Ruling The Streets With An L88 Big-Block Nova

It’s October 1969. Larry Moore and his best friend are seniors in high school. Together, they head down to Tom White Chevrolet in Corsicana, Texas to each place orders for their own, nearly identical 1970 SS396 big-block Nova.

Ordering A Big-Block Nova In 1969

As they worked through the order forms, there were choices to be made, but there were some non-negotiables. Under each car’s hood would be a 396 cubic-inch, 350 horsepower engine with a close-ratio, four-speed Muncie transmission, and 3.31 gears bringing up the rear. Of course, the 396/375 HP option was a strong contender, but neither was too enthused about the need for valve adjustments at the time. The only real difference between the new Novas was that Larry’s car was black, and had Positraction and Rally wheels. His buddy’s big-block Nova was blue with no Posi (his dad said he didn’t need it) with blue wheels and hub caps. Both came with bench seats and AM/8-track player radios.

Initially, the duo was quoted approximately $3,800 to get each car out the dealership’s door. With some shopping around, they found dealers willing to deliver the same cars for around $3,100 apiece. The young wheeler/dealers then managed to get the original dealership to match that price. Larry put down $1,100 and financed $2,000 with a $68 monthly payment.

The original warranty paperwork with the Protect-O-Plate is still on board! An AM/8-Track player with Jimi Hendrix makes for some vintage gear jammin'!

The Life Of A Typical Big-Block Nova

As often happened, Larry’s car was modified and used hard, and eventually, it got sold, making way for other hot rods. But, the other big-block Nova was only driven for four years. It had Positraction installed before being parked, as there was a brief plan to put it on the drag strip full-time. A new LS6 454 cubic-inch engine was assembled from the GM parts bin and a Pro Stock-style scoop was grafted to the original hood. This project was short-lived, as its owner decided the engine would be more fun in a jet boat. The original 396 went to another friend for his ’68 Camaro, and sadly, a few rods exited the block after one too many 7,000-rpm shifts.

On the streets, the front SS emblem was removed to not give away what was about to happen at the next light. It was too late when they noticed the 427 on the fender and the final view from the rear would look like this.

Larry kept up with the Nova over the years as it languished in his friend’s backyard. Finally, in 1984 he managed to bring it home, but it still needed an engine. As luck would have it, word came down about a genuine (yet wounded) L88 427 being available. It was in a ’67 Camaro with a four-speed and 4.56 gears that was owned by a fellow who didn’t quite understand the fuel needs of a 12:1 compression ratio race engine. The first time he hammered the bearings out of it, GM fixed it for him under warranty. The next time he was on his own and decided he wanted out. The whole engine, carburetor to oil pan was snagged for $300!

The Beast Appears — The L88

Any GM-based L88 already includes the good stuff. Forged 12:1 pistons, forged rods with 7/16-inch bolts, steel crankshaft, four-bolt mains, rectangular port heads, and a serious, solid, flat-tappet cam. Larry knew what he had and took pains to make it right. A new crankshaft and rod from the Chevy parts counter were delivered to Jimmy Atkinson Racing Engines in Waco, Texas. The rotating assembly was balanced and the short-block clearances were meticulously blueprinted to ensure power and longevity.

L88 engine in 1970 Chevy Nova

High-RPM power with reliability is achieved with simplicity. No roller cam, no roller rockers, no aluminum heads, no fuel injection, no boost. Just good ‘old-fashioned American horsepower!

Pump-Gas Big-Block Power

Much thought was put into improving the engine’s streetability as well as its power. First, a set of iron, rectangular port, and open-chamber (vs. closed-chamber) cylinder heads were installed. This dropped the compression ratio closer to 11:1, allowing the engine to operate on 93 octane pump gas. The other big change was a larger, solid flat-tappet camshaft from Competition Cams. Combined with the factory 7/16-inch pushrods and long-slot, stamped rocker arms, you have a bulletproof valvetrain. A Moroso oil pan and high-volume oil pump round out the package.

Validating what GM’s engineers and Mr. Atkinson created is the fact this engine still runs perfectly after all these years. A diet of Valvoline VR-1 40-weight oil has kept the need for valve adjustments to near nothing. The valvetrain worries that kept the 396/375 HP engine off the original order list turned out to be unfounded.

The Big-Block Nova Gets Day-Two Mods

An L88 on the dragstrip would typically have 4.56, 4.88, or even 5.13 rear gears. But on the street, you’ll never get it to hook up. Larry runs 4.10s in the original 12-bolt rearend to give it a chance at gaining traction. This also allows some “roll-ons” when the desire hits. Other mods over the years include Mickey Thompson headers, Lakewood slapper bars, tow bar tabs, a Hays clutch with a Lakewood scatter shield, a Hurst shifter, re-arched rear springs, a full complement of Stewart Warner gauges, and Cragar Super Trick wheels.

The Hurst Super Shifter (with a handle from a forklift) has been working the gears all this time (right). Simple traction bars (center), coupled with re-arched leaf springs take care of traction duties. The exhaust still wears the "Turbo" mufflers installed 30-plus years ago and Stewart Warner gauges in direct view (right) keep tabs on things under the hood. The original 12-bolt housing contains 4.10 gears on a GM Positraction unit.

Putting It To The Test

Its first shakedown pass was at a Green Valley Race City Super Chevy Show. Larry managed a 12.06 quarter-mile E.T. in the sweltering heat. The too-tall 9×29-inch slicks stuffed under the fenders combined with the close-ratio transmission and 4.10 gears proved terrible for a good launch, but the car was a rocket once moving. Larry crossed the finish line in third gear! Later track excursions proved the deep 11-second capability of this pump-gas street ride. Easily enough to rule the streets back in the day.

An L88-powered big-block Nova was a surprise to anything that pulled up beside it on the street or strip. Designed to make power in the upper-RPM ranges, it took a driver who wasn't afraid to use ALL of the tachometer and let it get to work.

Experiments ensued using the Holley 800 cfm double-pumper carburetor on an ancient Edelbrock “twisted” Tarantula intake manifold against GM’s L88-style, dual-plane intake. With the center plenum divider removed, the dual-plane worked best on the street and let it wail on the top end.

Carburetion is handled by a Holley 800 cfm double-pumper. Ignition is just as simple, an ACCEL ball-bearing-style dual-point distributor firing through Moroso "Blue Max" plug wires. This is 7,500-plus-rpm equipment. No electronics are necessary.

L88 History Lives On

These days, Larry drives the Nova at least weekly. This isn’t a recreated “Day Two” car put together from an internet shopping list. Nope, it’s the real deal with mods to make it faster when it is being used as intended. The big-block Nova made local history and earned it the hard way. Larry straddles whether to restore the car or preserve its history. Currently, the L88’s history lives on, continuing the legacy it created during a simpler time when a hot rod served as your daily driver, Saturday-night racer, and all-around cruiser with your buddies.

L88-powered Chevy Nova

About the author

Jim Moore

Jim Moore built his first engine at the age of 14 and later became an ASE Master Technician. You can often find him cruising the street in his 8-second, twin-turbocharged, 1967 Corvette with a documented top speed of 200 mph in the standing mile.
Read My Articles