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Hot Rod Magazine Labeled the LS6 Chevelle "Earth Mover". To understand the "Pinnacle" You have to realize just what a monster the LS6 Chevelle was.

Nothing can Compare to 1970 when it came to factory supported horsepower wars - period.
1970 - Screaming the loudest before you die!

by the Wild About Cars Staff - reprint with permission only

In the six short years since 1964, the US automobile industry was on a performance stampede. It seemed like every manufacturer (including American Motors) jumped on the performance bandwagon with both feet. Every year, one or more manufacturers tried to "one-up' the competition. Let's do a brief recap of the goings on that lead to the "Big Bang" year of 1970.

1965 – All GM divisions now had 400 cid engines in their mid-sized bodies. Chevy released the 396 cid "Rat motor". Ford tried to qualify their Single Over Head Cam (SOHC) Hemi version of their 427 in NASCAR, and when rebuffed, handed it over to the drag racers. NASCAR banned the Plymouth Hemi in 1965. Funny Cars were born with the altered wheelbase Dodges and Mustangs.

1966 -  Oldsmobile put a three two-barrel set up on their 442's, Ford and Mercury brought out the re-designed mid-sized Fairlane/Comet with a 390 cid V8 and late in the year added optional 427 power to the fairlane. Chrysler released (unleashed?) the 426 "street Hemi" in Dodge and Plymouth. Mercury had several fiberglass one piece Comet bodies made to drop on tube chassis with supercharged SOHC engines – the funny car term "flopper" was born. The Chrysler Hemi was allowed to return to NASCAR. The SCCA (Sports Car Club of America) launched the Trans-Am series for cars under 2.0 liters and for those cars over 2.0 liters. Ford's Mustangs with 289 power immediately dominated the over 2.0 liter series.

1967 – GM released the Camaro and Firebird as competitor to the Mustang. Mercury releases the Cougar as an upscale Mustang. The Camaro had the 396 as an option and the Firebird had a 400 cu .in. engine. Camaro scooped the Pony car boys with a special 302 cid version of the Chevy small block called "option Z28". It was introduced specifically to to qualify for the Trans-am series. The L88 aluminum head version of the 427 Chevy is installed in Corvettes. Ford updates the Mustang and offers a version with 390 cid power. Ford Makes the 427 available in the Fairlane so as to qualify it for NASCAR. Richard Petty with Chrysler Hemi power dominates NASCAR with 27 wins.

1968 -  Ford introduces the 428 Cobra Jet engine for street and drags. The engine is available in the newly redesigned Fairlane (Torino), Mustang, Comet and Cougar. The fastback Ford and Mercury mid-sized cars show a distinct aerodynamic advantage in NASCAR super speedway competition. David Pearson wins the NASCAR championship for Ford, driving for Holman-Moody. The Camaro Z/28 is released as a separate model.  American Motors jumps into the fray with the Javelin and AMX. Dodge redesigns the Charger and Plymouth introduces the Roadrunner - both to rave reviews.

1969 – The "aero wars" of NASCAR begins with the Ford's Torino Talladega and Mercury's Super Cyclone sloped nosed cars – Chrysler counters with the Charger 500 (not so good) and the famous winged Charger Daytona. Ford introduces the Boss 429 "semi-hemi" in the Mustang and makes enough cars to qualify it for NASCAR competition in Torinos and Mercury Cyclones. All Ford/Mercury cars in NASCAR run this engine. Dodge releases the "440 six-pak" in the Super Bee. Ford releases the Boss 302 with its unique cylinder heads for SCCA Trans-am racing. AMC teams up with Hurst to build 390 cid powered cars (using the AMC Rogue) called the SC/Rambler. They are painted a patriotic red white and blue.

1970 – The high water mark! Given the frenzied activities in the performance market, every manufacturer was determined to release the very best offering of power and performance . The "Win on Sunday – sell on Monday" mantra was sung by all.

