[SRR]

https://www.macsmotorcitygarage.com/...i9NecwPknzvp74

"The 409 story actually starts here, with the 348 cubic-inch W-Series V8 (above) introduced for 1958. Chevrolet product planners recognized that domestic passenger cars were rapidly growing in size and weight, topping two tons, and feared that the small but mighty 283 CID V8 would soon be insufficient. Experimental X and Y-Series engines, essentially scaled-up versions of the small-block V8, were tried before the Chevrolet engineering team, led by John Rausch, Howard H. Kehrl, and Donald H. McPherson, determined that an all-new engine was the preferred course.

The name for the W-Series V8 is easy to remember due to the distinctive valve cover shape, which resembles the letter W, sort of. Goals for the new V8 included low manufacturing cost and a compact footprint so it could fit in the same vehicle applications as the small-block. Mission accomplished, as the W-Series arrived only 2.70 inches wider and 1.78 inches longer than the existing V8. The initial 348 cubic-inch displacement was obtained with a bore of 4.125 in. and a stroke of 3.25 in. Bore spacing was 4.84 inches from center to center, identical to the Chevy Mark IV V8, better known as the big-block V8, that Chevrolet would introduce some years later (1965).

Of course, the trademark feature of the W-Series V8 was its distinctive combustion chamber design. In place of a conventional bowl-type chamber in the cylinder head. the block deck was milled at 74-degree angle (16 degrees from perpendicular) to form an oval, wedge-shaped chamber in the top of the cylinder itself. While unusual, this design was not quite unique. Ford Motor Co. also used this configuration on its MEL V8 engine family of 1958-1967, and it was found on some industrial engines in America and Europe.

According to SAE paper no. 590014 presented by General Motors in 1958, the design team was attracted to this design because it supported a variety of displacements and compression ratios with a minimum of tooling changes. The flat, chamberless cylinder head deck also provided generous squish and quench area, as shown in the illustration above. However, the setup did require a big, heavy piston with a tall compression crown, as we can also see. Compression ratio for the original 348 CID version of 1958 was set at 9.5:1, while the 409 CID V8 sported a CR of 11.25:1 when it launched in 1961."

[Brian Baker]

True story:

When the 409 was first introduced, very early in its production, Chevrolet dropped one off at Smokey Yunick's garage for his evaluation for NASCAR use. After a few days he called Chevrolet back and said "come and get this POS out of my garage".

True story.

This was when he was winning races with Pontiacs.

[69droptopraiii]

She’s real fine
My 409

[salem1912]

All that and they look cool too.

[Murf]

No mention of the 348 being designed for big trucks originally. Hence the “Ridge Route Motor” moniker.

I saw a cool GM film about it years ago. A quick google search found nothing though.

My

[hurryinhoosier62]

Dad had a ‘58 Bel Air with the 348. He like it, but talked about valve float at 5500 rpm.

[dhcarguy]

My first cool car I bought was a 1965 Impala SS convertible, 409 , 4speed. (early production). I was 17 at the time in 1970. I paid $800 for it . I went to Al Wilson Pontiac to look at GTO's and the used ones they had were just to much for me. I had to borrow $60. off my dad to get it out the door.
Those were the days

[Diego]

Originally Posted by Murf

No mention of the 348 being designed for big trucks originally.

That's because it's not true.

[Murf]

Originally Posted by Diego

That's because it's not true.

Well, That would explain why I can’t find any reference of it on the web.

I guess I imagined the old video but I swear I saw it. Old age I guess.

Thanks for the correction.
Murf


Sent from my iPhone using Tapatalk Pro

[428goat]

The 1st car I bought my Xwife was 1958 Biscayne 2 door with 348 with tripower. It was used and this was around 1964. It would pick up a go as I remember. I got it from one of my friends. . No power steering and she had a tuff time parking it. Sold it and got her a 1962 Bonneville convertible. Nice car.

[mgarblik]

I have the SAE presentation papers for almost all the engines we love from the 1950's and 60's. They are really fun to read every now and then. Each has a unique story to tell from the engineers point of view, what was really important to them, the division, and GM in this case. In the "w" engine one, it was clear that cost cutting was the major player in the design. Not that that is bad per-sea. But they call out specifically the "advantage" of not having a cast timing cover, not needing the extra weight of a deep skirted block, the flexibility and cost savings of not having a combustion chamber in the cylinder head. It's really fascinating. They were also ahead of the curve a little talking about the advantage of the moving combustion chamber, (piston), and it's positive effects on mixture motion, a more homogeneous air/fuel mixture, and more torque as the primary benefit. It's cool stuff to read.

