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1965-'68 RPO L79 327 Engine - Performance Nostalgia

The 1965-'68 RPO L79 327

By Doug Marion, Photography by Doug Marion

Thanks to the L79 camshaft's hydraulic lifters, the engine stayed in tune just about forever. Spark plugs never carbon-fouled, either. Besides summer drag racing, my forte was engine super-tuning. I made as much money in one day of engine tuning as I did in one week of my summer job. Another 10 hp could be unleashed by quickening the distributor timing's rate-of-advance. The Holley carb's secondary diaphragm was almost always too strong. This meant the secondaries did not open until around 4,000-4,400 rpm. We either replaced the stock secondary spring with the weakest Holley spring available, or we just over-rode the system by installing a screw in the secondary linkage. Right in the middle of the linkage row was perfect for 3,000 rpm. This really made the L79 come to life. If tube headers were added, carb jetting was always necessary. I've known a lot of guys over the years who got away from high-performance because they installed go-fast goodies, but their car was not much quicker. Why not? They did not super-tune the engine (richen the carb jetting or install a larger carb, quicken the distributor advance curve, lower the coolant temperature, etc).

A friend from back in the mid-'60s, the late Jim Borecki, special-ordered a brand-new silver-blue Malibu SS with an L79 327, a Muncie close-ratio four-speed transmission, a 3.31:1 Positraction 12-bolt differential, factory chrome wheels and tubular headers (they came in the trunk). He installed the headers but left the engine in factory-tune (no super-tune). At Great Lakes Dragaway, Union Grove, Wisconsin, Jim waded through the D/Stock class competition one weekend running 13.80s at 102 mph. He crossed the finish line in third-gear! In the class final, he snoozed on the starting line and lost to a 13.90 e.t. '65 442 Olds. Ironically, a high school classmate's '64 3x2, 389 GTO with 4.33s also ran 13.90. Borecki's street machine clearly had 13.50 e.t. potential with simple engine and chassis tuning.

1966 L79 Production & History
A total of 7,591 Corvettes were ordered with the L79 327 out of 27,720 total production. The engine offered great overall driveability with zero tuning woes, and depending on the gear ratio, offered pretty fair, 15-18 mpg fuel economy too. The big noise and best bang for the buck for 1966 was the newly styled Chevy II with an L79 engine and the new SS 396 Chevelle. L79 Chevy II sales were 5,481. Car number 116376W162834 was my personal red-on-red sport coupe, which I special-ordered in late February at my place of employment, Nickey Chevrolet, in Chicago, Illinois. The car is still around today, but not as an L79.

The weak link on a '66 L79 Chevy II was the rear mono-leaf springs. They caused the standard 6.95-15 tires to wheel-hop on launch. As tire size increased, so did the wheelhop. A pair of new S&S traction bars and some Air Lift Air Bags from Nickey's speed shop run by Dick Harrell and managed by Al Gartzman cured the problem. My car ran 13.40 at 104 mph with the S&S traction bars, S&S tri-Y headers, 3.73:1 gears and M&H 9.00-15 slicks. It ran 12.70s at 107 mph with the addition of an electric fuel pump, hood scoop and a bunch of super-tuning. It was undefeated in class C-4 (C/Stock, four-barrel carb and hydraulic cam). Most weekends there were 10 to 20 1966 327 Chevy IIs in the class. The bulk of them were stock L79s. There were also a few 383 Mopars and 389 GTOs. The L79 Chevy II power-to-weight ratio was right at the top of the class.

I was in good standing with some of the Grand Spaulding Dodge guys via bench racing at Skip's Drive-In on North Avenue in Chicago and from the Sunday drags. Try as they may, no Street Hemi could get past my Chevy II or an L79 sedan owned by Al Gartzman. Mr. Norm's Grand Spaulding Dodge heard about it and an L79 versus Street Hemi contest was set up for Skokie, Illinois. Al and his L79 won three in a row. Both cars were brand-new and untouched. Mr. Norm's brother Lenny, drove the Coronet. Lenny had wanted to bet big bucks, but none of us had any money. The Grand Spaulding Mopar guys were always a hoot.

The only Chevelle that could challenge an L79 Chevy II was the RPO L78, 375hp 396. The 396 engine was a few hundred pounds heavier and the car was also heavier too. But the L78 396 engine revved to 6,500 rpm and its four-link rear coil spring suspension did not wheelhop. It was a runner. A total of 3,099 were sold.

By Doug Marion
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3 comments
sbacritchley
sbacritchley

i have a 1966 327 out of a Corvette i just bought in a old hot rod it has a aftermarket intake with no breather and valve covers with no breathers or pcv valve the breather at the back of the motor is plugged up i know this is not right i was told the cheapest way to fix this was to replace valve covers and put a breather on each valve cover is this the best way to fix my problem.

davekunes1
davekunes1

ihadanl79mali9buss#203couldanyonehappentoknowwhereitisnow.?isawitlastinmidd1970s

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