A OVERSEAS 15GTL

By Steve Swan, Perth Scotland England

Before starting to catalogue the restoration of my Renault 15 we should briefly mention the cars origin.

After the demise of the Renault Caravelle, the Regie did not have a sporty model in their range, if we except the 12 Gordini and Alpines, which were not on general sale in the U.K. and were basically sold for competition, the purposeless Renault 15 and 17 were the Regie's first tentative step to fill this gap in their model range, the 15 and 17 were first released in 1971 and consisted of a four model line up. The 15TL and TS and the 17TL and TS. This was changed in 1974 by deleting the 17TS and renaming it the 17 Gordini. The model line up was changed again in 1976 rationalising the range to just two cars, The 15GTL and the 17TS. These cars were based on the floor pan and suspension of the Renault 12 and were available in three body types, being the 15 which had central door pillars and long rear quarter windows and the 17 which was pillarless and had small triangular rear quarter windows, the 17 could also be ordered as a soft top model giving it semi convertible appeal. All cars were available with manual or automatic transmission and engines ranging from 60BHP 1300cc in the 15TL and GTL to 120BHP, 1565cc in the 17TS with several other engine specifications in between. These cars remained in production and sold moderately, (owing to their high price), until they were replaced in 1980 by the Renault Fuego.

I purchased my car, a 1979 15GTL in the spring of 1986. I used the car as daily transport taking me to and from college 30 miles away when l was serving my engineering apprenticeship, without ever letting me down. After joining the Renault Owners Club in 1987 l decided to rebuild the car and uprate the specification to suit my taste. The car was put off the road on 31/12/87 and daily transport now became a Renault 12. Work on the R15 started in the late spring of 1988, this involved a rough assessment of what parts would be needed. These were ordered promptly as already the spare perts availability on these models was becoming limited, the car was stripped to the shell with all underseal being burnt off and then sandblasted. This showed up more problems than were originally anticipated, e.g. both door pillar covers had rotted away, the base of the scuttle had vanished and most of the seams around the rear suspension peeled away with the old seamsealer!. Eventually the panels started to arrive and imagine my dismay when l was told that the reason the bonnet and 1 inner wing did not arrive was that they were no longer in production, thankfully this was slightly incorrect and after 12 weeks they were delivered. During this time work had started on the shell welding back into one piece, 16 gauge metal was used in all the areas and the shell was strengthened and seam welded.

In between co-ordinating and helping with the above tasks l had to think about steering, suspension, brakes, engine and gearbox, as the original spec gave a slow soft motor car and l was looking for something much faster. There are no uprated steering components available so a new standard steering rack and couplings were ordered, (there is a very important lesson to be learned here which l shall return to it later). On to the suspension and a bit more scope here, the combination finally settled on was spring rates upped 40% and lowered 1.5" it would be worthwhile to note that lowering a car more than 1.5" is not very kind to the shock absorbers unless they have been suitably modified, as these were not available for my car this was the limit and Koni shock absorbers were used all around. The complete front and rear suspension was rebushed, (very expensive), and Renault 17 Gordini front and rear anti roll bars were utilised. As their greater diameter enables flatter cornering.

The braking system was modified next. 17 Gordini front stub axles and lower wishbones were used, as they are reinforced, new front callipers and discs were purchased and fitted, Goodridge hoses and soft copper brake pipe complete the front system. A 17 Gordini rear axle was used as this is fitted with disc brakes, the rear callipers were serviced and found to be working well, these callipers incorporate the handbrake mechanism, which is rather awkward to work on and even when in good condition, gives a very poor hand brake, again the rear end was Goodridge aeroquipped. The only modification still to be done to the braking system is the fitting of a 17 Gordini servo as this is double acting instead of the single acting servos fitted to all other models.

By this time the fabrication work on the shell was complete, the shell was etch primed, the underside was stone chipped and the inside, under floor and engine bay were painted using two pack paint and lacquer. the shell was then partially rebuilt with suspension steering and brakes installed.

The gearbox is again 17 Gordini as this gearbox has the closest set of ratios that were ever mass produced by Renault. It has a very high first gear capable of propelling a car using standard diameter wheels to over 40 mph, the next four gears are very close giving approx. 1000 rpm drop per gear change giving a theoretical top speed of 132 mph at 7000 rpm in fifth.

The gearbox was stripped, (not by myself), and found to be in "as new" condition with no wear evident on gears, synchros or baulk rings, not bad considering the box had done 120,000 miles. The gearbox casings were cleaned and painted again with two pack and the box was reassembled with new oil seals and gaskets, also the diff bearings were renewed as they were starting to show signs of wear. The gear linkage was overhauled and refurbished driveshafts procured, (with great difficulty), to complete the drivetrain, which was then installed into the car.

