Ive noticed most every late model V6 and V8 are deep skirted blocks In the 70's Buick was the only manufacturer casting their V6 and 350 this way along with Mopar with their 383/426/440's Now it seems EVERY V6 and V8 block is cast this way. The only reason I can come up with is the deep skirt provides greater strength along with light weight. Was Buick really that far ahead in design and engineering back then? Tall skinny intake ports to promote mixture velocity Aluminum timing cover/water pump Buick was poo pood for using steel gears in an aluminum oil pump housing. Today, thats how everyone is doing it, would you run steel bearings on your crank??? Shaft mounted "net lash" rockers Too bad Buick isnt in the game anymore.
There's only so many ways to make an engine. Everything new is basically recycled with a bit of polish on it. Electric vehicles were first produced over 200 years ago. Diesel engines are over 100 years old. Full auto firearms where invented more than 100 years ago. Even planes are more than a century old. I dare say Henry Ford, Rudolf Diesel, Wilbur & Orville Wright, Gen John Thompson and Hiram Maxim would have no trouble understanding the most modern iterations of their groundbreaking inventions. The biggest changes have been better metallurgy and precision machining.
If deep skirt blocks where the way to go for ultimate strength then pro stock motors would be built with them! In all too many previous deep skirt iron production blocks most of the material that should be in the main webbing and cylinder walls is put in the skirt. Once your at a G force level that's enough to start cracking out the main webs it does not matter that the block for example like a Ford FE motor with cross bolted main caps has a deep skirt.
Buick started with the deep skirt design beginning in the 30's with the 1st. straight eight. I believe even the early 6 cyl. were deep skirted. As far as running steel against steel the only way to get a higher lift out of the cam on the flathead V-8 was to run without cam bearings & they lasted. Tom T.
Well consider this. The SBB iron block is within about 2 lbs of the weight of the Ford 302 block which is not skirted. The 302 is good for around 500 horses before the block has to be reinforced in some way to prevent it splitting down the middle. Unmodified SBB blocks have seen around 700 hp. Coincidence? I rather think not. Jim
What is interesting is the big block was really the last engine Buick designed and they opted not to make it a deep skirt block. We all know the modern 350 was just a slight redesign of the 215-300-340 series. The deep skirt was leftover nailhead stuff. Must be they saw no value in it, as they knew the 455s would make way more power than the 350s would. That extra weight of the deep skirt doesn't do much without cross bolting the mains to it. Yes most everything these days is deep skirt, but the main caps are either part of a full girdle assembly or cross bolted. That design I am fairly certain came from Japan. The Northstar is the first (I believe) domestic engine with girdled mains. The Northstar I think is the true predecessor to the LS. GM certainly learned a few lessons with it... I still say the 350 block is largely untested. Besides a handful of a few serious builds, they just haven't been tested like the BBB. Show me 100 350s that are in 9-10 second cars with no girdle...
As told to myself by Dennis Manner. They were looking for a way to try & lighten up the cars because by 1970 they were getting larger/heavier by the minute. One way was to lighten the block. AND, this started in 1967. Tom T.
True! I think it will probably stay that way because people view the 350 as “yawn, it’s a 350” and from its smaller than 4” bore, and from the few sets of aluminum heads sold with no decent, accurate, current reports of “WOW what a difference” I’m happy I cancelled my order after near two years and nothing done on them after a big deposit, I’m pretty confident it would have been a big investment with a small return.
The way the 350 block is designed looks like diesel block technology, they use 2 bolt main caps, and the caps do not touch the outter block wall, they have similar cast in tapered bulkheads, so there must be something to that type of design that lends strength to the block.
The diesel blocks have a cast iron trans hanging off the back of them that weighs almost the same. Its apples oranges..
I should mention big rigs typically don't have a rear crossmember for the trans. The entire weight of the trans is supported by the block.
You guys go off on all these tangents that mean nothing. OK, how about the V6? That's the SBB with two cylinders lopped off, do you think that MAYBE the GN engine was tested enough to suit you? In terms of reliability and power/weight it seems they are up there quite a ways and the V8 can beat them when it's set up the same way. Show me an inherent block failure in a SBB. Ever seen one? Meanwhile guys like GS Johnny are winding it into the nines on the regular. Gimme a break. Jim
My opinion, no facts to back it. The og Buick small block was cast in aluminum, 215, that is why the block design was skirted and designed to be more rigid. Remember aluminum is not as strong as cast iron. Buick started casting them in iron in 64 with the 300 and the block was a carry over, so the extra inherent strength was just a left over and a bonus. I always think about how cool it would have been if Buick could have refined the aluminum casting process and stuck with it, all aluminum 300's, 340's and 350's. Who knows, by 67 even the big blocks could have been aluminum, that would be cool. Thanks Brent
Yet the weight difference between the SBB block and the late (and improved) Rover block is right at 50 lbs and the Rover block is not even remotely as strong, durable, or trouble free. I'll take the iron block any day. And did you know that if you buy a TA aluminum block for the BBB you save little or no weight over the iron block? Just one of those little known factoids. It seems that aluminum may not be much of an advantage at all over a good nickle grade of cast iron like Buick used. Jim
Granted, but then the TA aluminum block's design intent is much more broad than the OEM BBB. I don't think anyone is purchasing the Tomahawk for weight savings, unless they're graduating from the old aftermarket cast iron Bulldog block. Devon
You are "Right On", Plus More.......... I'm a retired machinist over 40+ years. Metallurgy, precision machining, 3-D Computer Aided Design (like CAD/SolidWorks), and CAM Computer Aided Manufacturing (like FeatureCAM). Have dramatically changed the ability to design and manufacture precision products and equipment. Even to the point that it's now possible to machine geometry that was never possible with non-computerized machinery. Even machining cutting tools have been upgraded from carbon steel cutting tools to carbide, ceramic and diamond. New Metallurgy creations allow the building of much stronger and lighter materials and a new combination of alloys never seen before. We have better heat-treating methods, allows us to create much stronger materials. Even chemical processes that allow us to harden parts like crankshaft journals (called nitriding -the process of heating steel in the presence of ammonia or other nitrogenous material so as to increase hardness and corrosion resistance). In the plastics world, there has been a huge improvement in this field. When you look at present day technologies, everything has seen light years of improvements. My grandfather was a machinist too and owned his own business. I'm sure he would be amazed at today's technologies, probably blow his mind. Lol Vet
