Five best muscle car street engines

[Eric]

Everyone has their own opinion about which muscle car engine was the best muscle car engine - because we each have our ideas about what it takes to be the best. For some, it's all about peak horsepower numbers - even if the engine was barely streetable. For others, it's about wild designs - canted valves, cross-ram intakes and multiple carbs (or fuel injection). But when the parameters are defined more closely - and the question is, which muscle car engines were also great street performance engines - the following contenders deserve a tip of the hat:

* 1970 Buick GS 455 Stage 1

Don't be misled by this engine's seemingly mild 360 horsepower rating - be thrown back in your sport bucket by its stupendous 510 ft-lbs. of torque - more torque than any other engine of the muscle car era and all of it available at just 2,800 RPM. And torque, not horspower, is what moves a street car (especially a two-ton muscle car) down the quarter mile like a scalded cat. In the case of Buick's 1970 GS, that would be a searing 13.8 seconds flat at more than 100 mph through the traps - and 0-60 in 6.5 seconds. Those numbers make the '70 GS Stage 1 455 one of the quickest factory stock muscle cars ever built, bar none. And it delivered that performance with air conditioning and power windows, through an automatic transmission - and with civility few similarly high-powered muscle cars of the era could hope to match. The Stage 1 engine featured a cold-air induction hood scoop/dual-snorkel air cleaner, high-flow Quadrajet four-barrel carb, large valve heads and a hotter camshaft, among other upgrades. It represented the pinnacle of Buick performance - and a record that would not be challenged until the mid-late '80s and the introduction of the turbocharged Regal Grand National and GNX.

* 1973-1974 Pontiac SD-455

The SD-455 is considered by some to be the last hurrah of the classic muscle car era - and that it was. Even when it was a brand-new engine, it stood virtually alone; Ford, Chrysler and even the rest of GM's divisions (including Chevrolet) had killed off most of their true performance engines - and even the cars that once housed them. The 290-310 horsepower (net) SD-455 Trans-Ams and Formula Firebirds were truly the last of the line. But they were also the most potent Pontiacs ever offered to the public - besting earlier bruisers like the 1970 Ram Air III 400 equipped GTO and the even more radical (and rare) Ram Air IV 400-equipped '70 Trans-Am. And they did it with low (8.2:1) compression, a fairly mild hydraulic cam - and radical round port heads that flowed more air than all the politicians in Congress combined. A stone stock SD-455 was capable of low 13 second quarter-mile runs and top speeds approaching 140 mph - with a non-overdrive three-speed THM400 automatic transmission (or non-overdrive 4-speed manual). Uncork the factory exhaust, shoe the thing with drag slicks and dial up the ignition timing a bit and SD-455 cars were reportedly high 12-second machines. That is fast by any standard - even today's. A new Corvette Z06 is only slightly quicker - and it is advertised as having more than 500 horsepower and has the benefit of a modern six-speed gearbox and massive tires to hook it all up. One wonders what the true output of the '73-74 SD-455 really was. And how fast it might have been with a bit more development - and better tires to put all that grunt to the pavement instead of brutalizing the overmatched 15-inch rubber that came on the cars of that time.

* 1970-1972 Chevy LT-1 350

When the 350 small-block Chevy V-8 appeared (along with the also-new Camaro) for the 1967 model year, it was as a mid-performance engine - above the Camaro's standard inline six, but several steps below the big-block 396 that was available in the Camaro SS. By '69 (final year for the first-generation Camaro) it was still playing straight man to hot dogs like the Camaro Z28's race-intended 302, which could be ordered with exotica such as a cross-ram four-barrel intake, with cowl induction on top of that - and tube headers and chambered pipes in the trunk. But as wild as it looked - and as great for high-RPM SCCA roadracing as the 290 horsepower 302 may have been - it sucked on the street. It wasn't very driveable, didn't work with an automatic transmission - and wasn't even especially quick (stock '67-69 Z28s were generally good for low-mid 15 second quarter mile times). All this - and the stolid reputation of the 350 - would change in 1970, when the LT-1 appeared in the Corvette and as the new "second generation" Z28's standard engine. Though it still offered high-performance special equipment like the previous year's 302 - including an aggressive solid-lifter camshaft, high-compression pistons, four-bolt block and an aluminum high-rise intake with a Holley carb on top - the extra cubic inches gave it both superior horsepower (370, according to the press releases) and streetability. It was also a better performer than the old 302 - at least, quarter-mile wise. The new Z28 was noticeably quicker (solidly in the mid-low 14s) and had much more part-throttle punch. Buyers now had their choice of either a 4-speed manual or three-speed turbo-hydramatic, too. Unfortunately, the LT-1 had a brief life due to ever-increasing emissions regulations and was replaced just a few years after it was introduced by the much milder L-82, which tried hard but wasn't half the engine the LT-1 was.

