S15 goes V8

Firstly I have to say how excited I am to be posting this, it’s been in the works for over a year. Before we get too deep keep in mind that this project is now part of our extensive ETS Projects list and contains much more information including CAD file downloads and details on fabrication, click HERE to head on over.

My Nissan Silvia S15 has been in my ownership for a long time and you would have read about smaller apects of the build on these very pages, my initial plan was to share the driveline with the Hilux but instead of doing exactly what I had done in the past I thought I would expand my horizons and look for something a little more special than the humble SR20.

Of all the cars I have built the SR20 provides everything I need, in Turbo form it’s a formidible engine with extreme potential but in Naturally Aspirated form you really need to go back to the drawing board and re-engineer a lot of aspects of the motor to produce an exciting amount of power, as I have found out in my NA S13 build.

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.

The price tag was $15k US but I immediatly saw the value here, the biggest highlight was that these motors are race proven and meticulously maintained with all documentaion to prove this. Ill get into more of the details soon but the spec sheet read like a wish list and you just couldn’t build the same engine for 5x that price. Back in 2009-2012 teams would lease an engine for around $85,000US per season so to have the opportunity to own one was something I couldn’t resist.

Architectually the motor works perfectly 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.

After working through the payment side of things I was ble to ship the engine home in the same container as my Born Free BMW and eagerly awaited both of their arrival.

Once home I was able to see the motor and start to understand it, it truly is a work of art and something I still can’t believe I own. I wasted no time seeing how it would fit in its new home.

Out came the angle grinder to trim the required area for optimal placement. The dash bar on the roll cage I made was perfectly inline with the rear bellhousing mounts for the VK45, these engines are structural and complete the back half of an Indycar chassis meaning that the suspension forces run through the engine. The studs on the back and front of the motor will form the perfect pattern to mount the engine into the chassis without requiring too much structural tubing joining everything.

With those cuts complete I could then prepare the chassis for the JIG and start laying everything out where I needed it.

I added some rails to the chassis JIG to support the motor and slid it into position. The hights will change slightly but I plan on 3D scanning the engine and doing most of these calculations in CAD.

The motor sits back behind the centerline of the front axle and will create an optimal position for weight balance and suspension design.

Having so much freedom here is both daunting and exciting, you can see that the header layout wont be too difficult to create, I just have to give that beautiful dry sump area enough room.

Once the chassis JIG had enough provisions to safely support the motor I could push the whole lot out of the garage for a clean up. I reshelled my 180SX into a street going shell just recently but Ill follow this post up with that once I sift through my images.

I promised to share some more details on the engine so lets fire away, 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 its 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.

The chassis will be raised around 50mm on the JIG but this is essentially full bump hight.

Almost everything else missing on the car will either be sourced from used race cars or completely made by hand.

Since building my Hilux I really miss the constant headspace a build like this occupies, always searching for a way to solve a problem in a functional and aesthetically pleasing way.

It’s time I got back to the drawing board, stay tuned for more updates and thanks for reading.