Now we come to the engine, originally an engine was constructed for the car which was based around the 1647cc engine fitted tho the 17TS, this produced around 120/130bhp. It proved to be very reliable, but was removed from the car to be fitted to my R17 Gordini which had now become my daily transport. I then started to build a new engine for the car based on Alpine Renaults 1800cc fitted to the late A110 race cars which necessitated a trip to France to buy pistons and liners, l estimated this engine should produce 150+ bhp in fast road trim. A point of interest to anyone considering this type of modification. To modify the block, crankshaft and connection rods, (which must be R17 Gordini), Buy pistons and liners costs around 1000 pounds which obviously does not include oil pump, water pump, seals, gaskets, cylinder head, manifolds and carburetters, so it is not a job to be taken lightly. Starting with the block this is pressure cleaned by the machine shop this insures that apart from being nice and shiny all the oil galleries and waterways are clear. Crank next, this is ground which insures that the stroke is identical and the journals are round! this is then dynamically balanced and finally heat treated. Connecting rods are capped and honed for dimensional accuracy on the big ends, then end over end balanced then shot peened (blasted with steel shot to stress relieve) and finally polished, pistons are balanced. Flywheel and pressure plate are lightened and balanced, next the block is bored to accommodate larger steel liners and the bottom of the engine is assembled. Modified head from "Salv Sacco" is fully ported with standard Gordini valves, Renault 18 Turbo guides (bronze) spring seats are machined to accommodate valve lift "13mm" approx, inlet manifolds are port matched to the cylinder head. Timing chain and guides are new standard parts. Camshaft is "Saccospeed" fast rally which apart from having massive lift has 304 deg.of duration, Gordini cam has much less lift and 292 duration, cam timing is done by machining camshaft sprocket to use offset woodruff keys this must be done with the head fitted as the cam followers contact the cam at an angle therefore skimming the head alters the angles and the timing, incidentally the static compression ratio is 10.8:1 on my engine which will run standard leaded fuel and 36 deg of ignition advance max with no detination problems owing to the clever combustion chamber on the Sacco head. Carbs are Weber 45 DCOE's with 36mm chokes. Also modified is the exhaust this comprises a devil 4 into 1 group 1 manifold, (sadly no longer in production), the rest of the system being made from Volvo 740 pipework, which is the correct diameter for a tuned engine 2.25" and the silencer boxes being the straight through type. This engine on the Agra dyno produced the following figures 3500rpm:70bhp 4000rpm:95bhp 4500rpm:106bhp 5000rpm:125bhp 5500rpm:136bhp 6000rpm:148bhp 6500rpm:157bhp 7000rpm:163bhp as the figures show the motor tends to go wild after 4000 and it can in fact break traction in first four gears if it is wet but it does idle nicely will pull from idle no problem if you are careful and best of all will take full throttle cleanly from 3000rpm and when driving to an event will manage 30mpg cruising at 65mph. Please note the motor will rev past 8000rpm comfortably but the "standard" value train is no use past 7000rpm therefore we did not dyno the engine past 7000rpm. I estimate it peaks at 7500rpm with about 170 brake but the rev limiter is set at 7500rpm for safety sake. The distributor incidentally is Renault 17 Gordini suitably modified.

Back to the body shell, the next job was to finish painting the shell. The car was painted by a friend and l decided to have a stripe painted in, the stripe was a replica of the original Renault Boutique item which sets off the lines of the car nicely. To get the car flat and then the depth of shine it took 4 weeks work, but l have had several compliments on the finish of the car which stands as a testimony to Big Ed's ability with a spraygun.

Now comes the tricky bit putting it all together without breaking anything. Most of the brightwork trim was renewed which was costly and time consuming waiting for part to arrive. The various seals on the body work were cleaned and fitted, the only ones that really needed replaced were the two door seals which were no longer available but as luck would have it l discovered that new FORD Transit side door seals actually do the job much better than the originals and they were quite cheap. All the body glass and door mechanisms were refitted by another friend who strips and builds cars for a living, the screen trims and side windows had never previously fitted or worked so well.

The interior was tacked next. I have never had any prowess with a needle and thread so the car was taken to a local trimmer, an interior design was agreed on and a week later the job was done. The car is trimmed in two colours beige and black, originally it should have been all beige, but a previous owner had the seat edges trimmed in black which livened up the interior on end. A black head cloth was also fitted because if you have the misfortune to be in front of someone who is driving along blissfully unaware that he/she is on high beam, the black head cloth kills the glare.

Wheels and tyres. Obviously these had to be changed, a local motor trader was at the motor show and saw an advert for wheels that would fit my car. The wheels in question were very smart and only a fraction of the cost of importing a set of Gottis from France. When the wheels arrived the tyre choice had already been made, l use Yokohama A008R's not perhaps the most fashionable tyre in their range, but they certainly give excellent grip even in the wet , but not on surface water, a must for a front wheel drive car which is very weight biassed to the front wheels and which will want to understeer when pressed hard.

Now we have a car again, all that remains to do is testing and finalising, MOT and TAX. The car was now taken to another friend who has been a Renault mechanic since the late 50's to have the suspension geometry steering and brakes set up. The suspension and brakes are fairly straight forward if you have all the information to hand, but the steering is another matter, the steering rack height is critical and if it is incorrect heavy steering, unequal steering, bump steer and loss of self centering are the problems encountered. Unfortunately when l removed the original steering rack l did not mark it's height and this gave my friend a severe headache as the only way to reset the rack, (according to Renault), it is done by a series of frames and mirrors which no one has, fortunately for me he had his own method of doing this involving rods and spirit levels and it certainly worked, l was also told in no uncertain terms never to remove a rack without accurately marking it. With all the above being completed the car sailed through its MOT, insuring the car did not present too much of a problem although it was rated group 8, which was expensive. l only use the car in summer, but it works hard for its keep when in use, it is certainly original and it has picked up several awards at various Renault Owners Club meetings and is a sheer pleasure to drive. So there you have it, another possibility for a future classic, who knows only time will tell.

Finally let me mention the rouges gallery, otherwise known as the people without whose help this would never had been done. Raad: constructing of body and general assembly work Harris: for shouting at Raad SALV SACCO: all engine work D A Reid: gearbox, suspension, steering and brakes Big Ed: paint work Bruce, Jason and Bob: for the spare parts and finally Liz for managing to stay calm thoughtout the duration, l will have to get married now.

Steve Swan sold the 15GTL to Paul Godfrey who owns a huge collection of hot renaults, 30 at last count.

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