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Alfa Romeo GTV6 and Fiat 600

     This photo is an Alfa Romeo postcard. This is a 1986 GTV6. It can be recognized as a post 83' car because of its larger front Alfa Romeo emblem, low side moldings, and wheels that were available on the GTV6 in 1986 only. The 86' cars are considered to be the best and most desirable GTV6s however the truth is they are all pretty good and the early cars have some advantages. The later cars have a few more advantages but not enough to justify a large difference in price.  Don't pass up a really great 82' for a mediocre 86'.

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     The Alfa Romeo GTV6 was produced from 1981 through 1986. There are rumors of some 1980 cars and some 1987 cars but I doubt you will ever see one, at least not in the U.S. The differences from year to year are fairly minor but I will try to touch on the bigger ones.

     The GTV6 was arguably the hottest and best sport coupe of the early 80's. It features a 2.5 liter V6, four wheel disk brakes, inboard at the rear, and a rear mounted transaxle to give near perfect weight distribution. It has a great racing history, having won just about every championship it was eligible for. Usually cars with a great racing history and low production numbers become quite valuable. Somehow though it seems these cars have been largely forgotten and thus are quite inexpensive. If you want a fun collectable car this just might be not only the best buy out there, but also the best car!

     Almost all GTV6s left the factory with Alfa's fantastic 2.5 liter V6. A few cars sold in the South African market had a 3.0 liter engine of the same design and in the U.S. a twin turbo version was available in later years with about 50% more power but it is ultra rare. This engine has two cams, five main bearings, a wet sleeve design, hemi heads, Bosch fuel injection and about the strongest crankshaft I have ever seen this side of an American V8. This engine has 154 horsepower. That may not sound like a lot of power now but compared to it's competitors of the day it was a monster! The Porsche 924, Mazda RX7, and BMW 320i all had about 100 horsepower, the 1982 Z28 and Trans Ams had 145, the 280Z which was considered the really hot car in the early 80s had 140. The Alfa's motor enabled it to outrun nearly all of its competitors and reach a top speed on 130 mph, this was at a time when the most common police car the Dodge St. Regis has a top speed of 90mph and took over two miles of road to reach it. The Alfa is not made for the stoplight grand prix, but it's actually pretty good at it. One magazine got a 0-60 mph time of 7.6! I think that was a really cold day with a really great driver and maybe even a cheater car. However the GTV6 is certainly capable of low to mid eights.

     The Alfa V6 uses one camshaft in each head. It actuates the intake valves directly and the exhaust valves via a very short pushrod and rocker arrangement. This arrangement is very clever because it allows very high RPM without the danger of a thrown or bent pushrod but with the bearing drag of only one cam per head. Only a few engines in history have used this short pushrod trick, one was a Mercedes sponsored Indy Car engine that won the Indy 500 a few years ago. In stock form the engine is in mild tune with fairly low compression and mild cams plus the engine is very strong with a great crankshaft and a very stiff block and heads. This means its power can be increase easily and without fear of destroying the motor. Alfa actually provides instructions for boosting its power output to over 200 hp. With turbo or supercharging its power levels can reach incredible heights, 300, 400 and even 500 horsepower can be attained.

Here is a brand new GTV6 2.5 liter V6.

