S15 Project Part 1
I bought this S15 as a write off in 2010, stored it till 2020 in a shipping container and starting building it to create a Roll Cage Course which you can find on this site.
I stripped the interior and the sound deadening out of the car then designed and made a hydraulic tube bender which you can also download the plans for.
I stripped the car down to a shell and sold all the running gear for twice the amount I originally bought the car for, it had only dont 30,000km and was in pristine unmodified condition.
This rollcage took some time but the results were well worth it.
With the mild steel tubes all welded in I could now concentrate on the gussets.
The gussets turned out great but were a challenge to TIG weld to the facory sheetmetal.
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After I moved the workshop back home things escalated quickly. I had started to learn how to CAD and now had a new direction for the build. I chopped the front and rear end off and went to work figuring out the rest.
With the JIG made I could now continue mapping out the next phase.
The wheels in question are ex Japanese race items pulled from a Porsche, they are Rays Forged Monoblock Magnesium Ceterlock Rims measuring 18×11 front and 18×13 rear, this means I can run Porsche Cup Car race slicks which are easy to get here in Australia.
I spent the best part of a year loooking at options from all around the world, I was open to anything but I wanted to create a car that had a very 2000’s era touring car theme about it. I wanted the car to showcase my ability to create and engineer something thats evokes excitement, nostalgia and excellence in design, engineering and fabrication.
Then it happened, an add popped up on RaceCarsDirect, a seller from Indianapolis had a bunch of ex Indy Pro Nissan VK45 V8’s complete and ready to run, every other scenario in my head went out the window and this became THE direction. Architectually the motor works perfect for my application, I spoke to the seller and had him send through the critical dimensions of motor hight, the tall Kinsler eight throttle inlet manifold stands tall but the completely flat structural dry sump allows the motor to sit low and flat.
The motor sits back behind the centerline of the front axle and will create an optimal position for weight balance and suspension design. I’ll share some specifics about the engine, its a Nissan VK45 block with a billet Bryant flat plane crankshaft that reduces the stroke and capacity to 3.5 litres, the internals are as good as it gets with Carillo rods and forged pistons, the valve gear is all titanium, the castings for the accesories are all specific to Indy and perfect for my application, the dry sump setup is a work of art with integrated Peterson oil filter plumbed by Brown and Miller fittings.
Like everything else on this engine the intake is a work of art, the Kinsler 8 throttle system is shrouded in a carbon airbox, when the butterflies open through the smooth function of the linkages the intake valves can be seen directly down the ports hinting to a power productive path of fresh air. The electrical side of things are all comnplete too, crank trigger, cam trigger, pressure sensors, heat sensors, coils and everything required to make this run is all included and in amazing condition. The looms concentrically twisted and shielded in fireproof Raychem, I even have the complete wiring diagram to be able to utilise all of this on my own ECU.
I am extremely excitied about this build and the main focus for me right now is to develop and plot my front suspension system, the arrival of the motor makes this design a lot easier as I can utilise the motors pick up points into a structural frame that will support inboard dampers.
I have learned a lot about how technology can reduce my workload in this project, I picked up a 3D scanner and it’s allowed me to complete scans on the VK45 motor and bring these into CAD to start developing the model for the front and rear motor mounts. These will have very important roles in the front end structure of the S15 Project.
To begin I scanned the VK45 motor and focused on the front mounting provisions that would have secured the entire driveline to the Indy cars rear bulkhead. From here I can develop a motor plate that houses the 6 mounting bolts for the motor, steering rack mounts, forward upper and lower suspension wishbone mounting provisons and damper mounts that utilise rocker pivots.
This video should give you a good idea of the scanning process.
On the rear I needed to scan the same mounting structure to facilitate a rear motor plate that creates a bulkead mounting provision that will create the firewall of the chassis, mount the starter motor, the dry sump oil tank and then a structural support that reinforces the suspension rockers on the front of the motor. Yes a ruler could have been used to pick these points but the amount of extra information a scan provides is super powerful, I could have spent 2 hours in the garage measuring everything, creating templates and possibly introducing costly errors in the process. Instead a morning spent scanning the necassary areas gives me every detail I will need to know without ever revisiting the garage with a tape measure.
Now the tedious task of CAD design begins, I am learning so much all the time and the design process is extremely satisfying.
Don’t pay too much attention to the aero side of things as this will change as I develop out the chassis and suspension but you can get a feel for where my design process is heading.
You can see how valuable the scan data is when it comes to CAD design.
I was out on my Go Kart and these used slicks were dropped off to line the track, I asked the track owner if I could put them to use, he obliged and now I have the N2 Porsche N2 Michelin Cup Slicks to fitup.
We are in racecar land now, I had drawn my own uprights in CAD but finding bearing specs, working out required tolerance’s and then walking the fine line between weight and strength had me searching for other options. A trip to Garry Rogers Motorsport and all my questions were answered.
The hold up right now is the Trnasaxle choice, I want to put a 6 or 7 speed paddle shifted Sequential Transaxle behind this VK45 and until I settle on something I cannot finalise my design.
I’ll leave it here for Part 1 but stay tuned because things are going to get even more exciting in Part 2.