, it was certainly a successful car: three official works chassis produced (plus an unofficial fourth), raced at Le Mans over a six-year period - 1976 to 1981 – resulting in three wins, two seconds and a third.

Of the three official factory cars, chassis numbers 001, 002 and 003, it is perhaps 001 that has the most history; it was the only works 936 to run at all five of the LM24’s contested by the factory. It first appeared at the Nurburgring in 1976 in the black Martini livery, before changing to the more familiar white for Le Mans. For 1977 the 936 was updated with revised bodywork and suspension geometry, and 001 recorded it’s famous 24-Heures win completing the last two laps on five cylinders. 1978 was a big update – revised bodywork again, but also the new version of the turbo flat-6 engine with water-cooled heads (similar to the one found in the Moby Dick). Chassis 001 would finish second at Le Mans in 1978, retired in 1979, and recorded a twelfth-place finish in 1981.

1/18 scale die-casts:



Until a few years ago, chassis 001 was still in the water-cooled 1978-81 configuration, but has been restored to 1977-spec. It’s my understanding that this is the only 936 in private ownership. It appears that 002 and 003 are still owned by Porsche – 002 is also in 1977-spec, and 003 is still in it’s winning ‘Jules’ livery from 1981. I will be basing my build on chassis 001, in 1978-spec – it’ll be a great companion for my 1/8 Moby Dick model, I think the long-tail bodywork looks fantastic, and you can’t go wrong with a Martini livery!

Chassis 002 in 77-spec on display at Le Mans 2014:



Chassis 003 in 81-spec on display at Le Mans 2023:



Chassis 001 (note aero wheel discs, positioning of driver names, and shape of nose-panel behind the radiator) in 77-spec, also on display at Le Mans 2023, with Moby Dick lurking behind:



I actually started this build in late 2018! The 935-78 was in the final stages, and I had decided that the next project would be a 956. However, the opportunity presented itself to get some first-hand reference material on the 936, and for a while I was considering trying to build the 956 and 936 side-by-side. Before starting the 956 properly I constructed the basic core of the 936 chassis frame:



As before, it’s a mix of 3.2mm and 4.0mm styrene and some aluminium tubing, with joints pinned and reinforced as much as possible. The main cockpit and footwell structure is very similar to the 917 and 908-03 layout – the 936 project used a lot of know-how from the older cars, and would draw many parts from the ‘archive’ – gearbox and uprights from the 917, for example. I used my trusty Lego to create jigs and fixtures to hold the tubes, keeping everything square and true.

When I started the 956 in January 2019 one of the first things to be built was the engine block, as I needed this early-on to work out a way of mounting the drivetrain solidly to the tub. If I was making one engine block it made sense to make a second, so this will now be used for the 936! I also made a second fibreglass fan-shroud a bit later, so this will also now see service:



Although the original 936 build was put on hold for a few years, I’ve continued to gather reference photos, etc, and was finally in position to make a (re)start in late summer. The 936 carries it’s fuel in two tanks, one at the back of the cockpit, the other in the right-hand sill, and I knew I could use these structures to add some strength to the tube-frame. So, my first job with the chassis was to add the outrigger frames and work out a plan for the fuel tanks:



The cockpit tank is relatively conventional, so this was the starting point. I added some extra box-section into the back of the frame to give the tank something to sit on:



The tank itself is a styrene outer skin over a fibreglass core, with box-section internal reinforcement:





The right-hand end of the tank incorporates a tunnel to allow the gearlinkage and cabling to pass through, so I’ve made this a separate section which will fit in once the main tank is in place. This piece has to fit around some of the chassis tubes too, so I’m having to think ahead!

The tank in the sill forms the inner panelling for the cockpit, and has some pressed detailing for stiffening. This is visible, so I made the panel as two layers of styrene (one with the X cut-outs, one plain) and a fibreglass backing:





I’m still working out how I’ll do the rest of the sill tank, so I’ll return to that later!

The front engine mounting in the 936 is a relatively simple V-shaped frame which picks up on the same mountings as the front frame on the 956. There will be a small bracket on the chassis at the bottom, and two horizontal pins further up. Given that I had the engine block already, it was a good time to make a start on the V-frame:



I’m leaving the lower mounting for a while, as I’m going to concentrate on the cockpit section for now. The exact height of the drivetrain within the chassis is currently ‘to be confirmed’!