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     The GTV6's suspension is second to none. The rear suspension is a Alfa's De Dion type which is quite unusual. Only a handful of cars have ever used this type of suspension including the Gullwing Mercedes some Lancias, at least one world championship wining Formula 1 car and some Lotus'. The Alfa De Dion setup is basically a big triangle with wheels mounted at two corners and the front of the triangle mounted to the chassis via a really large bushing. There are many advantages of this setup. First of all suspension travel has no effect on rear wheel alignment, none, zero. Just about every other type of rear suspension has a geometric effect when it moves causing the wheels have camber changes and or toe changes during suspension compression and rebound. With this setup the rear wheels never loose their relationship with the road no matter what the road or driver does (well short of driving off a cliff). Since there are no geometric changes associated with suspension travel the designers of the GTV6 were free to include as much suspension travel as they could fit in the space available, thus the GTV6 has more rear suspension travel then any other car I know of and it rides well because the designers did not need to use really stiff springs to keep the rear wheels pointed the right way during cornering. Another often forgotten advantage of the Alfa De Dion set up is that the wheels provide thrust to the center of the car. Remember all cars transmit power from an engine to a transmission then to the drive wheels and finally through the suspension to the car. It's the suspension that the drive wheels push or pull on. In any other type of suspension the power is delivered asymmetrically to the car. In other words when one wheel bites better then the other during acceleration normal cars apply more power to one side then the other. That's why some cars tend to get a little unsettled when you hit the gas at low speed or coming out of a corner. This is not a factor in the GTV6, no matter which wheel is biting all the power is transmitted to the center of the car and it will go straight as long as the wheels are not slipping.

     To further exploit the De Dion's characteristics, Alfa located the rear shocks upside down and the rear disk brakes inboard at the transaxle. This plus the use of alloy wheels reduces the unsprung weight to a minimum thus allowing the rear suspension to react to inputs from the driver or irregularities in the road very quickly.

    The Alfa transaxle is located within the perimeter of the De Dion triangle. This rear mounted clutch and transaxle provide excellent weight distribution, officially it's 50/50! The list of cars using front engines and rear mounted transaxles reads like a who's who of performance car history. This list includes the Porsche 928, Ferrari's current top production car the 550/575 and the latest generation of Corvette. Ferrari's top Formula One driver claims this is the best setup for a road car, even superior to mid engine.

     The front suspension of the GTV6 is a variation of the classic twin A frame design common on serious performance cars. Just about every great performance car has used this type of front suspension but the Alfa made theirs a little better then most by using forged lower A arms riding on bearings, not bushings and a threaded rod to provide adjustable castor. Camber adjustment is made using shims.

Another factory photo showing a brand new rear suspension, transaxle inboard rear brakes, and clutch housing.

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     Ok Ok, enough technical stuff, so how well did all this fancy engineering really work you might ask. Well according the automotive press at the time, very very well. In a Road and Track comparison test the non turbo GTV6 came out way ahead of the Turbo 280ZX and Porsche 924 Turbo. They didn't even factor in the GTV6's advantage of having a usable back seat, something the other two cars did not have. Motor Manual said when comparing the 83' GTV6  to the Mitsubishi Starion Turbo, Datsun 280ZX, Mazda RX7, BMW 323i, and Honda Prelude Si that all may be fine cars but "none have the breeding, prestige or balls-out performance of the GTV6." What Car? magazine compared the 82' GTV6 to the Toyota Supra and Mitsubishi Sapporo Turbo. They were too wishy washy to declare any one car the winner but the Alfa out ran the other cars and got better fuel economy while doing it.

     Only one car fared well against the GTV6 in comparison tests and that was the European market only Ford Capri 2.8i which was built in Germany but tuned by Ford's Special Vehicle Engineering operation in England. The British magazines tend to favor their home vehicles and the Capri 2.8i was their baby so in most subjective tests they said it was a better car. On paper both cars had identical performance, the Alfa achieved its through design, the Ford by using simple car just souped up to a higher state of tune by Ford's SVE dept.

     Someone at Car magazine, another British publication decided to test the two cars together at Castle Combe which is apparently some famous race track in England. Although the numbers suggested they would be close the Alfa easily defeated the Capri on the racetrack. They still ended the article saying the Capri was the better car for entirely subjective reasons.

     There were three points of criticism of the GTV6 common in the automotive press which I feel I should address. First there was a lot of complaining about body roll. The car always seemed to get around the corners faster then it's competitors it just leaned a lot doing in and the journalists did not like that. What they apparently did not understand is that the Alfa's suspension allows the wheels to remain upright and in good contact with the road even with a lot of body lean. Lesser cars don't have suspensions that allow that so they limit a car's body roll by stiffening the suspension and sacrificing ride quality. Alfa did not need to do that.

