Local content programmes affecting the SA motor industry in the mid 60’s demanded that the local car companies raise their game to meet the requirement. General Motors South African did so in style and upgraded all facilities massively. Firstly the Product Engineering Division was housed in a new building and was very simply a first world activity containing every engineering discipline imaginable from metallurgy and chemical labs, to component and vehicle testing, a styling studio, engine dynamometer test facilities, component engineering and drawing office. The Fabrication facility could literally make prototypes of practically anything needed in the development of a car.
To me as an experimental engineer this was kid in a candy store stuff and I had got the job in a most unusual way….by upsetting the engineers in two stages whilst still working in the service division. We’ll cover how that happened as we go along in this two-part story, the first of which covers the build of a rather unusual car (for GM at the time), which despite being a success, resulted in the team who built it being undermined. The second part deals with Karma and unintended retribution.
I had previously spent two years in training in the Service Workshop and assigned to a posting as product service engineer for Firenza in the tech department. I was given the additional responsibility of managing the repairs on customer vehicles requiring attention through our customer relations team….as well as running the service station rolling road. On one such day in 1970 I was supervising the ignition switch repair on a Chev SS when the general manager of the styling studio strolled in looking for me. Please appreciate that in those days, for us folk on the front line to have a general manager looking for you was either good….. or very, very bad…..this was akin to talking to God. In this particular case it was to set in motion a turn of events that would span four years before the book was closed.
The manager was an American, Jim Ewen. He had found me only because one of his staff, Ken, a styling engineer working in the studio and good friend of mine, had responded to a comment he made about an Opel Kadett he had seen running at the local ¼ mile drag strip the Saturday before. He was surprised to find out that the Kadett was in fact run by a GM employee*. That was the reason he found me. I was equally amazed to find a senior management petrolhead in the system*. Even better, he was seriously concerned that my Opel was the only GM product doing the business at the track….his pitch was extremely straightforward…what can we do to fix this? Absolutely blown away by the event I could hardly respond but agreed to meet him at the styling studios during lunch.
*GMSA, unlike Ford down the road, was not a place crowded with car enthusiasts. For some uncanny reason this was one piece of the collective at an otherwise first class manufacturing operation that was missing. I often made the comment that we could have been building washing machines…(we did build fridges) and that apart from the assembly line workers, 90% of the folk would probably not have known the difference.
To keep this short, after a fairly broad discussion around the possibles, it came down to simply what was available in terms of a car. Bear in mind that GM was not in racing…. I really understood this and because what we were plotting was probably a treasonable offence, resolved to run the car under the local dealer colours if and when it all happened.. “Come with me” he said and together we strolled out of the studio round the back of the Engineering building. Amongst the hydraulics and Power feeds for the Dyno and flow bench equipment stood a car that I recognised immediately…the original prototype Ranger 2.5 styling car**. It looked a little sad, because that parking area was the boneyard for test/development cars scheduled for the chopper. I was given the keys and asked to see him the next day with a budget and a plan.
The Ranger Styling car – Opel Rekord, Chevy 2.5 L4 with revised front fenders and Vauxhall Victor grill.
** A little history about the GMSA Ranger. As noted in the story “GMSA Finding new roads”. In the late 1960’s GMSA carried most of the world GM brands, one of which was Vauxhall. By 1968 it was decided that the Vauxhall Victor would not be replaced after a run of some 10 years covering three models, the F (1957), FB (1961), and FC ‘101’ (1965). The decision was made to do the first badge engineering job at GMSA by badging the Opel Rekord as a Vauxhall along with styling changes including the use of the FD Vauxhall victor radiator grill. GM’s market share had, over the years been large enough to sustain two Dealer networks….OPEL CHEVROLET GMC and VAUXHALL PONTIAC BEDFORD…but that was changing and the decision to go to a single franchise was known to be on the cards…something very upsetting to many GM dealers. This car arrived at just that time and with the Vauxhall brand name not being at all strong, the greater dealer body kicked against the Vauxhall branding for the car. The stock yard was filling up with Vauxhall badged Rangers and with many of the split franchises still operating, GM were forced to capitulate. The marketing programme was turned upside down and the car re-badged as a GM Ranger before launch… ‘South Africa’s own car’. The Rekord and Ranger ran side by side with common specifications for four years with the addition of the very well accepted Ranger SS performance version the only difference. In 1972 GMSA decided to brand all local product under the Chevrolet logo.