* 1966-1972 Chrysler 440 Magnum/Super Commando

The 426 Street Hemi may be Mopar's rock star engine, but like so many other extreme engines of the muscle car era that were basically race car engine "detuned" for the street - and put into production to legitimize their use in race cars - the Hemi was not at its best idling in traffic. In fact, it wasn't really happy outside of its native environment - the high banks of NASCAR super speedways like Daytona or ripping up the asphalt in quarter-mile bracket racing. Hemi cars still get the big bucks today as collectibles, too. But back in the day, savvy street brawlers knew the virtues of the 440 - in either Magnum (Dodge) or Super Commando (Plymouth) forms. Its rated peak horsepower - 375 at the peak of development - was not too far off the pace of the Hemi's 425 horse rating (though admittedly, the Hemi was probably laughably under-rated). And on-paper numbers or no, the 440 delivered heroic performance in 4,000-lb sheetmetal dreadnoughts that had no business being fast. And yet, fast they were. Blisteringly so, in the case of several examples. The single four-barrel 440 was a tough customer, but for a few years, one could up the ante with a three carb setup known as the Six Pack (or Six Barrel) which pushed the rated output of the mighty engine to within striking distance of the vaunted Street Hemi - on the street, at least. The three carb set-up got cancelled after '71, however - and though the 440 block continued in production through the mid-late '70s, it got crippled up after '72 and continued to lose special parts (and performance) until the end, when it was just a big engine for big boats, all hollowed out and barely belching out 200 honest ponies by the end.

* Ford 289/302

Ford has built a number of standout V-8s over the years, including legends like the 427 and 428, the 390 and 351 Cleveland - to name just a few. But unlike virtually all the muscle engines of the '60s, Ford's sweet small block - the 289/302 - lasted as a production engine for decades after the original muscle car era ended. It was in fact still powering Mustang GTs as recently as the mid-1990s - and was only retired after Ford concluded it could no longer be tweaked to meet constantly tightening emissions and fuel efficiency diktats. (The 4.6 liter overhead cam V-8 took its place in the Mustang for the '95 model year - and though not a bad engine, it lacked the low-speed grunt and muscle feel of the old Five-Oh.) Like Chevy's also-excellent small block V-8, the 289/302 was a very versatile little engine that could be built for economy and smoothness (in two-barrel form, with mild cam - just like Chevy's 307, 305 and even a few 350s) or it could be set up as a full-tilt screamer with a 6,000 RPM-plus redline and more horsepower than it had cubic inches. Early Mustangs with the K-code 289 "Hi-Po" (and its advertised 271 horsepower) are among the most desirable of '60s-era muscle machines - capable of quarter mile times right there with the big block bruisers (14.68 seconds, according to one road test of the time). Ford's small V-8 also held the line during the darkest days of the mid-1970s, keeping at least the idea of V-8 street performance alive (if not the actuality). And when the second muscle car era flickered to life in the early 1980s, it was Ford's Mustang GT - powered by a 5.0 liter "Boss" - that lead the way.

Again.

[Disco Man]

Eric,

Sorry for the hiatus away from the board, but I should be back on more a regular basis now. Great picks on the greatest motors from the golden age of Muscle Cars. I would agree with you on your picks but would add these t your list:

* 1970 Chevrolet 454 LS6 (optional on '70 Chevelle SS)

This engine was the pinnacle of the Chevy's street big block V8 engines. It was factory rated at 450 horsepower, and allowed the Chevelle SS to hit the 1/4 mile in 13 second range (around mid 13's in some magazine tests done back in the day). By the next year the 454 would begin to slowly get its life sucked out with the introduction of the low compression 454 which was introduced to meet the 1972 federal standards to allow for the use of unleaded gas. By 1976 the last year for the 454 in a passenger car, the 454 was weezing at a around 215 horsepower.


