Then there are the Commercial Engines, Fleet Engines, Industrial Engines, -----------

 

Somewhat true - semantics I guess -unless you are weight critical - or space critical.

The 351C engine weighs 100 pounds (20%) more than the 289/302. The FE weighs 200 pounds (40%) more than a 289/302; and a 428 weighs 275 pounds (45%) more than a 289/302.

If you don't think that an extra 275 pounds is going to cause issues when converting engines in your truck, I'll be happy to post a picture of my passenger side leaf spring and the $650 quote for springs that will support the torque and weight of the BIG BLOCK FE Engine.

Then there is exhaust. Block hugger headers will fit fine on what I'm calling "Small Blocks" in a Bonus Built or Effie with a stock steering box/front end. With the Cleveland, FEs, or 460 group you will have to make other arrangements. Small words and little differences, but just enough to cause significant, and expensive impacts. And I believe that was the question the original poster was looking for.

With the excerpt that was posted - absolutely. And it better not ever happen again!

 

OK.............SO, assuming you have decided a 351 W is what you want, what year block would you start with to build a reliable, normally aspirated (carborator), with around 250 to 300 HP?

Julie...........you go girl!

 

Well, lessee here, the 351W was available in two different deck heights. '69-'70 had a 9.48" deck height and '71-up had a 9.50" deck height. The latter figure is considered to be "standard" and is the measure that all aftermarket piston suppliers typically operate off of, so I'd shy away from a '69-'70 block lest you run into deck clearance issues. Beyond that, it doesn't really matter. The mid-80's and up blocks have thinner castings to conserve weight, but there have been no strength issues in the 351W's that I am aware of like there are with the late thin wall 5.0L blocks. The 5.0L's have a reputation for splitting the block clean in half at about 500 HP - if you want to call that a weakness. For your purposes, find the newest, cleanest virgin block that you can. Fuel injected engines are preferable because they have little to no cylinder wear compared to a carbed motor. '94 and up 351W's are roller ready blocks, so that's a plus if you want to go with a roller cam. With a decent set of heads and a capable induction system, a 351W should be able to produce 250-300 HP without even breaking a sweat. You'll never hurt a block at that power level.

 

Wow.....good advice, Thank you. I've been trying to do my homework and make intelligent decisions... but....the more I read, the more questions I have. You do realize you may get about 10 million more questions from me now don't you?!!
Like: do I need to reconsider the fuel injection verses carb?
and: is the roller cam really needed in a modestly built 351 when I'm only looking for ~300 HP?


PS

 

Boss 302 uses it's own block, 4 bolt mains. The Boss was developed because the 302 tunnel port motors came apart at high rpms. Those were "standard" 302 blocks.

The Boss came first, so it's more like the Cleveland motors used heads patterned after the boss.

As for a search, I posted a link with tons of trivia about all these engines. It is the link(s) that appear at the top of the Small Block forums.

 

The EFI versus carburetion question is a matter of personal taste, mechanical and electrical ability, and intended usage. Carbs and their fuel systems are simple, easy to troubleshoot and maintain, and fairly reliable. They are also somewhat inefficient, difficult and time consuming to dial in, and can contribute to accelerated engine wear from an overrich mixture without meticulous maintenance and a spot on fuel curve. EFI delivers excellent fuel mileage, unparalleled reliability and driveability, requires very little maintenance beyond an occasional fuel and air filter, and can even tell you where it hurts when something breaks. It is also complex, requires a little knowledge and thought to install, and can easily overwhelm an unfamiliar installer.

Obviously, an EFI system on an otherwise stock truck or one with period correct mods would look "odd". Some cars and trucks just need a carburetor to fit the theme. Weekend cruisers or fair weather only trucks probably would be better off with a carb, too. EFI does add some complexity and a bit of expense to a build and a truck that doesn't get driven much will never give it's owner/builder an opportunity to see the payback in fuel savings, reduced engine wear, and driveability.

But if you have already made other upgrades and modern modifications and you intend to drive the snot out of it, then why not? It does add a degree of difficulty to the engine and drivetrain installation, but the amount of information and tech help available in the 'net today on the subject greatly simplifies it. Reusing an EFI wiring harness from another vehicle is the least expensive way to go, but can also be the most difficult and most time consuming. For an EFI newbie, I'd recommend an EFI harness from Painless Wiring or the like. If you can read and follow instructions, then you can wire up EFI with one of their kits. There really isn't any voodoo or magic going on with this stuff. The technology is 40 years old now and is certainly not rocket science. I add EFI to nearly everything I own. I like it, but then I also hate carburetors. It ain't for everybody.

As for the roller cam, I always run one when possible. The lobe profiles that are possible with this arrangement allow big power with Lincoln Town Car street manners. These traits were always exclusive or a compromise at best with flat tappet grinds. This is really just a minor issue, though. The big problem with flat tappets is the oil that's available nowadays. Up until about 15 years ago, any oil that you bought had copious amounts of this stuff call ZDDP. It's an extreme pressure additive that helps parts operating in sliding friction conditions live long lives without wearing out. It's also very bad for catalytic converters, so our friends in the federal government forced the oil companies to phase it out. Google "wiped cam lobe" and you'll be reading all night about the results. This is why all modern engines have roller tappets or cam followers today. Plain old oil just won't cut it for long engine and valvetrain life with a flat tappet cam. There are a couple mail order additives that will restore ZDDP to proper levels for use in flat tappet engines, but it adds about $10 to an oil change and you have to mess with ordering it. Nothing is available locally that will substitute.

You can easily build the 300 HP you're looking for with a flat tappet cam and a fairly mild one at that. Just do a little research on ZDDP and be prepared to deal with the extra maintenance hassle. Check out ZDDPlus™ - ZDDP Additive for Classic Cars - Agricultural Equipment & More for lots of interesting info. On the other hand, if you find a '94 and up roller block, you can pick up a used stock 5.0L HO cam for it dirt cheap. Couple that with a set of salvage yard GT40 or GT40P heads and you'll easily be at your 300 HP target with nothing but junkyard parts.

 

BLUEOVALRAGE! that was a very informative post! Thanks for taking the time to outline this for me! Now I know what I'm looking for. I believe at this point I'll stick to my original carborated engine idea and look for a post 94 roller.

PS