     The second point had to do with driving position. Most journalists felt that the steering wheel is located too far away from the driver if the seat is adjusted to be the proper distance from the pedals. Again, they don't really understand the car. In the U.S. most drivers are taught to hold the steering wheel at the 10 and 2 o'clock position. In Italy they hold the wheel at the 4 and 8 o'clock position as did most Formula 1 drivers at the time (they now have a different type of steering wheel in most F1 cars that can only be held at 3 and 9). Grab the wheel at 4 and 8 and it will feel like it's at the right distance. Grab it at 10 and 2 and it will be too far because of the way the steering wheel tilts. Drive the car like an Italian and you will feel very comfortable in a short time. As a point of interest Alfa did move the steering wheel closer to the driver in the GTV6's later years but no one seemed to notice. It still was not close enough for the 10 and 2 grab anyway.

     The third point of criticism involved the shift linkage. This is actually a valid criticism until Alfa improved the linkage in mid 85 but the early linkage can be greatly improved with a couple hours work and about five dollars. There is a bushing in the shift linkage made out of plastic. It wears out quickly causing the shift linkage to become sloppy. It's easy to replace with a metal bushing and that will make the linkage just fine. I plan to explain just how to do this on page 3. They also complained about the Alfa's poor transmission syncros and this is a fair criticism but with proper shifting technique the syncros will last a long long time, over 100,000 miles. If you think you know how to shift, and maybe you do but read my article on double clutching anyway, I will be adding it to page 3.

     If you are considering a special interest car the GTV6 is one of the best. You can find driveable early examples for as little as $2,000, and $4,000 buys you a great one and 7,000 a near perfect car. If you are a big spender you could buy one of the very rare Callaway Twin Turbo models and enjoy its 230 hp and six second 0-60 times for about $8,000 for one that need some help up to about $15,000 for a great one.

     Some say that the later GTV6s are much better then the early ones, that is not really true. They are all quite similar. All years have the exact same bodies. Side molding, emblems and available colors changed but the cars all look the same. The 82' and 83' cars have fairly tall gearing, not as good at the race track or when zooming away from a stoplight but superior on long highway trips. The 82' and 83' cars are about a half second slower 0-60 mph but are quieter at highway speeds and use less fuel. A well tuned 82' or 83' car will get 32 mpg at 70 mph with no problem! The other years will only get about 28 mpg at that speed and can get just over 30 mph if driven at 55 mph. The 1984 and later cars have no fresh air vents, they were replaced with a more powerful air-conditioning system called Tropic Air. The air conditioning in early cars can be improved to be as good as the Tropic Air systems so that's not really an advantage. The Tropic Air system also took up the space occupied by a little shelf on the 83' and earlier cars. That shelf is nice to have for holding CDs and stuff. The 81' through 83' cars have their front ends up a little higher then the 84' through 86' cars however they are all too high and any GTV6 should be lowered to the European front ride height. Lowering is accomplished via an adjustment involving the torsion bars, no new parts are needed. The mid 85's and all the 86's have an improved shift linkage but it's only a little better that a modified early linkage. The later linkage also has a lot more parts to wear out, it's quite complex and it makes changing the clutch a real pain, instead of the relatively easy job it is in the early cars.

    In short the later cars have some minor advantages but they are not enough to justify passing up a good early example.

This GTV6 is an 83' it is can be recognized as a pre 84' car because it has the smaller front emblem. This particular car is quite fast with an estimated 165hp. It's also lowered and has polyurethane bushings throughout its suspension. The intake louvers and hood center are normally dark Grey but the owner of this one has decided to brighten things up a bit. This is the same year and color combination as the GTV6 James Bond used to outrun the BMW cop cars and save Europe from a nuclear disaster.

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Here is a factory photo of an 85' car. It has wheels that were available in 85' only. This car appears to be a European spec car because it's front end is not up at the U.S. ride height. If you have a GTV6 the front end should be lowered to match the car in this photo. White GTV6s are very rare, it's too bad since I think they look nice.