* 1971 - 1972 Pontiac 455 H.O.

The '71 and '72 Pontiac 455 H.O. was a monster of a motor, even though it was low compression it could run with the best of the high compression V8s. The 455 H.O. was available on the GTO, Lemans, Firebird Formula, and standard on the Trans Am/71' GTO Judge. For some reason this motor gets over shadowed by the '73 - '74 SD 455, which is in Eric's list above. There has been a debate in Pontiac circles for years which was better the 455 H.O. or the 455 SD. Recently a muscle car magazine (I'll have to dig it up and post the info here later) decided to take on this challenge, they took a stock '71 455 H.O. and stock '74 455 SD and ran the two motors on the gross dyno (like the old days), the figures were shocking. The 455 SD hit around 425 horsepower (which was not a surprise) but the 455 H.O. hit a peak horsepower at around 450 (I'll have to check to see what the exact figure was, since I am doing this all from memory). As a side note the 450 horsepower factory tested figure of the Chevrolet LS6 454 was a gross test. So as you can see the 455 H.O. even with a low compression ratio of 8.4:1 could run with the best of the high compression big block motors. The '71 455 H.O. motor used a Rochester quadrajet 4bbl that was missing its booster venturi rings giving it a slight advantage over the '72 455 H.O. With the booster venturi rings removed it gave the '71 allowed the carb to flow at few more cfms, 800 cfm verses the 750 cfm with the rings (a few years later Rochester would increase the bore on the quadrajet to allow for 800 cfm in some application, instead of removing the rings which did affect low speed drivability).


* Chevrolet 427

This big block V8 motor though originally designed for racing was a legend, from the iron blocks to the aluminum blocks these motors produced plenty of horsepower which on some of the best applications was very underrated.


* Ford FE V8

When the Ford FE was released as the 332 CID V8 for the 1958 model year, Ford would never have guessed the FE engine block would turn into its most reverred and high performance V8s, Ford would ever produce. A few years later the FE would increase to 390, 406, 427, and then 428 CID. It was the FE 427 that powered the Shelby 427 Cobra, a car still reverred 40 years later as the King of the Muscle cars (the Shelby 427 Cobra's 0-100-0 mph time is still hard for even the best of today's fastest exotic cars to beat). Even the 427 Corvettes could not touch the performance of the Shelby 427 Cobra. The Shelby 427 Cobra went 0-60 mph in 4.5 seconds and did the 1/4 mile in 12.4 seconds).

The high performance FE 428 which started out its life as a 428 police package eventually evolved into the 428 Cobra Jet and 428 Super Cobra Jet, were easy to tune and beat a lot of competitors on the street. The Cobra Jet 428 powered Mustangs and Shelby GT500 Mustangs built up quite a street reputation for being hard to beat (the 428 Cobra Jet was also available on the Torino GT, Cougar, etc.). The 428 Cobra Jet could break into the 13's, most tests from back in the day show the fastest of the 428 Cobra Jet cars could hit the high 13 second range for the 1/4 mile.


Also in closing we are in a new muscle car era today, IE: another horsepower war. Who would have thought that another Shelby GT500 Mustang would make the scenes with 500 horsepower that could beat with ease the old Shelby GT500 Mustangs. Another example of this is a test from the December 2005 issue of Muscle Car Review where a 2006 Charger R/T (345 CID Hemi - 340 net horsepower) went head to head with a 1970 Charger R/T (440 CID V8 - 375 gross horsepower). The new 4-door 2006 Charger R/T won in every performance area tested. Here's the breakdown:

2006 Charger R/T - Slalom Speed: 62.2 mph, 60-0 mph braking: 110 ft., 1/4 mile: 14.23 sec. @ 98.78 mph

1970 Charger R/T - Slalom Speed: 58.3 mph, 60-0 mph braking: 144 ft., 1/4 mile: 14.45 sec. @ 97.36 mph

[chiph]

I'd take a 25% shorter stopping distance!

Chip H.

[Eric]

Great stuff, Pete - and no worries about the hiatus!

[Disco Man]

Eric,

Thanks. It's good to be back.


Chip H.,

You're not kidding 25% is a big difference.