Built, Tuned and Tested
The 2020 Oxborn RS (@Prium)
When browsing the kit car forums, we happen to hear of a very popular lightweight, mid-engine, open wheel, single seater kit that is advertised to be a great little track/autocross focused car and is rather easy to assemble and it won’t break the bank. Looking on Oxborn’s website, we find their kit in three variations. The Oxborn RS, RSR and the RXR. Each with 3 different engine packages for those that want either the basic entry or the high performance, in your face death trap performance. Needless to say we decided to take the base model Oxborn RS to see what you can get for the entry market.
Our kit arrived at our shop in 3 months time. The chassis and body were together in a neatly built wooden crate box, a stock 1.7L naturally aspirated engine and transmission in another wooden crate and the rest of the parts in about 15 large to medium boxes, and one large instruction manual. The manual will tell you the parts inventory list, parts that are needed, page by page instructions with clear pictures, diagrams and instructions, as well as recommended tools, that of course come separately. Estimated build time is 200 hours. So we got to work.
The kit was rather easy to build on the chassis side. All the components, bolts and bushings were delivered with our kit. Oxborn however sent us solid disc brakes all around, so we decided to upgrade the stock brakes to some high performance Bremsi discs and pads and installed some 18" wheels. The calipers will do the job just fine, and we ditched the electric power steering unit because it’s not really needed for a car that will be this lightweight. The chassis itself was a tubular bare frame steel, so a powdercoating was put on to secure the elements from eating away at the steel. Then it’s all about riveting the floor panels together… Our favorite task… Once all the panels, boom-mats flooring was in place, we installed the fuel tank, fuel lines, brake lines and electric cables, all of the switches and the electronics, which was really just a basic all in one electronic gauge from our tuner, we bought ourselves a performance racing seat and installed it compared to the basic hard seat that came with the kit.
For the engine, the manufactured date was stamped from 2012. While the engine was out of the car, we decided to order a performance kit for our little 1.7L. We put in a forged piston kit, a performance twin-cam and valve spring set, fuel injectors, spark plugs, intake and a stainless steel performance exhaust. We also found a 6 speed transmission with a lower gear ratio than the 5 speed, so we went and swapped it for that. All in all with a custom tune, we brought the 1.7L to a screaming 155hp! Once the engine was finished, it was off to mate it to the chassis. The chassis was perfectly suited to fit this engine precisely. We put polyurethane engine mounts so the engine won’t vibrate us to death. The install was easy. Once everything was secured, we connected all of the lines and wired it up to our ECU and we were now in our go-kart phase. On to the body!
For the Body, it comes in two major fiberglass pieces and a wind screen. One is the main body and the other to cover the engine. This makes it nice, easy and inexpensive for us to knock out any body work to smooth out the edges and take it to the paint booth for primer and color. We went with the Oxborn Green and wrapped some accessories in faux carbon for that look. After paint, we carefully carried the body and mated it to the assembled chassis. Then it was down to installing all the lighting and the long hours of riveting some more to secure the body to the chassis, and at long last. The build was complete!
After some final chassis tuning and alignment, and going through the paperwork, DMV lines, inspection checks, and the very crazy California registration fees, we unfortunately are not street legal… But it is registered to us! So on to the trailer it goes and we took it to our local track.
It’s Open Track Day Weekend at Willow Springs International Raceway. The Oxborn was taken off the trailer and already some people were eyeballing the car and asking questions. Along with a couple of Oxborn owners to see what we’ve done to ours and exchanged some tips and information. The joys of these kit car communities is after all coming together and sharing our stories, ideas, tips and tricks and of course showing off our builds. We went around Streets of Willow in the full Counter Clockwise rotation. The car being so lightweight and agile handled the course flawlessly with our current tune. Everything ran perfectly and it was a full day of fun. Then it was time to go home.
We were very impressed and happy with our Oxborn RS. The build was easy and rather inexpensive with our build totaling $29,700 AUD, and the performance shows. All in all, we recommend you get one.
Thank You Prium for the car!
Performance Stats and other photos