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Monday, February 09, 2015

Tenth vehicle - The 'Vette *Updated*

The tenth vehicle I owned was a 1971 Corvette.  What I really wanted was an old Jaguar.  I was pretty certain that a Jag would be expensive to own, unreliable, and difficult to find parts for.  So I decided to get a Corvette.  It was expensive to own, unreliable, and difficult to find parts for.

I traded my 1981 Z28 Camaro straight across for the 71 'vette.  The owner of the Corvette couldn't get the car certified for the California emissions "Smog Check", so he couldn't register it.  I, on the other hand, was in the military.  I could register the car in my home state and avoid the issue entirely.  Of course it would still be polluting the pristine California air, but it would be registered (and I would be paying licensing fees) in Idaho.  The trade was on...

*UPDATE* I found and scanned an old picture of the car:

The pokey old Z28 was gone, replaced by a Corvette with a big-block 454 cubic inch V8 with a 780 CFM Holley carburetor and a 4-speed Muncie transmission.  It also had independent rear suspension.  The engine was rated at 365 horsepower stock (which it was not).

The one redeeming feature of that Corvette:

The 'vette turned out to be an unreliable piece of crap, but it was brutally powerful, and it handled really well :)  There was so much *wrong* with that car that I had a list of stuff two pages long that needed to be corrected.  Sadly enough, I made that list long after I had fixed a bunch of other things and overhauled the engine.  To make this car right, it would have taken so much money that it would have been cheaper to purchase a different Corvette in good condition.

This is what the car *should* have looked like:

The car had been crashed at some point, the front end was a different style, having a later-model grille.  The new front end had also been damages slightly, with repairs made using Bondo dent filler up at the nose.  The replacement front end was probably from a 73 or 74, and the grilles were uglier than those of a 71.  The grilles were poorly installed, and one of them fell out and got damaged.  I ended up throwing both grilles in the trash.

This is the plain-jane front end my car had, lacking the cool '71 bumper or shiny grilles

The previous owner had installed flared fenders, added massive tires, and painted it with gel-coat, which is really soupy paint that is used on fiberglass boat hulls.  It looked pretty cool with the huge tires, although I actually prefer the stock look.

Below, a Corvette with flared fenders and very wide tires.

When I took possession of the Corvette, it had some awesome 4 inch side pipes on it.  I drove it for quite a while with those pipes, until I eventually ended up with a girlfriend, who kept burning herself on them.  In any event, they were starting to rust, as all exhaust systems eventually do.  I figured that if the exhaust system were going to rust, it would be best for that to happen under the car where no one would have to look at it.  I replaced the entire exhaust system, then I had to purchase the stainless steel side trim pieces to hide the bottom seam of the body (see the orange car in the third image).

The rear fiberglass of the 'vette had been modified too.  71 Corvettes have cool cut-outs with metal bezels for the exhaust pipes to exit the bodywork.  With side-pipes you don't need that, so these cut-outs had been filled in.  This is how it should have looked, but it didn't.

So far I have only discussed the car's basic appearance and what I didn't like about that.  There were also a plethora of mechanical issues that I worked through, and some that I never made it to.  I guess I should start at the front of the car.

The engine always had a miss, and I assumed that it was due to worn valve guides, a worn cam, or something to do with valves or compression.  As a result I decided to pull the engine and go through it.  What I learned was that the previous owner was an idiot.  Chevy Big-Block cylinder heads that were made for passenger cars have two types intake of ports:  The lower-performance oval port, and the larger high performance (but not very good for street use) square port designs.

Oval port:

Square port:

The Corvette had the oval-port cylinder heads.  While taking the engine apart, I was startled to find that the aftermarket intake manifold had square ports!  Stupid owner.  The inlet air was rushing down the huge square-port runners of the intake manifold, then hit the restriction of the oval port head.  The airflow *had* to experience quite a bit of turbulence where it hit the restriction.  You want the smoothest possible airflow into your engine, so somebody had screwed up, badly.

This was an unexpected cost to an already expensive rebuild...  I ditched the single-plane square port intake manifold for a dual-plane oval port manifold.  I also replaced the 780 CFM carburetor with a Holley 650 double pumper with a mechanical secondary.  The goal was to get away from high-rpm components, because it was a big block that wasn't even built for high RPM.

The Holley carbs were both a pain in the ass.  The old one leaked gas on the engine.  The new one leaked gas on the engine.  Both of them would get the float stuck and overflow gas on the engine.  They needed constant adjustment.  After owning two different models of Holley carburetors, I realized how awesome the Rochester Q-jet is.  It's nearly maintenance-free and rarely leaks or gets a stuck float bowl.