Wow…this was like all Christmases rolled into one but I realised that whilst being an opportunity….it could go seriously pear shaped. Here I was getting involved in something that had not been done before and worse, doing it in a hostile environment. I did not sleep well that night but woke the next day with a completely different resolve… “Go for it and to hell with the consequences” was more like it. I collected the car that day and had time to roughly assess what I would need in special parts. The list was not too long, as I had decided on doing most of the work on the car internally thus minimising the use of such special parts and to see what we could use from available GM sources. I gave Jim the ridiculous (by today’s standards) figure of R2000 for the project!
MUSIC: Me and Bobby McGee Kris Kristofferson: This was the music of the times and the words “Freedoms just another word for nothing left to lose” encapsulates our eventual attitude on this project.
Firstly I had to find a partner in crime to help with the build and then had to get management in the service w/shop on-sides. The first turned out to be easy, there were a few trainees with petrolhead tendencies and Trevor was immediately keen, I offered the ¼ mile drive to him as an incentive, I was quite happy to keep running the Kadett myself. Trevor ‘volunteered’ in a flash and the team formed as quickly as that. The second task had to be handled carefully simply because we needed our management in the service dept to support the programme. It was a question of approaching the right guy first, so Harry Schwarz the senior foreman was pulled aside and brought into the picture. He too was ‘in’ like a shot and he came up with the covering story that we were preparing a styling buck for the studio and building it in an unused paint shop. He was great because our normal workshop loads were adjusted and Trevor allowed to spend part time eventually working on the car.
The deal between us was that I would prepare the engine gearbox and axle main components and Trevor would take care of the vehicle prep and build. It worked a treat from the get-go and we worked two or three nights a week and Saturdays. For two youngsters to have such an opportunity was fantastic…… so neither of us were going to screw this up by not giving the full beans. Looking back now I am in fact amazed at the way we went about the thing for two absolute greenhorns. The decision to build the machine as a ¼ mile car made the choices surrounding the chassis and brakes absolutely straightforward…. but the engine and drivetrain took some head scratching. I had only ever race-prepped the 1000cc engine in my Kadett and tuned good numbers of GM streetcars. I had ties with one or two Product Engineering folk who had been involved in engine tuning on the big four cylinder Chevy in recent times but was not impressed with any of the executions or the power they produced, so a different plan had to be made. As far as the transmission was concerned….that was easy. The standard Opel based four speed gearbox suffered a similar awful ratio selection (though not quite as bad) as is found on the British Fords of the time…the dreaded ‘Dagenham gap’…that appalling hole between 2nd and third gears on all small Fords. This could only ever have been specced by a drunken transmission engineer on cocaine.
For my sins I had spent a lot of hours in my spare time devouring specification manuals on all GM product stashed away in every conceivable corner of the business. In the process I found a talent that has served me well over the years. I was a walking GM specification manual. Technicians in the workshop never referred to books when I was around…whether it was a valve spring pressure, head torque, or gear ratio you wanted…..done. As a consequence, I had the information of every available special part in the GM kingdom right on hand….and Opel Germany built a close ratio ‘box under the title “Heavy duty option” (not bold enough to say Competition Option) almost unnoticed in the subtext of a Commodore parts manual…..I ordered one simply by issuing the part number quoted and not telling a soul…..perfect….. R600 off the budget.
We’ll get to the engine which is the best bit, but the next task remained the rear axle and particularly the choice of final drive and installation of a limited slip differential. Again staying abreast of what was happening in the company at a tech level paid dividends. Our engineering ‘buddies’ were just at that time busy with the chassis work on the new 38/4100 range to be launched two years down the line. The new car was to be a development of the Rekord/Ranger, newly styled but to be available with six cylinder engines. The floorpan of the old and new were basically common…and I knew that sample (bigger) model 78 rear axles from Borg Warner were undergoing fitment trials on the new cars…so I asked if there was a spare one. There was. Borg Warner had sent three axles with varying pinion angles for final check…one was hopelessly out and scheduled for the junk box…it found its way to the project instead, free. It was then sent back to Borg Warner to have a 4:1 final drive installed and a limited slip unit. Not free… R400. We adjusted the pinion angle to suite the application and half the budget was now done. There were three reasons for selecting the larger axle: 1. Axle ratio availability, 2. limited slip availability and 3. the use of 5 stud sideshafts to take the proposed wider-tyred 14”wheels.
