(first posted 10/16/2013) She’s real fine, my 409... Well, I guess I rather blew it with my ’64 Chevy CC, seeing as I used only the lyrics of a song for the text (it was very late that night). Because if ever a car was immortalized by a song, this is it. So now I’ll have to actually write something original about the ’63 Impala SS 409. Like taking a good look at that legendary motor under the hood. Or whether the ’63 Impala is better looking than the ’61. Or how about the fact that it seems to inspire women to take their clothes off in its proximity more than any other car?
Well, not in 1963. But do a Google Image search for 1963 Impala, and be prepared. Giddyup, giddyup 409. Well, I’m not going to post any of those here, because I know how distracting that sort of thing can be when we have important historical work to do. Engines are the topic of the day, the 409 in particular. Almost as good as near-naked women.
There’s obviously something about the ’63 Impala coupe that seems to inspire women; or is it the men that pose them with it? Well, it’s a beaut! There’s no denying it, and undoubtedly many consider it the best of the bunch (1961-1964), if not the best looking Chevy ever. It’s certainly going down in history that way…try finding a genuine Curbside Classic ’63 Impala SS, with a 409, no less. I’d long given up hope on that, but then, there it was.
At first glance, I almost kept walking…I just don’t do the typical car-show-cruise-in-mobile-resto-mod kind of ’63 Chevy. I want to remember how they looked and felt in my childhood; isn’t that what CC is largely about? And I want to find them sitting parked on the street. But on closer examination, this one just made the grade, despite the non-stock wheels. At least they weren’t donks, tiny low rider wire wheels, or resto-mod giants. I can live with these.
I was also just a wee bit suspicious when I saw the 409 badge on its front fender. But a closer look put me more at ease. Somebody wouldn’t slap a bent 409 badge on a 327 Impala SS, would they? Do you know what magic that little set of three numerals meant to me in 1963? Seeing a 409 back then in Iowa City was a really big-bore deal, and I always kept a lookout for that possibility, thanks to youthful sharp eyes that could spot those little numerals a half mile away. The first one I saw was a station wagon, wouldn’t you know. And with the Powerglide, no less.
That’s because the overwhelming majority of 409s weren’t all that hot. I’m speaking of the 340 hp version, which had a pretty mild hydraulic cam, modest valves and ports, 10.0:1 compression, and a family-sized four barrel carburetor. It had plenty of grunt where it counted, to haul a wagon-load of kids and stuff up the Rockies on vacation, Powerglide and all. (this engine shot is from Tom’s ’64 409 CC).
The 409 was the next stage of evolution of the Chevy “W” engine, which debuted in 1958 with 348 cubic inches. We did its full story here. It’s a rather unusual engine, in that it doesn’t share anything in common with the famous Chevy small block V8, most of all in its cylinder head design. The top of the block is angled, and the whole combustion chamber is in the bore.
Which means that the cylinder head is quite perfectly flat. This one is from a hi-po 409, showing off its larger valves. And as can be seen from the cross-section above, the valves are staggered, reducing the length of the corresponding port. Those staggered valves also result in the distinctive scalloped valve covers on these engines.
So here’s the real deal, the top of the line 425 hp version, with twin four barrels, big valve heads, 11.0:1 compression, and a mean and lumpy mechanical lifter cam. There was also a 400 hp version, with just one carb. Some say the 348 and 409 have a distinctive exhaust sound, because of those heads. I can’t swear by it, but I did hear a guy’s tri-power 348 a while back as he was showing it off, and there seems to be something to that. Or maybe it’s brain washing. Either way, one of these motors at full chat is a sound to behold.
If a 409/425 wasn’t fast enough, you just had to sidle up to your friendly Chevy dealer and have him order you up a Z-11. This was a drag-race special, with the engine enlarged to 427 cubic inches, and stuffed full of goodies. That resulted in a laughable 5 hp rated increase, to 430 hp. But hp ratings back then were mostly useless anyway.
The Z-11 package cost an extra $1240, which was about a 50% increase over a base Impala coupe. But it was a steal, considering it included a race-ready engine, T-10 four speed, a front clip pretty much all of aluminum, and just about any other goodie in Chevy’s bag of tricks. Shipping weight: 3245 lbs. Seriously. Only 57 were made, and seven are known to exist. Don’t ask what they’re worth.
The Z-11 was for the drag racers only. But folks like Junior Johnson got something even more special from the Chevy Skunk Works, the “Mystery Motor” Mark II 427. It wasn’t available through even your most accommodating Chevy dealer. In fact, it was the last legit factory NASCAR engine out of Chevrolet, as a result of GM’s self-imposed racing ban.
This engine is a hybrid of sorts, as it was based on the 4.31″ bore/3.65″ stroke 427 W Z-11 block, but had the “porcupine” heads that would appear on the Mark IV engine a year or so later. Only a handful of these engines were built, and Junior was the only one who really got it running right, racking up seven wins in the 1963 NASCAR season. Maybe the Beach Boys should have been singing about My Mystery Motor 427. Junior was probably singing When I take her to the track she really shines.
I don’t really know what’s under the hood of this ’63 Impala SS. But since it has an aftermarket shifter for what is clearly a three-speed automatic, it does raise a few questions. The scenario I’d most like to imagine is that this was a 340 hp 409 with the Powerglide, which was replaced with a THM 400 or such. The original console is also MIA, presumably because of the aftermarket shift quadrant. Presumably.
The original-style optional tach has a 5000 rpm redline, which sounds about right for a 340 hp 409. As is evident from the steering wheel, this car is clean, but the upholstery and exterior do show signs of wear.
But the little aftermarket tach down there by the shifter has a decidedly higher red line. We’ll probably never know, unless the owner sees this on the internet and checks in. That happens often enough. I’m betting on a slightly warmed-up 409 that started life as the 340 hp version.
Enough of engines, and let’s get back to beauty. As a kid, I had endless debates about the ’61-’64 Chevys. The ’64 inevitably lost, because it was the dullest of the bunch, and that body was getting mighty long in tooth by then; try a little tenderness indeed. The ’62 had its charms, but the ’61 and ’63 had to duke it out in my mental arena endlessly. There never was a final resolution; they both have their charms.
But fifty years later, it’s time to finally settle this battle, and so I’ll let the women decide. A Google image search for the ’61 Impala shows there’s still a healthy number eager to strip with it, but the ’63 wins pants-down. Time to put that argument to bed once and for all. If only I’d had these high-tech aids back in 1963 to help me with that decision, I wouldn’t have been grappling with this problem for half a century.