I went through that engine and didn't find anything else irregular, except that the rod bearings were .030 smaller than stock.  So the motor had been damaged at some point also.

Shortly after finishing the rebuild, after I had run the motor in, I found myself driving along near Seaworld, trapped behind a lot of cars that were moving way below the freeway speed.  I got really annoyed and impatient.  Another freeway lane opened up on the left, and nobody was getting into it.  I pulled over into the open lane and floored it.  The vette squatted down and the engine roared.

Immediately I heard a massive "thump" and saw parts come out from under the hood and go flying in the air overhead.  That wasn't very reassuring on a new motor rebuild.  Soon after that, steam started billowing out of the hood and blocking my view.

I pulled over and assessed the damage.  One of the motor mounts had failed, and the engine had lifted up on that side.  The radiator fan had hit the hood, cracking it open, and two fan blades had come off.  One of them punched a hole in the radiator (an expensive four-pass radiator), and the other fan blade had come out from under the car and gone flying overhead, caught in the wind.  It took a lot of time and money to get the car running again after that.

The car pulled hard to the right most of the time, unless you were accelerating, and then it went straight.  So depending on whether you were just going along, braking or accelerating, you had to make pretty big corrections in the steering.  I had always thought this veering around was due to front or rear wheel alignment, and I had the car aligned several times, with no improvement.  After several years of putting up with this, I finally figured out that it was the power steering pilot valve was out of adjustment, and just needed to be screwed in to a neutral point.

When I got the car it really handled poorly.  It was god-awful, and a real handful to control keep in a lane of traffic.  Part of that handling issue was the problem described above.  The other part of the problem was that it was riding on cheap-ass bias ply tires.  Bias Ply!!!  Eventually they wore out and I replaced them with pricey Goodyear radials, and the difference was amazing.  It was like going from a truck to a sports car.

The alternator caught on fire once, shortly after I replaced a different one that had simply quit working.  That was one of the few things the 'vette had in common with other GM models, so it didn't cost me a fortune to replace.

The transmission always crunched going into 4th gear.  The synchro was probably in the bottom of the Muncie.  I just double-clutched it like I was driving an old school bus when going into 4th.  It was one of the many problems that were just too minor to worry about on that car.

The rear window on some Corvette models was removable, and there was a little compartment to store it in.  Cool.  The rear window on my Corvette had been broken at some point, and the guy replaced it with a sheet of blue plexiglass.  Uncool.  I never got around to getting a piece of automotive glass for that.  It was so far down the list of things to do...  Things that kept the car running, for instance.

One night a buddy and I were headed down to Mission Beach when an ominous grinding sound came from the back of the car, and it stopped dead in the middle of the street.  I clutched it to keep the motor running, then had to really give it a hell of a lot of gas to move again.  I nursed it over to a parking spot using a lot of gas and clutch, as the rear end ground and popped.

I knew this was going to be bad.  I had it towed back to Sub Base until I had enough money to replace the guts of the rear end.   The ring had broken in the ring and pinion.  The positraction unit was also smoked.  That was a pretty expensive and long down-time event.  Since it was ruined, decided to replace the tall 3.08 gears with a lower 3.77 ratio for faster acceleration, which was not a good pick for a big block.  I probably should have gone with something in between, because at freeway speeds the big engine was running pretty fast.

At one point I had to rebuild the brakes, because they reached the point where I had to stop the car by pushing the brake pedal to the floor, and then stop the car by using the emergency brake.  The brakes were horribly complex.  Each brake caliper had four(!!!) cylinders and pistons that needed to be cleaned, honed, and repaired with parts from a kit.  The cylinders were so corroded that even after the rebuild, the brakes were still only so-so.  The aftermarket sells stainless steel sleeves that can be inserted in the cylinders, so I'm probably not the only one who had to deal with this issue.

The worst fuel mileage I ever got out of that car was 8 MPG, blasting up the road to Big Bear Lake.  The best fuel mileage I ever got was 13 MPG, gently cruising down the road from Big Bear Lake.  There have been times when I missed that car.  It really rocked when it was running.  But damn, it failed so often, so massively, and so expensively, that it wasn't very fun to own.

Inside view.  Just behind the shift lever is the engine nameplate data, with displacement, compression ratio, horsepower and torque ratings.

The car ended up gathering dust in the garage for a decade before I ended up selling it.

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