S13 Project Part 2
Following on from Part 1 this post covers the build of the S13 and its transitition to Naturally Aspirated power due to the Hilux stealing it’s drivetrain. Lets get into the details.
I had always wanted an NA racecar, after extracting 340rwkw from my Hilux I thought that I could use that driveline in this car should I ever get cold feet and want to set some quick times. But this car wasn’t about quick times it was about optimising the sum of less parts and thats where the real work begins.
First I needed to shed some weight, at every moment I rebuilt something or optimised an area of the car. The front suspension, crossmember and cast rod setup was all raised and built from lighter, stronger materials.
I met a very smart man named Martyn, he had a thirst for design and CNC and we worked together to produce and design this header system and quad throttle inlet adapters. I spoke with Tomei when I was in Japan and they opened up their N2 Race rolder that detailed all the SR20 development, they had tried numerous exhaust layouts and I learned through their findings what worked best.
A great Australian success story is PWR, I had the opportunity to design, visit and bring home my new radiator. Ill be forever thankful to Kees for this opportunity.
I just started cutting more and more out of the chassis, I very nearly took it to the tip as the amount of rework required was substantial. I was questioning my ability to go on.
The black and white images reflect my mood at the time. I kept grinding though and the new placement of the engine would improve the weight balance of the car.
With everything shifting rearward I needed to extend the steering shaft too.
The sheetmetal work was relentless, I used 0.8mm mild steel to construct the new floor.
All the barwork was taking shape too. This was set to be a comprehensive roll cage.
With primer on I could finally relax, still a lot more work to be done though.
Most of the components were getting comfortable in their new sorroundings, I mounted the coils inside the car, ducted the radiator, made up a heel plate for the pedalbox and had the engine finally in position.
Speaking of the engine, I screwed together a stock NA bottom end, a 1mm Nismo head gasket, ARP headstuds, Tomei Pro Cams, adjustable cam gears and started planning out a more agressive header.
I made this longtube 4 into 1 1.75 to 2.5 header with a slip joint merge collector.
I fitted up some Advan tyres in 235/40/17 front and 255/40/17 rear, I made a new fibreglass dash from a very messy wooden mold, then finalised the suspension and rear mount sump system.
Another WTAC in the books, this time the S13 got to spend some time in the limelight.
Back from WTAC and I painted the engine bay, made a catch tank and started working on the radiator plumbing.
I painted the interior machinery grey and managed to find a set of 4.9 R200 diff gears.
I designed my entire wiring loom on the car and built this from scratch to accomodate the Link ECU.
With the 4.9 diff gears in, the wiring complete, an Abflug carbon diffuser fitted, the fibreglass Aero bar on, the canards fitted, and the dash trimmed things were taking shape.
The Defi guages add to the 90’s styling that I am going for.
Simple lightweight interior panels covered in Acrylic felt look incedible and add a soft luxurious texture to a usually baron interior.
The engine bay turned out perfect, I was now days away from dyno tuning. My chance to finally see if all works.
The time had come to see if all this work would amount to anything.
Day one of tuning highlighted a problem with cooling, the water pump flowed too much coolant and the engine kept running too cool. So cool infact the factory thermostat wouldn’t open due to the lack of heater lines that usually run hot water to the back of the thermostst. I would make up a flow restrictor but I needed to add another thermostat into the system.
It made a decent amount of power for the small camshafts it was running, from memory it was around 125rwkw.
The headers had gone a beautiful golden colour.
My solution for the coolant proble involved a KTM thermostat in the top hose, I made a new restricted swirl pot too just because I didnt like the last design. .
A wiggins clamp and some machined parts bring it all together.
The first drive was cool, I had the time of my life and this car’s demeaner had completely changed. It had power all through the rev range and although that turbo hit had gone it made me drive it differently and for that I enjoyed the experience because it was the same car but it gave a different vibe and that was worth all the time and effort.
Revs are fun!
Remeber half the way through this post I nearly scrapped this car? Well I am glad I didn’t because its come out the other side and developed into a car I couldn’t imagine living without.
I’ll leave it here for Part 2, thanks for reading/ watching.