That’s all for this initial post. I’ve got several more weeks of work to show before I get up to date – I’ve been doing a little more fibreglassing, some more chassis tubes added, and getting the pedals underway, for example. I’ve also got another repair-job to do on a ‘MMC Models’ Formula Ford model, so I’ll probably post a mini-thread on that at some point (similar to the Chevron B34).

As always, I’ll try to find some new ways of tackling familiar jobs. I don’t know if I can improve on the level of detailing used on the 935 and 956, but it will certainly be good to see those details on a tube-frame car like my early 917 and 908-03 models. I wouldn’t want to build another 917 or 908, but the 936 is different enough to keep me interested. The doors will still be a pain, though, but life can’t always be easy, can it?!

Hope you like it, and thanks for reading.

SB

[Deathtrap]

Ow yes!!! Another cool project.
I'll surely be following this one.

Thx for the short introduction of the car. I didn't know too much about it.
Good luck with the build.

[ScratchBuilt]

Hello again - another catch-up with recent progress.

I decided not to extend the chassis into the engine bay for now – there’s plenty to keep me busy in the cockpit, and it’ll all be much easier to do without worrying about another 12” of structure hanging off the back! So, the next job was to create the two long chassis tubes that define the upper edge of the cockpit running down to the nose. In profile they’re simply a straight tube with a curved end, but the curved end is actually kinked to one side to (eventually) make room for ducting. They’re made from 1/8” styrene tube, wire-reinforced, with the curved section built-up from smaller sections and some filler. I fitted the left-hand side first as I wanted better access to the other side for the pedal-box work:





By this point I’d also spent some time adding Greenstuff to most of the existing chassis tube joints. In true 1970’s Porsche fashion the ‘welds’ are not intended to be pristine – ‘functional’, rather than ‘things of beaury’!

The main structure of the pedal box is a channel section that mounts the two master cylinders, and the base for the brake pedal:



The clutch pedal has an extra support bracket but the throttle pedal appears to be cantilevered from the brake pedal mounting. I don’t remember the 917 or 908 doing this, but there may be a good reason for it. It won’t be a problem to add something if necessary, though. While working in this area I also added the support structure for the front air-jack (introduced to the 936 for 1978). I made this in fibreglass rather than styrene, hopefully to avoid any warping issues in later years.



The pedals themselves are very similar to the 917/908 style – the clutch pedal is almost certainly an off-the-shelf stock part (probably has a 908 part number). The brake and throttle were possibly adjusted slightly to suit the 936. Master cylinders are generic ‘Girling ‘type – in 1977 the fluid reservoirs were attached directly to the master cylinders, but for 1978 they were mounted remotely to a plate on the frame (hence the bulge and inspection panel in the rad exit duct panel mentioned in my first post).





Some other little details were added – pushrods and clevis’ for the brake pedal, a little bracket which will eventually be the throttle-stop, etc.

Next, some early fibreglassing. The right-hand side of the cockpit simply has the outer skin of the fuel tank as the interior panel, but on the left-hand side there is a fibreglass skin that wraps around the main tubes. It was easy enough to put a couple of radiussed edges onto a piece of scrap blue foam to create the mould. The seat is the same mould I’ve used (with various modifications) on all my 1/8 Porsche projects. After a few evenings laying-up, then some initial trimming, I had the starting points for both pieces:







The interior panel will eventually be trimmed back even more – the top panel in the left-hand sill is removable – but that’s for a later date. It’s possible I may have to modify or even re-make the seat depending on how the mountings work out, but I felt it was worth having it available now in order to progress.

So, by this point I’d got the front half of the chassis largely ‘there’ – still a lot of bracketry to add, but I didn’t want to jump ahead to that too soon.



As with all Porsche racers of this period there are fibreglass outer skins running down to the nose. On the 917’s I made these by gluing together individual panels - it worked, but the result was a little ‘geometrical’. On the 909-03 I made the panels directly on the chassis - messy, and I had to split the panels to make them work. For the 936 I wanted to make these panels in one piece and to have them the correct shape, I’d have to make moulds…

More next time!

SB

[Deathtrap]

I hope you don't mind me giving oohhhs and aahhhs, as this is jaw droppingly beautiful again.
And from reading the texts, you know the car, history and technique really well. I'm learning with each update. Thx!

[jaykay640]

Excellent as always! Looking forward to what's coming :-)