This car has been a family member for more than 20 years and was originally a red R12L. I had done regular work on it whilst in the ownership of its previous keeper, including an engine-swap using our terminally rotten, first ever R12, a 1971 model, as a donor.
Our 1972 R12Ls previous owner for several years was involved in a minor accident; a French man stepped out in to the road at Crystal Palace Parade and hit the car causing several dents in the otherwise solid bodywork. Both parties were OK, but shaken.Then, soon afterwards, the gearbox ran dry of oil and caused bearing failure! The owner then lost confidence in the vehicle and he offered it to me for free. I snapped it up, as I knew how good this car was, even with the dents, and broken gearbox, and it has been ours since 1995.
My wife ran this car as standard for several years, though we did upgrade the interior to TL spec in 2001. However, I had always wanted to soup up a R12 so in 2002 I fitted a R5 Gordini Turbo engine, with a modified Fuego 5-speed gear box and ran it in this configuration until 2007.
The set up worked well but never realised the true potential of the R5G Turbo engine, I commenced a major upgrade of the Gordini engine, and ran a pressurised carburettor, an intercooler and high pressure fuel delivery system, programmable ignition and much more. I changed the cars body colour to orange, it looked fab and went like a rocket, with a comfortable rolling road test of 175 bhp at only 14 PSI boost. But reliability was an issue as it cracked 2 cylinder heads.
The brand new standard R5G Turbo clutch (rated at 150 lb ft. torque) was also slipping under full throttle and my only option to sort this out was the fitting of a race-type ceramic clutch, which I felt may make the driving of the car uncomfortable. I decided enough was enough and opted for a larger displacement, normally aspirated engine, and taller gear ratios.
After a lot of working out and trial fitting, cutting and making everything required to fit a 2 litre OHC R18 GTX engine and gearbox, I found out that the cylinder heads had cracked on the turbo installation due to the custom made intake and exhaust manifolds I had specially made for this one off application! These were the one part of the modification that I was unable to do myself and to be fair to the company that made them for me, they have now altered the way their manifolds are designed and they have slots and loose fitting joints to allow for expansion and contraction.
The weak link in the Gordini engine was the very thin casting of the roof of the water gallery! At present the car is off the road while I fit the 2 litre engine, which obviously I cannot leave standard!!! There are lots of goodies in the pipeline for this including twin 45 DCOEs, forged pistons, balanced and blue printed, programmable ignition etc.
I have also sourced from a scrap RHD R12 TS an instrument cluster with rev counter and full complement of dials which is a really nice addition that I have had to rewire for.
The original seats have been replaced with those from a 12 TS. The internal structures were in a terrible condition so I have rebuilt the frames and springs. A small armrest was sourced from a scrapped Mazda and welded on to the driver’s seat. This is a smaller version of the one found on the 12 TL , and I find it a comfortable addition to the interior, especially on long journeys. The seats have now been recovered in a nice, shiny leather with minimal grain, to replicate the 1970s’ style, and have double rows of stitching copying the original Renault 12 TS embossed pattern.
The Renault 18 GTX 2 litre engine and gearbox have now been rebuilt. The engine has been fully balanced to 0.5g, has forged pistons, and an increased compression ratio sports cam profile with modified adjustable timing gear from a Fiat. The cylinder head has been gas-flowed , with ports and manifolds matched and polished. The engine has been fitted with programmable ignition, with a throttle position sensor, engine temperature sensor, and a crankshaft position sensor.
The exhaust system is custom made stainless steel throughout, with expansion joints , equal length manifold tubes, and twin tail pipes at the rear. An electric fuel pump and pressure regulator have been fitted, the aluminium radiator has been custom-made and has 3 small cooling fans mounted behind it. The original distributor has been removed and blanked off at the cylinder head, to allow the use of a coil pack from Peugeot/ Citroen. The crank sensor from a Ford Cosworth has been used, with the front outer v-pulley machined off the crank bottom pulley, and a segmented trigger wheel adapted to fit. The cam belt cover has been modified to allow the drive belt to run the alternator on the opposite side, and various brackets have been made up to suit. The engine also uses an aluminium sump from an Espace.
I fabricated the engine mounts from 4mm plywood templates and shaped them to fit on the car. I then then copied them in 4mm steel and welded them together. The front crossmember and lower valance had to be removed for clearance so I made a curved chassis reinforcer to take the place of the crossmember, then a new front valance was bolted back on to retain the original front appearance. I also made a dropped version of the lower tubular link bar between the chassis rails. The engine leans over at approximately 15 degrees which made the fabrication of mountings difficult, and four were required altogether; 2 use original R12 rubber blocks, the mount high up at the front uses a square rubber mount from an unknown Renault, and the one at the rear of the cylinder head uses a Mini stabilizer link with polyurethane bushes to stop forward movement, especially under heavy braking.
The R18 GTX transmission uses shortened and modified driveshafts fitted with the inner CV joints from a Fuego. I cut out the R12 floor and fabricated a transmission tunnel to allow the gear linkage from the Fuego to fit, and modified the transmission mountings and chassis accordingly. I have used the bell housing from a Renault 25 with a conventional clutch lever arm.