Friday, November 26, 2010

Hemi versus Fuelly



The January 2011 issue of my Classic Car Magazine has an interesting comparison, a fuel-injected 1957 Chevrolet Sport-Coupe versus a Hemi-powered 1956 Desoto (“hem-EEE;” not “hee-MEEE”).
The ’57 Chevrolet is the darling of the collector-car world, the car everyone wants.
They are so in demand, their prices are skyrocketing. ’57 convertibles sell for over $100,000.
What makes all the Tri-Chevys (1955-1957) so popular is their Small-Block V8 engine, introduced in the 1955 model-year at 265 cubic inches.
It was a revolutionary engine. It had a lightweight valve-gear that could be revved to the moon, 5-6-7,000 rpm, higher than anything else at the time.
The Small-Block became the desire of hot-rodders; cheap and available, and responsive to hot-rodding.
It retired the Flat-head Ford V8; flat-head because the engines were side-valve, like lawnmower engines.
Previously the Ford Flat-head had been the engine-of-choice among hot-rodders.
Lots of speed-equipment had been available for the Flat-head.
But the Small-Block skonked all that.
Fuel-injection in 1957 was mainly to give the Small-Block breathing ability.
It wasn’t electronically controlled, as most fuel-injections are now.
In fact, it was very rudimentary; about the same as the earliest vacuum-controlled fuel-injections installed on Volkswagen Rabbits in the ‘70s.
It was constant, much as the early F.I. Volkswagens were. —Rather than timed intermittently.
Fuel-charge delivery to each cylinder could be made equal. With carburetors the closest cylinders (e.g. center) ran rich, and the farthest cylinders ran lean.
Carburetion was messy and dirty, which is why everything now is fuel-injected.
The earliest fuel-injections on Chevrolets had long intake ram-tubes. Length was tuned to maximize charge intake — the air-column in the intake tube resonated.
283 cubic inches displacement, 283 horsepower. That’s one horsepower per cubic inch; phenomenal at that time.
But early fuel-injection was a beast — no one could work on it. It was beyond the comprehension of most mechanics.
Many F.I. cars were converted to carburetors.
The other supreme Detroit V8 was the Hemi; which means hemispherical combustion-chambers.
Normally all the valves in an engine, both intake and exhaust, were in a row parallel to the crankshaft.
The row could be canted toward the intake-manifold, but that tilted the exhausts in the wrong direction — that is, if the exhaust manifolds were on the opposite side of the cylinder-head.
But the Hemi turned engine-valving 90 degrees.
The intake valve could be aimed at the intake manifold, and the exhaust valves the opposite direction.
This required a hemispherically shaped combustion-chamber, what Chrysler called “FireDome.”
It also required two rocker-arm rods per cylinder-head — most engines only had one. —The Chevy Small-Block had none; ball-stud rockers.
Hemis were extraordinarily heavy; those monstrous cylinder-heads were cast-iron.
Three versions of the Hemi were brought to market.
#1) The earliest Hemis debuted in the 1951 model-year, and lasted through 1958.
They first debuted in Chryslers, but ended up in Desoto and even Dodge.
Chrysler gave up on the Hemi; it was too costly to manufacture.
But in the early ‘60s the NASCAR boys wanted a Hemi-head on the large displacement Mopar B-block, the so-called “Wedge” motor.
A Hemi breathed exceptionally well at high speed, generating gobs of horsepower.
#2) This led to iteration number-two, the so-called “elephant-motor.”
426 cubic-inches, hemispherical cylinder-heads.
Buddy Baker (at left) was the first to average over 200 mph for the world closed-course record.
This was done at Talladega Superspeedway in Alabama.
His car was a Hemi-powered Dodge Charger, although it was the wing car (the “Daytona”).
#3) Is the most recent “Hemi,” although to me this is just Chrysler Corporation cashing in on the earlier Hemi’s reputation.
Although it is a Hemi, and counters one of the early Hemi criticisms: incredible engine-weight.
Its cylinder-heads are cast-aluminum, instead of heavy cast-iron.
I don’t know about the engine-block.
To me, comparing a ’56 Desoto to a ’57 Chevy is comparing apples to oranges.
Attractive as it was, the ’57 Chevy was essentially basic transportation. The Desoto is more a road-cruiser.
And the Desoto Hemi is not the incredible Hemis of the 300 series Chryslers.
Seems they would have been more appropriate.
Richard Lentinello, head-honcho of the magazine, had an interesting opinion.
He panned the ’57 Chevy as “vulgar.”
I agree.
Better, in his opinion, was the ’55 Chevy.
I agree with that too.
In his humble opinion, the ’55 Two-Ten hardtop was the greatest of all the Tri-Chevys.
He even says the ’53 and ’54 Chevys were better-looking than the ’57; and to me they were turkeys.
The ’55 is the car I always dreamed of having throughout high-school, college, and even later.
Photo by BobbaLew.
The prettiest Tri-Chevy of all.
I have included an old photo (about 1961) of a ’55 Two-Ten hardtop, a really great car.
It started as a six, but the owner converted it to a 283 Small-Block with a floor-shifted four-speed Corvette tranny.
It really was fabulous, but he traded it for a ’58 Corvette, a mistake in my opinion.
The ’57 wasn’t bad. My parents had a few.
Two ’57 Chevys at the same time, both Bel Airs, one a four-door sedan, and one a four-door station-wagon.
The sedan was a PowerGlide six; even slower than our PowerGlide ’53 (also a six).
The wagon was a 283 Power-Pak; four-barrel carb, and dual exhausts.
I was smitten when we got it; our first car with a V8 engine, and a fabulous motor at that.
And they got it mostly as a second car for me. —The ’53 had failed inspection, and was junked.
Photo by BobbaLew.
Redemption.
WOW! The 283 Power-Pak Small-Block was a siren-song.
I’d drive home from work summers during college, all the windows down and back-glass up (as pictured), full-blast on the radio.
“Duke-Duke-Duke-Duke of Earl. Duke-Duke-Duke of Earl, Duke-Duke-Duke of Earl, Duke-Duke-Duke.......”
I used to wanna drag-race it; it was good for eighty in Lo, on the secret quarter-mile marked on Shipley Road in northern Delaware.
Its power was frightening, although I’m sure it would have been creamed on the drag-strip.
It broke loose when I tried to lay rubber — both rear tires!
It became the family car after I graduated college, which means my father never maintained it, and its silver paint blotched as silver paint often does.
In the photo above, the el-cheapo rim-protector tires are obvious. My father usually got used tires from a junkyard.
My father got a third ’57 later, a PowerGlide six two-door hardtop he hoped to restore.
But my mother made him sell it.
Photo by BobbaLew.
A ’55 business-coupe at Cecil County Drag-o-way in summer of ’65. (C/modified production is probably a 283 four-speed — that’s the owner-driver at right).
Comparing a ’57 Fuelly to a ’56 Desoto is a joke.
The Desoto comes off better.
Attractive as a ’57 Fuelly is, it’s more of a drag-racer.
Work on it after every blast down a quarter-mile drag-strip.
That’s work on it every 1320 feet.
Ya don’t get groceries in such a thing, or drive it 50-60 miles to the beach.
Driving such a car over highways would be fearsome.
What if it breaks down far from home?
You’re on your own.
A mechanic could fix a crippled Desoto.

