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Suspension Tuning

If you are tempted to play around with the suspension on your 33, here are a few pointers supplied by Derek Pickard.





A 33 is not only a sweet all-round car with a really different engine, it can also be the basis of a fast handling road or reasonable trackster. The basis is there - all it takes is the knowledge of how to make it turn.

When first released, the Alfa Romeo 33 on the surface looked a typical 1980s FWD compromise car with only the flat four engine making it stand out from the crowd. But when looking beneath the surface, deeper into the chassis, was a layout far superior to what other makers were producing. The basis is good and the potential is excellent.

Handling-wise there are three generations of 33. The first were basic but by the time the 1.7ti arrived it was lower and stiffer which improved cornering considerably without too much of a sacrifice in comfort. But while Alfa were developing their small sedan, so were the Japanese. In fact when the 33 was languishing with just a 1.5 single cam engine in the mid-1980s, Japanese makers like Toyota had dealt an ace card with the Corolla 1600 twin cam 16 valve that boasted good handling to match the excellent power. The hot hatch competition had gone global.

Alfa reacted to this and quickly boosted development of the final 33 which not only saw a twin cam 16 valve top end put onto the 1.7 engine but the revised body had improvements in the handling and ride. It also featured a simplified rear linkage layout. The Alfa engineers had learnt how to refine the lower and harder suspension arrangement to retain reasonable comfort. But these last 33s were also the heaviest (nearly 975kg) and so inevitably had the best ride.

Now, letšs put handling performance into perspective. While the first 33 was a reasonably good car in many ways, its heritage is nothing less than excellent. The best fun car Išve ever built was a Sud ti 2 door with a 33 1.7ti engine. That thing had the lot: relative light weight, sensible component layout (central petrol tank etc), great suspension and steering configurations, good (for a FWD) weight distribution, big brakes and a really nice torquey engine. Not only did I have a ball running it around town for a couple of years but with a few tweaks the car won its class in the local Alfa club championship against more powerful RWD machinery.

But the 33 is not a Sud ti. The 33 1.5 is heavier (the series one is around 950kgs instead of the Sud tišs 880), puts more weight on the front axle (67% instead of 63), has one or two better suspension and steering changes but various regrettable compromises. (The numbers I quote are the result of my own measurements. I earn my living as a motoring writer and rarely trust makersš figures.)

On the good side, the designers gave the 33 a bit more steering castor and front neg camber with straighter front links and no sway bar. But that all came at the cost of slightly smaller front discs, outboard front brakes, rear drums and a smaller rear lateral control rod. Like I said, wešre dealing with compromise.

Now for a dose of reality: In stock form the overall package of ride comfort and road noise to handling is a reasonable all round set-up and quite acceptable. Also, most people who spend heaps on expensive brand Whambang exotic suspension units with 36 adjustments fail to realise they will be running one of the 35 wrong settings. Chassis tuning is a demanding skill which very few have. Most think it is no more than going for a suspension which is low and rock hard.......they are wrong.

(In brief, tuning in and out a characteristic like understeer or oversteer is essentially the ability to arrange an imbalance in the behaviour of the front to rear settings such as spring/damping rates, sway bar, etc in conjunction with fine tweaks to the alignments of all 4 wheels and their tyre pressures. A simplification would be to state that the front likes to sway on harder pressure and the back should remain flatter on less pressure to achieve more of a neutral handling. Oversteer is possible but not recommended.)

Fitting larger diameter alloy wheels with low profile tyres usually has these effects:
  1. The owner is poorer.
  2. The car can appear more fashionable.
  3. The steering will be sharper but heavier at low speeds.
  4. No number four
  5. The ride comfort is worse.
  6. The increase in tyre roar noise forces the radio to be turned louder.


So spending the money on bigger wheels and tyres starts a driver going down the road of compromise where some good points are traded at cost for some bad. There is no magic in auto engineering and only the owner/driver can decide what is value and which is preferred.

Lowering a car has some similar effects. It can make the 33 look better and give sharper turning. But the ride comfort will deteriorate and road speed humps can cause expensive bashes on the sump and exhaust system. (The last 33 1.7ti I bought had been accidentally speed humped with the bashed up sump practically sealing the oil pump pick-up which then destroyed the engine. Be warned.)

A 33 can be lowered by one of these methods:
  1. Fill the interior with bricks (only practical for sales photography).
  2. Removing the springs and cutting off a coil or two. But the rear springs can then fall out of their retainers when the car is jacked to replace a punctured tyre.
  3. Give the springs to a capable spring specialist who can professionally lower them.
  4. Buying properly made lowering springs.
  5. See number four.