The engine needed a completely different approach to the job done by product engineering. The team there had followed the rather stereotyped standard of the time applied on small four cylinder engines, by using twin sidedraught carburettors on stub manifolds…bolted to 8 port cylinder heads from the 3 litre Mercury Marine version of the engine. This looked like trying to make this engine a revver….that was not going to happen so I went the opposite way entirely using the 2.1 litre (130) six port small chamber cylinder head…..seriously ported and modified…..I had more sins…. and was bloody good with cylinder head mods. 100 hrs work produced a masterpiece….. it looked nice anyway. My view was that as a first stab this had to be an engine with big mid-range torque as the primary characteristic. The engine came out at 2563cc with flat top forged 283 V8 pistons (found after a search through our parts department) and starting static compression ratio of a moderate 10.5:1. (best I could get with flat tops)
For the camshaft I had thought of a magical Isky of sorts but the budget looked a little sick after the purchase of a brand new 48IDA Weber Downdraught, so it was a call to Basil at Superformance. Along came a TR 71 at just R100…a 298 degree duration profile used on 1600 race Fords of the time. Put to work in the Chevy with a higher 1.75:1 rocker ratio raised the 10.5mm lift to a more respectable 12.4mm in the big engine. Little did I realise that the consequent increase in valve accelerations would give us some initial grey hairs in valve train surge.
The use of the 48 IDA on long runner inlets to the siamesed ports just seemed to be a sensible starting point. We put the engine together by first running the new sub using stock hang-on parts, cylinder head and cam. I wanted to do this to get a good idea of stock rear wheel horsepower before we installed the good bits, as well as getting a squizz at the bores after run in.
The before: 72 Bhp @ 4300 Rpm. (90BHP flywheel)
The after 130 Bhp at 5300 Rpm. (162BhpFlywheel)
We had run into a valve surge problem at 5350 despite running decent small-block springs good to 7000 on the V8. Those valve accelerations were partly to blame and I quickly learnt how to tighten up on the system with guide plates and larger dia pushrods which solved the problem….. but not before we were forced to run the car in its first ¼ mile….. just as it was.
This is the car with full Dealer Logos and on its first run.
Straight off the Dyno to first ¼ mile run – Trevor restricted to 5300rpm.
Music: “You never can tell” by Casino Steel we had no idea where this would go ‘we could not tell’
Scrutineering the previous evening was amusing with the Fordies making comments about the old tractor engine…straight into the fray against a few 3 Litre V6 Capris. We were not too confident at being restricted to 5300Rpm but prepared to give it a full go anyway. We need not have worried, the gearing was perfect, the engine hauled and despite the restricted rpm, cracked a 15.3…first up faster than the Fords by half a second…..More to the point, that was the first win in an unbroken four year run in the 3 litre class. It was also a bitter sweet day for us, because it just so happened that our leader Jim Ewen had to leave to go back to the ‘States after completing his time at GMSA that very day. He at least had the satisfaction of watching that first run and knowing that the project was a success before dashing off to the PE airport to catch his connecting flights back to Detroit.
The next step was to optimise the package, so a fix to the valve train problem…. and back to the Dyno. Continuous increases in carburettor choke tube sizes resulted in linear increases in power…and we ended up almost removing the choke tubes from the carb!…the engine wanted more air and ended at 46mm choke tubes in the 48mm barrels!
Final power: 151 Bhp at 6200R/min (188bhp flywheel)
The next run at the strip showed the cars potential with Trevor running a 14.1 at 97Mph. The Ford Engineering guys arrived with a triple carb V6 Capri running in the low 15’s…and they tried numerous times over the next few years but never beat the Ranger, which eventually ran a quick 13.9 at just on 100mph.
The Fordies tried over the years…but never got there. We had an open challenge to Ford and a 12 second ET plan if they did manage to be competitive. We even clobbered their stock Capri Perana V8’s
The point of this story though hinges on what happened next. With Jim having returned to the ‘States, we lost our support base and whilst we kept our portion of the deal under wraps we naively miscalculated the reality of corporate politics. I had the starry eyed notion that as a successful Trainee project which was entirely self-generated in terms of the tech application ( we did everything ourselves with absolutely no help from our so called more learned engineering colleagues) this would be a feather in our caps….Not so.