• The Chevrolet “Small-Block” V8 was introduced at 265 cubic-inches displacement in the 1955 model-year. It continued production for years, first to 283 cubic inches, then 327, then 350. Other displacements were also manufactured. The Chevrolet “Big-Block” V8 was introduced in the 1965 model-year at 396 cubic-inches, and was unrelated to the Small-Block. It was made in various larger displacements: 402, 427 and 454 cubic inches. It’s still made as a truck-motor, but not installed in cars any more; although you can get it as a crate-motor, for self-installation.
• RE: “Side-valve....” —The cylinder-valves are beside, and parallel, to the cylinder-bore; i.e. down in the block. The top of the cylinder is covered by a flat casting (“Flat-head”).
• RE: “Constant” fuel-injection, versus fuel-injection “timed intermittently.....” —“Constant” fuel-injection provides a constantly pumped fuel flow to the injectors. “Intermittent” is tiny pulses of fuel to the injectors per timing.
• RE: “The exhaust manifolds were on the opposite side of the cylinder-head.......” is what is seen now, but the late ‘40s Cadillac flat-head V8 engines had the exhaust manifold on top, in the same location as the intake manifold. —It’s a nice idea, but it limits port size.
• In an engine with “ball-stud rockers,” the rocker-arms, which turn valve-actuation 180 or so degrees, and thereby make overhead valves operable with a central camshaft far away down in the engine-block, are not on a long shaft parallel to the crankshaft. Instead they are on individual ball-studs; studs with a ball on the end the rocker rocks around. (There is no rocker-shaft.) —Everyone went to ball-stud rockers after Chevrolet (and Pontiac, who developed them).
• “Mopar” is Chrysler’s parts division. The generic name for Chrysler Corporation is “Mopar.”
• RE: “Wedge motor......” —The B engine-block had wedge-shaped combustion-chambers, not hemispherical. Most engines had wedge-shaped combustion-chambers when overhead-valve (as opposed to flat-head).
• “Tranny” is transmission.
• “PowerGlide” was Chevrolet’s first automatic transmission. (Automatic transmissions were rather slow early on compared to a standard [shifted] transmission.) —PowerGlide had only two speeds: Lo and High.
• “Carb” is carburetor.
• “Drag-racing” is standing start-to-finish over a flat quarter-mile strip of level asphalt. Most street-cars could hit 80-120 mph or more. Dedicated dragsters were much faster, and were pushing 200 in the middle ‘60s when I attended. Now they’re over 300! —The drag-strip I went to was Cecil County Drag-o-way in northeastern MD, just south of DE. That drag-strip is now defunct.
• “Lay rubber” is to lay down a stripe of tire-rubber to the pavement from spinning drive-tires. The engine had to be powerful enough to break a tire (or tires) loose.

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