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ALL GTV6s came with high quality alloy wheels. This is a Campagnolo wheel like the ones all GTV6s came with until 1985. This type of wheel was sometimes colored black or white from the factory but most look pretty much like this one. It is the strongest and best of the stock GTV6 wheels. The 1985 car came with  nice looking wheels made by Speedline, but they are an odd size. The 1985 wheels have a 365mm diameter instead of the 15" diameter all the others have. This makes it very difficult and expensive to buy tires for them and impossible to buy modern tires. Most owners of 85' cars change to the 15" wheels from other years. The 1986 car had 15" wheels also made by Speedline but they are not quite as high quality as they original Campagnolos.

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Here is my 66' Fiat 600.

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      The Fiat 600 was introduced in 1955 and Fiat continued production until 1969. Other manufactures produced the 600 under license well into the 1970s. It's a simple car, with the engine, transaxle and radiator located in the rear. It has a primitive but clever four wheel independent suspension and weights about 1330 pounds. The early cars have a 633cc liquid cooled 4 cyl motor producing 22hp. There was a minivan version called the Multipla which could seat 7 people making it arguably the worlds first minivan. There were numerous performance versions by Carlo Abarth who was a sort of Carol Shelby of Italy. The various Abarth versions had tremendous performance for their time with the earlier models having 52hp and the hottest ones having well over 110hp. Perhaps the most famous version was the 850TC which had 68hp from its 847cc motor. The Abarths as well as regular 600s that were souped up had a very successful racing career but were ultimately banned by the SCCA for reasons I have yet to discover.

      My Fiat 600 is a 1966 "D" model. This means it came with the larger 767cc 29 horsepower engine and its doors are hinged at the front. Many of the earlier years had suicide doors hinged at the back. The "D" model's bigger motor gave it enough power to outrun many of it's arch enemies including the 1200cc V.W. Beetle as well as some 850cc British cars. My 600 is modified although not so much that the car looses any of it's original character.

     The body of my car is unlike other 600s. Each of its fenders and quarter panels are flared out about 1.5 inches. The flares are metal and are done so well they are very hard to see. Only people very familiar with 600s can tell the fenders are not the way they were when the car left the factory. The paint job in the colors of the Italian flag really draws attention. The structure on the front houses a custom radiator.

     My car is powered by a Fiat 903cc motor. I wanted a 903 not just because it would have more power but because it's the historically correct motor for a hot Fiat 600. A 903 powered Fiat 600 is very rare today, in fact this is the only one I know of. I have heard quite a few owners claim their 600s have a 903s but everyone I have checked has turned out to be powered by something else. If you are buying one of these cars, especially via an auction it would be wise to have a knowledgeable person inspect it before paying a premium for a supposed 903 car. The 903 is basically the same design as the original motor, however installing it is a major pain. Although the motor is the same design there are a number of serious complications in this swap some of which are nearly insurmountable. First of all the engine rotates the wrong way for the 600's transaxle. This means if you bolt the engine in and go you will find all of your forward gears move the car backwards and only in reverse can you move the car forward. Obviously this is not acceptable and the motor needs to be made to run in the opposite direction. Getting the motor to run the other way involves a cam change and some oil seals. Yes that's right, oil seals are directional and if you have the wrong ones installed the engine will force oil out as fast as you can put it in. There are other problems too which are much more serious. The biggest of which is that not a single water pump made will bolt onto and actually pump coolant on a reverse rotation 903. Same thing with the starter. To solve these problems you must get some parts from some cars that were never sold in the U.S. and have quite a bit of custom work done to make them fit. Next there is the clutch problem. The 600s stock clutch will not handle a strong 903 so custom work is needed again. Cooling the 903 is a problem too. The 600s stock radiator is too small and no matter how big a radiator you put in the stock location it can't do the job because there is no way to get enough airflow through it.. Abarth solved this by mounting a front radiator. The Abarth front radiator kits are obtainable and I had one. The problem with it is that no commonly available fan will fit in it, in fact no fan I could find would fit. So although it might work fine on a racetrack which was its intended use, it's not much good when stuck in traffic. To solve this problem I simply had my own front radiator and housing made and designed it to handle any possible cooling needs. There are many other complications involved in installing a 903 that I can't even begin to touch on without using a lot of space.

