We had one in the family, sandy colour with orange stripes. Visited Aunt iin Washington State once and Mr. know it all neighbour couldn't believe his eyes, to him it was a Vega but was he ever shocked to see Pontiac on it!

1974

The GT's look kind of neat...

I kinda like the little Pontiac "ashtrays" as we used to call them. Had a close friend who had a V8 Vega in the mid 80's. What a fast ride for the street.... It destroyed the rearend every single time you would pull a full throttle shift with the 4 speed. We learned very quickly to shift it nicely or walk. Guess the stock diff wasn't made for 350hp.

Sure is rare to see a stock Vega or Astre on the streets now. Used to see them quite a bit in the 80's. They rusted out in the pillars and the roof for the most part.

Ask 64 lemans about Astres! He was beat out by a original low mile car and it was a bad green. His car is a 64 lemans 4spd with a 10000.00 paint job. I think the car show was rigged. Not to bash the Astres because all Pontiacs are king but Ricks car is really nice.

I think these cars would be fun with a turbo Buick 3.8. Why haven't I seen one yet?

Yup,my brother in law had a little Blue Ashtray too.

I had a '74 Vegamatic. Before it finally died, it was blowing so much oil it wasn't funny.

timbuk wrote:

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i think they had aluminum blocks that expanded when they got hot,thus rings could not seal

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The Vega's engine was an all-new SOHC inline-four. It was big for the economy-car class, at 140 cu. in. (2.3 L), and somewhat undersquare, with a 3.50-in (89 mm) bore and 3.63-in (92 mm) stroke, for good low-end torque. As GM had promised, the Vega's engine did indeed have an aluminum cylinder block, largely at Ed Cole's insistence.

Aluminum is popular for automotive engines because it is significantly lighter than cast iron. It's more expensive, however, and it is softer, which presents a problem for engine blocks. Unlike cast-iron blocks, you can't run the pistons in a bare aluminum cylinder without causing rapid wear of the cylinder walls. For many years, the solution was to add iron cylinder liners, which works, but raises assembly cost even further.

In the mid-sixties, GM's Engineering Staff and Reynolds Aluminum developed new aluminum alloy called A390, with a high silicon content. If properly finished, it allowed a much harder cylinder bore surface, durable enough to allow the engine block to run without cylinder liners. Cole was very enthusiastic about this process, which he thought would be cheaper and simpler to assemble than engines with iron liners. (It's unclear if it actually was or not; GM said it saved $8 per engine, but John DeLorean later claimed that it cost more than iron sleeves.)

There was nothing conceptually wrong with the Vega's linerless A390 cylinder block. The block wasn't strong enough for serious racing use, but it was adequate for street use, and, despite some early casting problems, bore wear was normally very low. Indeed, linerless aluminum blocks are very common today, with few problems. The engine's problems began with its cylinder head, which for cost reasons was not aluminum, but cast iron. Aluminum-head/iron-block engines were common in those days, but the reverse was very unusual. The Vega's iron cylinder head actually weighed more than the block, making the engine somewhat top-heavy.

Among their differences, aluminum and iron have very different expansion rates, and their heat-conduction characteristics are totally different. As a result, if the engine overheated, it tended to warp the head gasket -- which mates the head to the block -- and then the aluminum. In the Vega engine, severe overheating also broke down the silicon of the A390 alloy, leaving a soft aluminum bore surface that would scuff easily.

As long as the engine remained within normal operating temperatures, this was rarely a problem, but the cost-cutting binge had left the Vega with an undersized cooling system that was barely adequate for normal use. Worse, there was no coolant-expansion tank (more cost cutting), so if the engine did begin to boil over, it also lost coolant, and would eventually run itself dry. That was bad news under severe conditions, like climbing mountain grades on a hot summer day, and it meant that any cooling system failure (a bad radiator cap or failed thermostat, for instance) could be fatal in short order.

Compounding this problem was the engine's tendency to high oil consumption. The culprit here was not usually the block, but the valve stem seals, which tended to be brittle, causing them to leak oil into the cylinders. The engine's propensity to run low on both oil and coolant did nothing to help its vulnerability to overheating.

Beyond that, the engine was simply not a very pleasant companion. It had adequate power -- 90 gross horsepower (67 kW) with a single-throat carburetor and 110 hp (82 kW) in optional L11 two-barrel form -- but it was disturbingly noisy when revved, and quite rough. Four-cylinder inline engines have an unbalanced coupling force, which causes the engine to rock up and down. The bigger the displacement (in particular, the longer the piston stroke), the greater the shake. Modern fours generally quell these forces with twin counter-rotating balance shafts, but that technology was in its infancy when the Vega was designed. Chevy settled for using very soft engine mounts, to isolate the shaking from the passenger compartment.

The soft mounts caused yet another problem. The magnitude of the engine's shaking was enough to gradually loosen the mounting bolts for the carburetor body, occasionally causing bursts of raw fuel to spray into the cylinders, producing dramatic backfires in the hot muffler. This problem eventually led to an expensive and embarrassing recall campaign, which cost Chevrolet both money and credibility.
 

 

-- Edited by Pontiacanada on Friday 13th of August 2010 06:05:17 PM

Here's a couple in the Ontario:

1974 Pontiac Astre SWEET RIDE!

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View larger image   Date Listed 10-Jul-10 Last Edited 09-Aug-10 Price $4,800.00 Address Perkinsfield, ON L0L 2J0, Canada View map For Sale By Owner Make Pontiac Model Other Year 1974 Kilometers 18000 Body Type Coupe (2 door) Transmission Automatic Colour Black Drivetrain Rear-wheel drive (RWD) Fuel Type Gasoline 1974 Pontiac Astre 355 V-8 automatic B & M 2800 stall black with gold Z28 stripe racing bucket seats American racing wheels hood scoop aluminum rad gold valve covers air cleaner B & M shifter Call Tim 705-526-2199

That's great Todd! Just how I might have built a Vega or Astre. 3.8L Turbo Buick engine with an automatic. I might have stuck with the Buick's 200 4R rather than a TH350 but it still would be a blast as is.

The torque of the turbo Buick engine is absolutely amazing. That little car would launch hard compared to 3800lb regal. (If you can get it to hook up)