  • NASCAR – It was bare knuckles on the Grand National circuit. Chrysler released its winged Plymouth Superbird (a version of the 1969 Dodge Daytona) to lure Richard Petty back to the fold. He had raced a Ford in 1969 to protest the lack of a competitive Plymouth. Ford was using last year's Torino Talladegas and Mercury Super Cyclones. At the beginning of the year, each team used the largest engines from the manufacturers – Ford/Mercury teams used the boss 429 and Chrysler teams used the legendary 426 Hemi.  This would be the final season of full factory backing.
  • SCCA – The Trans-Am series had become enormously popular. Featuring "pony cars" with engines restricted to 5 liters (302 cu.in.) the series had given rise to the Camaro Z/28 and Ford Boss 302. In 1970, Chrysler introduced their newest "pony cars" – the Dodge Challenger and the Plymouth ‘Cuda. Not to be denied, each offered a special small block version to qualify for the Trans-am series - the Challenger "T/A" and the "AAR" 'Cuda . In Chrysler's case, their "street versions" had the 340 cu .in. Chrysler LA engines with triple carburetors. American Motors hired Roger Penske (previously the winner of the 1968 and 69 Trans-Am Championship with Camaros) to field their Javelin entry. In spite of all the competition, Ford would win the Championship in 1970 with their Boss 302s.
  • NHRA/AHRA – In late 1969, AHRA introduced a "Pro-Stock" category. This top stock class featured the elimination of handicap starts and permitted wide latitude in engine/body style configuration, and in 1970 the NHRA adopted this class. The Pro-Stock Class in 1970 was all "big motors". Immediately the class was filled with 427/454 cid Camaros, Hemi Challengers and ‘Cudas, Ford SOHC Mavericks and Mustangs.
    1970 also saw the high water mark of the front engine nitro burning top fuel dragster. A transmission explosion blew apart Don Garlits dragster and seriously injured him. While recovering, he designed (and introduced in 1971) the rear engine fueler. 1970 was the last year these front engine cars were dominate in top fuel.

The manufacturers pulled out all the stops in 1970.  An individual seeking to buy a performance car was like the proverbial "kid in a candy store". Here's what was available – in general terms – from just about every manufacturer.

  • Big block "supercars" – these had engines of at least 426 cid. GM expanded their engines to 455 cid in mid-sized cars. All "pony cars" now featured a big block option topping 400 cid.
  • "Junior supercars" these were small block engine mid-size cars - using engines between 340 – 351 cid in mid-sized cars and "pony cars".
    Trans-Am qualifiers – the Mustang Boss 302, the Camaro Z28, the Challenger T/A, the AAR ‘Cuda, The Mark Donohue Javelin.

An when it came to big blocks - it was madness:

GM - For the first time, GM allowed divisions to install and sell mid-sized cars with engines larger than 400 cid Each division responded:

  • Chevrolet installed their 454 Rat motor in the Chevelle and Corvette. In Chevelle, option LS6 was a 450 HP monster Hot Rod Magazine called it an "Earth mover".
  • Pontiac punched out their 400 engine to 455 for the GTO and added a 400 inch Ram Air V.
  • Oldsmobile put their big 455 cu. in engine in the 442 and with the famous W30 option.
  • Buick – added their 455 cid big block  and released it with the Stage 1 option, a car capable of running with anything on the street or track.

Chrysler -

  • Chrysler offered the 426 Hemi and 440 Magnum V8 with three two-barrel carbs on GTXs Road Runners, Chargers and Super Bees.
  • In a move that not only caught up to their rival "pony cars" but surpassed them – Chrysler offered the 440 6-pack and 426 Hemi in the Challenger and ‘Cuda lines. Both cars became legends.

Ford - In addition to the Boss 429 Mustang and 428 Cobra Jet Mustangs, Ford released a new engine family – the 385 series – at 429 cid in their mid-sized line. The hottest 429 was the Super Cobra Jet - available in Torino and Comet at 370 HP.

American Motors - AMC placed their 401 cid engine in their mid-sized car and (with another outrageous red/white/blue paint scheme) and called it the "Machine"

Screaming small blocks – the Junior Supercars. By 1970, the insurance industry was leveling stiff surcharges on cars that they felt were over-powered - all of the supercars from every manufacturer. To offer the buyer a performance orientated car that would not be subject to insurance surcharges, most manufacturers created strong running small block cars that not only performed well but handled better than their larger and heavier engined brothers.

GM had two divisions that had a focus on screaming small blocks – Chevrolet and Oldsmobile.