     Most fast 600s run either a souped up 767cc motor from a D model or an Autobianchi 1050cc engine. The souped up 767 is preferable to the 1050 since it's authentic, and  period correct. It's also a whole lot easier to set up and it will not require a front mounted radiator. The 1050cc should be avoided because it's historically incorrect for the car and will reduce its value. It produced 60-70 horsepower which is about what you can get out of a 903 but it does not sound as good or rev as freely. The 1050 motor is however a lot easier to install then the 903 because it rotates the same way as the 600's original motor. However you still have all the other complications involved in setting up a 903. In short if you want a fast 600, get a 767cc motor and soup it up. If you have plenty of time and patience, plus some fabricating ability go for the 903.

Notice the engine cover is ajar. That's not just for looks or cooling. The 903cc motor is taller then the stock 600 motor so the cover can not close all the way and a latch must be made to hold it in this position. If the engine cover closes all the way then the motor is almost certainly not a 903!

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     In addition to all the work required to use a 903 in a 600 I did a little extra. My 903 is souped up to about 70 horsepower. There is nothing exotic here, just normal improvements, higher compression, big carburator, hot cam, and free flow exhaust. The car is fairly quick now, and because of its small size it feels really quick. In fact it feels quicker then my Alfa GTV6 although actually it's not even close. The motor idles smooth at 1000 rpm and pull hard from only 2000 up to 8000! That's about the widest powerband of any engine I have ever driven. It's very exciting to rev it up through the gears. It has reached 94 mph at about 7500 rpm in fourth and it still had more! At 94 mph it seems like you are going about mach one.

     To help cornering and braking I installed Fiat 13 inch wheels with Yokahama A008 tires. The tires are 175/50s and fit in my larger than standard wheel well perfectly. I like Fiat's steel wheels because they have a nice offset and are very high quality. In modern traffic good braking is a must and the 600's stock brakes are just not up to the task. In 1962 they were good but now that car in front of you probably has 4 wheel vented disks with anti lock so to be safe the brakes must be upgraded. To do this I upgraded the front brakes to disks. A 1300 pound car with good disk brakes and sticky tires can really stop, which is obviously important in modern traffic, especially in a small car. I did not change the rear brakes to disks for a couple reasons. First of all it does not need it, the front disks really do a good job. Second the 13" wheels will not fit into the 600's spare tire well. In fact the stock 12" wheel barely fits with the skinniest tire I could buy. This means that if you have a 600 with four wheel disks your spare tire will have to go in the backseat. That's not acceptable because the stock spare tire location in the front of the trunk is intended to help weight distribution and crash protection, both of these are things I did not want to sacrifice. Plus I like having a useable backseat. Of course there is always a complication. The 12" spare tire will not fit over the disk brakes. That means if I get a flat front tire I have to put a rear tire in its place and put the spare on the rear. No big deal though, and I keep good tires on the car and I doubt I will ever get a flat.

The 600's interior is very comfortable for such a small car. It seats four adults easily, a six foot tall 200 pound man can fit in the backseat! Luggage space is provided in the forward trunk and behind the rear seat. Few cars are more fun to drive then a fast Fiat 600 or draw more attention. Any fuel stop in this car draws a crowd.

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This picture was taken at Hallet motor speedway. That's my wife driving and my friend JR providing instruction. I only let this car run in touring class since we don't want to push the car too hard. My wife drove in the first session of the day and really took it easy, leaving the car in fourth the whole way around and not taking corners aggressively fearing the antique swing arm rear suspension would cause the car to roll over. The next session my dad drove the car and in the ten minute session was only passed once, and that was  by a Pantera. Although the other cars in the group were not driving at the limit, this shows that a well set up and well driven 600 can still at least keep up with more modern cars. Plus unlike some of the newer cars there it never overheated its engine or brakes, and never quit running or failed in any way. In fact this car has never left me stranded, I put it together with a lot of thought and consideration and have been rewarded with a very reliable car!

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