1973 Chevron B23 - 1 (Chassis #1 !)

This exciting restoration project has been a major focus in 2023 & 2024. It is the very first project listed in C&G for a good reason. We will be competing in vintage races this spring in the Group 7 FIA 2 liter class. While driver Jason Richardson has taken several trophies in the 907K, this chassis is more modern and this car will compete directly with the other drivers in Ford GT-40 and Porsche 908-03 that have led the pack to date. SVRA and CSRG race groups have some wiggle in terms of era and power so this car will be a better match at the front of the pack.

Working directly with Chevron in the UK, we obtained a few missing components, corrected a few “modifications” made to suspension parts, and completed the sympathetic repairs to the new old stock original factory bodywork which is believed to be one of the very last sets of FGR hand laid at the factory in the 80’s.

This B23 was delivered new to Italian racer and importer Eris Tondelli and it’s race history is being documented now with records we are sifting through. It raced at Monza, and it went on to compete in many hill climb races in Italy and Switzerland. Boxes of spare layshafts and gear sets came with the car and it was clear on inspection that hill climbing ratio setups were different from higher speed road courses.

Starting some time in the 1990’s, my late friend Neil Johnson began the restoration. The steel frame is all original, showing a few small repairs, and was re-skinned by Harold Drinkwater with fresh aluminum alloy sheet. A thick coat of glossy dark blue grey chassis enamel almost hid the very important Arch Motors chassis number stamped into the rear upper frame member “AM 73 B23 1”. We did not know this stamping existed until much later in the story when a photo of it would help establish the car’s originality.

15 years later, Neil was, sadly, never able to complete the project and it was not marketable as a project car. It sat in disarray with chassis separated from body panels and boxes of parts. Furthermore, the few documents and photos we found with the estate were very confusing. We reached out to experts in the US to understand the origin and value of this car and learned little about it. What we did learn was that in 2023 there are few who want to invest the cash to complete a project car of unknown origin and fewer and fewer people with the skills and resources to do so. Had I not bought this project, the next offer was a shop who would part out the transmission and scrap the rest.

Taking on this project was an emotional decision as Neil was my friend and my shop used to be part of his machine shop in Hayward in 2006-11. Every day I would go to work on the two 907K continuation cars there, one of which was Neils, and I would pass by him working on the Chevron’s bodywork. Eventually, the shop was sold, and the car was disassembled and stored in pieces at Neil’s home. It sat with no progress for over ten years.

After starting to piece the project together, we discovered that Chevron still existed in the UK and many of the original fabricators and engineers were able to help us understand what we had to deal with to get it back together. More importantly, they reviewed a document that we did not know we had in a binder when we bought the car and, with many more photographs sent to them, they were able to verify that is was not only an original B23, but that it was the very first chassis they made. They sent a proper factory serial number / ID plate and documents confirming it’s identity and origin. Now, I could justify the man year of labor and significant expense it would take to restore the car to it’s original condition in 1973.

All the major parts seemed to be there and intact, like the magnificent Hewland FG-400 transaxle and a (possibly) freshly built and dynomometer tested Cosworth twin cam belt drive engine, but every nut and bolt on the car needed careful examination. The binder had dyno plots, but no receipts or specifications for what the engine was internally. Even more confusing, was that the completed engine, was missing all of it’s crank fired ignition system. As of this typing, this engine waits to be started with a new ignition system installed.

We could not assume anything was torqued, wired, plumbed to final and correct specification. We consulted with an expert F1 engine builder and engineer to identify the capacity and type of engine. We also needed clarification from Chevron on strange features of the frame that did not make sense.

One of the frame tubes in the cockpit has a pipe fitting brazed into it at an odd angle. We sent many photos to England and were amused to find out that the frame constructor frugally used older B19 / B16 frame tubes that had a fire extinguisher pressure line attachment provision. This setup was later banned just before 1973 by the FIA. Along the many turns in this project, often we learned to just ask Chevron - everything on a Chevron is very well thought out and engineered - there is nothing superfluous on race cars in general, but a Chevron is a wonderful study in doing as much as possible with as little material. And what a pleasure to work on these cars - compared to a Porsche 910 with its forever bonded to tube frame FGR bodywork and limited access.

Chevron helped us with the bodywork preparation as we were unaware that all the cars at that time were delivered in gel coat - no paint! We had black gel coat to work with and the car was originally red as delivered. When this B23 arrived in California, Neil removed the actual original tattered bodywork and somehow imported the very last set of remaining panels. The aforementioned binder had no receipts, just the most important documents like log books and customs paperwork in Italian.

Neil was a great engineer and fabricator. He made up custom exhaust, and many of the suspension pieces that needed to be copied due to corrosion. He was also very fond of straight and perfect bodywork and applied a significant amount of filler. We tried to carefully fare the surfaces for appearance, but remove most of that weight to keep the car within original specs. Many many hours were spent replacing wrong fasteners all over the car with certified aircraft AN and NAS hardware. Over the years, a lot of stainless steel and junk bolts got into the mix.

This project was fun, and it seemed to require endless tweaking of the bodywork ( 30 year old new old stock FGR panels are not dimensionally stable unless on a chassis), but it is ready to go for it’s first track shake down in February of 2024.