After that second ¼ mile run and just before a week-end I was told that the car would have to be given to the Dealer “because GM is not in racing” and we should prepare for that, as the collection would take place that Saturday. I assumed, wrongly, that our involvement would continue in assisting Hunts, the dealer concerned. I had planned a complete development programme for the car, which included a 260 Bhp 3 Litre four (based on the 181 cubic inch version of the same engine) and a reduction in mass of about 100 Kg. The target was to crack a 12 second ¼, again at absolutely minimal expense, as most of the required bits were in house.
Just how trusting and stupid can one be. What had really happened is that our Engineering colleagues were seriously pissed off that we had shown them up and it was they who came through to collect the car that day, taken it to engineering, removed the engine and run it on the engine dyno. I had good friends in Engineering who regaled this story to us on the Monday…there was just one sweetener. Our engine produced 30 Bhp more than the best 2.7 litre fours run by them, had a fatter torque curve and bhp peaked 400 rpm lower. The engine was stripped to see what we had done and put in a box for the dealer to reassemble. This event was strike one for me with the engineers but also a black mark for me with one particular individual who ran the Test and development area. Man was I naïve!!!
The Witteklip ¼ mile venue. This pic gives a good idea of the venue and the atmosphere and is significant to the story in that it was the first event after the Ranger had been ‘stolen’ from us and one of the few events in which I did not compete. I had trashed my sedan road car a few months before and decided instead to put my energies into organising the event. That purposeful looking dude strolling across just to right of the MG is me. The station wagon Kadett on the left is my ‘new’ road car, the back end filled with timing equipment. The MG is Eldred Bischoff’s 327 Chevy engined machine, a very neat package able to run very consistent mid 12’s despite initially running a three speed ‘box!
As luck would have it, the person allocated to run the car by the dealer was also a friend, Ashley Benn…that took some of the sting out of the situation and so we assisted in getting the package together properly for him…. and we left it there. The car ran consistent low 14’s for the next 3 years, won the class every time….until Karma intervened beautifully in September of 1974.
See part two next week.
It was 2am and there was this knock at my flat door…..Ashley standing there seriously under the weather…… “Paul we’re in shit……..”
-Hullo Paul. Amazing recall and your part in the Ranger! The Ranger detail styling car stood on the floor in front of me for me to look at every day! Glad you refer to the Product Engineering Building! The windowless building was a nightmare when the lights failed! You could not see your hand in front of your face! I see your refer to the Vauxhall Victor grill! I knew it as the Vauxhall 2000 grill. With regard to some of the engineers upstairs agree with you! Some great guys and some kick in the Ass jerks!
With regard to diff ratios! Can you expand on the 3.08, 3.45, 3.7 and 4.1 diff’s please! My 3.7 diff is amazing but no upper end speed!
Hi Johan I guess you know who I was referring to as Jo in Part Two??
The diff ratios you quote are from the smaller Borg Warner Axle used in the Chevy L4 powered cars Firenza/Ranger. The Model 75 as it was known then and subsequently the model 78 fitted to the sixes,V8’s and Can Am. Ratios for the bigger axle are 2.92, 3.23, 3.5, 3.7 and 4.0 and the reason I chose it, as noted was that they had a cone Limited Slip unit used at the time on V8 Perana and Can Am.
The Gearbox was brilliant. You will remember the Nomad, that had the Commodore box with stock ratios ,tough as nails with big bearings. The close ratio box used the same casing with 2.72, 1.68, 1.3. and 1:1 ratios. The only mod required to fit it was to machine a larger bearing cavity into the ext housing casing.
Great to get the background on that old Ranger
Brilliant piece of history. I have just bought 2 x Rangers off an uncle in Somerset East. I am an avid GM, more Opel fan and couldn’t believe my luck when I found a RWD, 2 door, Old school “Opel” Coupe.
Dewald I am looking for my dad’s lost ranger. It was a white coupe with blue and gold striping across the bonner and down the sides. If you happen to see one somewhere please email me at ronnievanrensburg@gmail.com. Thanks