[mgarblik]

Originally Posted by Brian Baker

True story:

When the 409 was first introduced, very early in its production, Chevrolet dropped one off at Smokey Yunick's garage for his evaluation for NASCAR use. After a few days he called Chevrolet back and said "come and get this POS out of my garage".
True story.

This was when he was winning races with Pontiacs.

It is very easy to see why Smokey Yunick was "underwhelmed" with the "W" engine for NASCAR racing. Fairly weak bottom end, very heavy pistons, cylinder heads that didn't lend themselves to conventional porting, flimsy, angular valvetrain. Lots of oil leak paths. I can see him chewing the end off his pipe and cussing up a storm over that engine. Especially after his success with the simple, strong, reliable Pontiac's he had already worked out. But his "mystery motor" was just around the corner. Probably the single biggest boost for that engine family was having the Beach Boys write a hit song about them. Much like our Pontiac hobby, there is a small dedicated group that have worked out that engine package over the past 50 years and they can be made to run pretty hard. I think they are interesting and a a clear evolutionary path to the Big Block. 409 \409 HP vs 421 SD, no contest IMO. But this is a Pontiac site. I am sure the Chevy message boards would have a much different opinion. However, I don't think many 409 based engines are making over 1100 HP NA, and over 3000 HP with power adders like Pontiac based engines are..

[Diego]

Originally Posted by Murf

I guess I imagined the old video but I swear I saw it. Old age I guess.

Well, not quite. It's an old wive's tale. Every time someone mentioned the 348, someone else says "truck engine!"

I've attached some info that fills ya in.

[mgarblik]

Those of us who have had our beloved Pontiac cars and engines, denigrated by every other brand, especially within GM had our own little nicknames for the Chevy based engine families. Around the Mopar circles, Ford and BOP faithful, Chevy engines were always referred to as: Small blocks= ice cream truck engines
Big Blocks= school bus engines W blocks= dump truck engines. Just our juvenile little digs for the last 50 years. Now I know where the "dump truck" engine term came from. Didn't realize 2 1/2 ton trucks were a design criteria for the W engine. Interesting stuff.

[77 TRASHCAN]

Where is Skip (Mr. 409), in this conversation....? Probably basking in the awesome warm spring air in his new shop, ignoring the internet!!!

[John Milner]

409's came in fire trucks too. This is my 409 that I'm building. It came out of a 1964 model Spartan fire truck. It had roughly 15,000 miles on it. I'm sure that it had a lot of hours on it though. When I tore it down, the short block was in excellent condition. All it needed was a hone ran through the bores. Truck 409 blocks differ from car blocks in that they have an extra machined area in the combustion chamber of the block. That, along with some low compression pistons put a truck engine at around 8:1 compression. So, to raise the compression some, I found some really nice 409/409 horse pistons and pressed them on the factory rods after I installed some ARP bolts in them. The truck heads had a small combustion chamber in them that would lower compression even more. I ended up working over a set of '64 car heads that did not have the combustion chamber. I would figure that my compression will be around 10:1 now. I am not quite finished with it but will finish that up soon. It's not a Pontiac but I think it should run pretty good.

[77 TRASHCAN]

Milner, what are you putting that in??? Did you get all the brackets and pulleys, also???

What type of induction will it have???

I always thought it would be cool to have one of these engines in something...but everything about these engines can be tough to obtain...I guess a 409 in a Hot Rod would suffice. Not a lot of miles and one would not install questionable parts in/on one...

Thankfully in this day and time parts via the internet can help these antiques out a lot.

[GT182]

Was the 409 considered a "small block" or a "big block". I've seen a couple never asked.

Imagine Pontiac building a 409 and putting it in a GTO.... say '64 up it '67. Now that would have really turned heads.

[lust4speed]

In 1963 my '63 Impala SS with a 327 never lost a race to a 348 on the street. They had the reputation of never running anywhere near right, and even back then we referred to them as lumbering truck engines.

[chevymad]

I've read that you can machine a 454 crank for use in a truck 409 as a stroker. Had the thought to do that years ago when we had a 63 dumptruck with a 409. Thought it would make an interesting engine for our 63 impala.