Providing the spring rate is not increased too much, good condition stock Alfa shocks will prove adequate for just about all road use. But for those with money to spend who insist on buying something like Spax or Koni adjustable dampers, DONT tighten their adjustments too much - the car will ride and handle worse. For example, Koni yellow gas shocks are tight enough at the stock setting.

The most common and understandable mistake for beginners to make with modifying suspension is to fit overly hard shockers. This gives the effect of the car bouncing along the road on its shocks. That is the worst of both worlds - bad handling and bad comfort. Full efficiency means the car has to ride on its springs which must work with suitable damping from the shocks. A car with a suspension movement which works for the application has better ride and handling than a car with rock hard suspension.

The most useless mods from beginners are usually:
  1. ultra small steering wheel
  2. overly low/rock hard suspension
  3. wide tyres on narrow rims.
  4. No number four.


The combination of 205/50x15 tyres on 15x6 alloy wheels with slightly lowered tighter suspension will transform the behaviour of the car. For those who live in areas of smooth roads with enjoyable bends, it will feel like a true little sports car, but that will be at a financial cost and the comfort will be worse.

There are one or two short cuts to help cancel out some of the understeer by quickly stiffening the rear. The easiest way is to replace the stock 33 back springs with factory upgraded ones. If your model has the stock 11.2 or 11.5mm spring wire diameter springs then look for a pair of 11.8 replacements from the station wagon. But if these are not available then improvise by making a pair of spring coil clamps. These are no more than spacer locks which clamp one or two coils at a fixed distance to stop them compressing (or stretching) under load. Some suspension modification specialists used to make such components and you might be able to locate a pair that can fit; but it may be quicker just to prefabricate a system. Be careful to measure the required setting with the car sat on all four wheels level - that is the distance between the coils which must be maintained by a clamping system. And donšt clamp more than two coils as the change will be too abrupt. This method can also be used to effect slight alterations in ride height.

The next step of arranging an anti-sway bar is a lot harder. A suitable bar with its fittings has to be found and then the rear end must be modified to take the layout. Be careful to choose one from a car of not only the same suspension width but also a very similar weight. I recommend starting to look at the various small Japanese hatches as many of those were fitted with anti-sway bars front and rear. If a torsional adjustment cannot be arranged then it may be neccessary to find options on bar diameter. Generally speaking, itšs best to start with a relatively thin one as such a change does have a noticeable effect.

As regards suspension and steering mechanical alignment settings, it helps firstly to understand the benefits of the stock performance. And to achieve that, all the caršs bushings must be in excellent condition before any work is done. There are plenty of them and all must be thoroughly checked.

Another basic must is the matching of the tyres with their pressures. In stock form the compromised recommendations are for comfort so raising the pressures around 5psi will quicken the steering and sharpen the handling. But keep the difference of front to rear. Properly done, a small amount of oversteer and understeer tuning can be achieved this way.

The most important stock car mechanical setting is the front toe. This is another compromise and the maker advises around 2mm toe-out which may be hard to achieve as the only way of varying it is to turn the steering joint on a thread which only allows coarse variations. Išve found it should be no more than 1mm and there is not much point is going above 3mm for most road applications. 4 or more is strictly for applications which include quick tyre wear. Itšs your money.

(One of the tweaks I used on the Sud when arriving for a club day at the race track was to detach a steering link before rotating it out a full turn to go from about 2 to 4mm toe. This would slightly improve the cornering and help keep heat in the tyres. But it could also slow the car on the faster circuits, so the road setting was left alone.)

Very little on the mechanical side can be easily reset without much work. For example, it is possible to incorporate an adjustment for length into the front links that can pull a bit more castor into the steering, some rubber bushes can be replaced with harder polyurethane bushes to advantage, the front hub mounting system system can be modified to introduce more negative camber, the rear hub flanges can be shimmed to achieve both negative camber and positive toe. And an adjustable rear sway bar should be fitted before a front anti-sway bar. All these can improve the caršs handling at the limit.

There are a couple of easy mods for early cars such as fitting the slightly lower and stiffer 1.7ti units to a stock 1.5. But quick and cheap bolt-on examples are rare. Virtually nothing as simple can be done to the 16 valve cars.

The reality though, is that nearly all of the modified facilities are only of advantage to racing cars. For fast road stuff, an owner is really going up the graph of diminishing returns. Most road drivers will appreciate little more than a good set of tyres set to suitable pressures, slightly stiffer road shocks, totally checked overall alignment and maybe slightly stiffer and lower road springs. The next step is bigger and lower tyres on larger wheels. As for going further than that, itšs mostly fantasy or racing.