  • Chevrolet – in 1970, Chevy released the 350 cu .in. LT1 small block option in Novas, Chevelles, Camaros and Corvettes. This engine had 11.0:1 compression, solid lifter camshaft and a big 4 bbl Holley carb. It was rated at 360 HP and could run! When fitted to the light-weight Nova, this combination was a street/track monster. Many a big block would fall to LT1 Novas.
  • Oldsmobile - Olds had the Cutlass W31 – this was the final year for this small block wonder. In 1970, their 350 cid engine received an aluminum intake manifold along with the W25 OAI hood scoop option. The W31 was deliberately under-rated at 325 HP (the standard Olds 350 was rated at 310 HP) The engine had the famous Olds "308" camshaft, 455 big block valves, 11.5:1 compression and could rpm to well over 6,000 rpm with ease.
  • Ford - released the 351 "Cleveland" engine. This engine differed from the 351 "Windsor" engine in that it had canted valve heads like the Boss 302 and the 396/427/454 Chevy big block and it sported big valves and ports. It had 11.0:1 compression and was another high-revving "deep breather" that could be had in the Mustang and Torino lines.
  • Chrysler - Dodge and Plymouth put the 340 LA engine in the new Dodge Dart and Plymouth Duster. Both of these cars featured the same 340 cid engine previously available in the 'Cuda and Dodge Dart GT. Rated at 275 HP, these small blocks were vastly under rated and in these cars, that weighed in at around 3200 lbs, made them very quick.

Special Performance programs from the manufacturers: The manufacturers always had performance options available. Rear end gear ratios, camshafts, special intake systems and the like. But in 1970, each manufacturer "packaged" and heavily promoted these options in special marketing brochures and programs.

  • Dodge had the "Scat City Scat Pack Club" which had special packaged options from "show" to "go"
  • Plymouth offered  the "Rapid Transit System" that mirrored Dodge.
  • Ford had their Ford Performance Buyer's Digest – which listed recommended options from cams, to heads, to multiple carb systems. This was a marketing package - started in 1969 - a take off of the previous "Total Performance" program.
  • Each GM line had special performance Brochures, with Olds and Pontiac leading the way with detailed packages. "Dr. Oldsmobile" became the picture of performance for Oldsmobile "W-Machines".

1970 was most certainly the peak year of the classic "muscle car" as we know them today. But this would also frame their sudden plunge from the automotive scene.

In 1971, leaded gasoline was beginning to  be removed from the US economy due to health concerns. Unleaded gasoline had much lower Octane rating than leaded gas and those high compression (10.0:1 or higher) ratios that helped generate the powerful horsepower figures were no longer feasible. GM dropped all their engines to less than 9.0:1 in 1971. By 1973, Ford and Chrysler had followed suit.

But the most crippling factor was the surcharges on Muscle cars set by the insurance industry.

When combined with the need to comply with the newly mandated exhaust emission standards, there was no way big inch engines could make the stupendous HP of 1970. Thus, the horsepower wars stopped so fast that a few years later many wondered if they had ever occurred.

Thus, safety laws made the cars heavier, "smog" laws crippled horsepower, insurance companies tripled policy costs for high hp cars - there was no way the manufacturers could deal with all this. Yes, there were still 442s, GTOs, SS396s, GS Buicks, Ford Boss 351s and even Hemis for a few years after 1970, but by 1976 they were all gone - completely gone.

So the classic muscle car died much faster than it had risen to prominence. But they went out "screaming" and we'll never forget that. We would not see "light and the end of the tunnel" until the mid-eighties . .  But that is for another chapter.

Packing just as much punch as the LS6 was the 426 Hemi, shown here in the 1970 Plymouth 'Cuda. It gave away some cubes, but not HP.

Even AMC got into the act with their Rebel "Machine". It was limited to 390 cubes, but because the car was light - it could motor. It sure looked the part!

Ford's Torino 429 SCJ was equipped with the Factory's new "385" block sporting canted valve heads similar to the Chevy LS6. It gave away a few inches at 429, but it had plenty of punch!

Pontiac put their maximum performance in the 400 cid block - and it handled itself very well.

Dodge heavily hyped their "Scat City - Scat Pack" in 1970

Even Mercury was in the big muscle - with their Cyclone 429.

A Buick GS Stage 1 surprised many - it was quicker than most.

Mustang's Boss 302 took the SCCA Trans Am Championship in 1970

Oldsmobile's W-Machines were lead by the W-30: 455 inches of get 'er done.

The Camaro was late to the party in 1970, but it came loaded. The new Z/28 now had 350 cid LT-1 power.

Meanwhile Dan Gurney was prepping Mopars to do battle in Trans Am.

Dodge Challenger was new on the scene - but it had all the good stuff!

440 Six Barrels or Six Packs abounded in Mopar land including the Dodge Super Bee

Corvette packed 454 power, but surprisingly the LS7 which was to be the ultimate 454, never materialized.

AMC touted Mark Donohue's AMC Javelin effort.