1960 Australian Modern Motor road test of the Miller Motors ID conversion

THE vital statistics of Citroen’s “Goddess” are known to everyone who has the slightest interest in motor cars.
But did you know there’s a shapely lady of this brand around Melbourne that can nudge l00 m.p.h. in top gear and do a genuine 90 in third, with her engine turning at 6000 r.p.m.?
She’s a real hot number, this one.
Miller Motors, Melbourne agents for Citroen, cooked up the modifications on the car~—an ID-19 model- after studying an English conversion of the type often used by rally entrants in Europe.
They reckoned they could do better - and do it at less cost, too.
This is what they did:

• Raised compression from 7.5 to 1 to 8.5 to 1 by shaving the head;

• Ported and polished the head;

• Fitted a Lucas sports coil;

• Fitted cooler KLG F100 plugs;

• Replaced the standard Solex carburettor with a twin-choke Weber;

• Modified the exhaust system to lower back-pressure (no estimate of b.h.p. available, but I can tell you there was plenty).

Total cost of “mods” was about £140. The results are practically as startling as an English Connaught conversion that costs £156 sterling.

Romping Performance
Now, I like to bring back my test cars in one piece. I was told the’2-litre engine would happily rev to 6250 r.p.m., when valve bounce would stop it spinning faster——believe it or not, the valve springs were standard.
I decided to limit engine speeds to 5750 r.p.m., just to be on the safe side.
This could be the ideal figure, too.
I made a run up to 6250 in third, and there didn’t seem to be any useful increase in torque after 5750.
The gear-change points then worked out at 35 m.p.h. in first, 65 in second and 91 in third.
True maximum speed in top was 98.6 m.p.h., with 101 coming up on the best one-way run.
The most impressive acceleration figure was 0-80 m.p.h., which the Citroen disposed of willingly in less than half-a-minute.
Top and third gear maximums are so close because the upper gear in the standard car is an overdrive ratio, designed to hold a high cruising speed on suitable roads. In any sort of traffic, third is used all the time.
You might imagine that the Miller-Citroen was a bit fierce to drive.Citroen was a bit fierce to drive.
Actually - and this is the greatest tribute to the efficiency of the conversion—-it was a lot smoother than standard.
And there was a good deal of extra punch in the middle-speed ranges that cut out the need for a lot of gear-changing.
On the acceleration runs the engine never missed a beat, and the water temperature stayed steady. The car used neither oil nor water.
Over 5000 r.p.m., though, the engine sounded as busy as a swarm of bees. The exhaust, which pokes out at the side of the car just in front of the nearside front wheel, let you know all about how you were you know all about how you were treating the engine, too.
Can’t say I thought much of putting it there, either. Everyone I passed must have got a lungful of my exhaust fumes.
But cruising at around 90 in top gear was quite restful. This worked out at 4600 r.p.m., accounting for fairly well-worn tyres.
Mechanical and exhaust noise were not uncomfortable at that speed - and the beautiful aerodynamics of the body cut wind noise to a whisper.
I’ve always been surprised at the 90 m.p.h. top speed of a standard ID-19, considering it has less than 70 b.h.p. for test weights of around 24 cwt. One of the factors I'd never taken into account, together with the front-wheel drive cutting out long propeller-shaft horsepower losses, is that the bottom of the body forms a smooth undertray.
This would be worth at least two or three extra m.p.h. at about 90.
I found the hot lady was a bit rough on premium petrol, so I spiked it with 20 percent Benzol. This cocktail was very much to her liking.

Handling Unimpaired

The only driving techniques peculiar to front-wheel-drive cars are:

• You must pull them through corners by using the accelerator all the way for best and safest results.

• You must let in the clutch and then turn on the power: let it in with a bang on 3000 revs or so, and the torque reaction lifts the nose and spoils wheel adhesion. Also, the short transmission is so rigid that it is brutal to crown wheel and pinion.

Forgive my ignorance, but I had never come across a hot Citroen before. I’d always regarded it as a most unlikely job for such attention.
But when you consider that its oil-and-air all-independent suspension, disc brakes, steering and aerodynamics are - taken all together - the most efficient and understressed combination in any production car yet built . . . well, why not?
Understeer is pronounced, which means that, despite the pull-the-nose-round effect of front-wheel drive, the steering gets tiresomely heavy when cornering flat-out for mile after mile.
But at low speeds it felt lighter than any Citroen’s (sic) I’ve yet driven.
I used 18lb. of air in the big, baggy Michelin X front tyres for maximum adhesion, and 20lb. in the back to cut down friction and make it possible to place the tail exactly where required on a corner.
But apart from all the fun I had out of driving this car, the thing that rocked me was the fuel consumption.
On the test track it was 20.6 m.p.g.; and over 200 miles of open-road cruising as fast as conditions allowed, this car returned 30.2 m.p.g.!
One point-to-point average over 68 miles was 61 m.p.h. That’s where good aerodynamics and good engineering really pay off.
I make no predictions about longevity. Generally, with any hot car, the more you use the extra performance, the sooner you pay for it.
I will say, though, that our test car was a trade-in that had done 17,000 miles — 15,000 of them in standard form. It did not seem to mind being belted at all.
The Miller mods made a good touring car even better-faster, smoother and easier on petrol when driven sanely. If you can really he trusted with a hot car, you’d get a lot of fun out of this £140 worth.