I am wanting to make my 302 into a 347 and put a supercharger on it. Does anyone have someone they recomend to do this job. I want to go with a dyer 870 blower with a black wrinkle finish
What year 302 block? If it's a roller cam engine they tend to split down the middle at around 500 hp. 347's put the piston pin in the oil control ring land. So you will get questionable life from it in a supercharged application and you will likely have high oil consumption. If you must use a 302 block as a basis I would recommend a 331. IF it can be based on a 351W, they are a much better choice. Stronger. Not much bigger.
Unless you use a high nickel aftermarket block it will split in half under that kind of power, and low compression pistons for that motor are very expensive, 351w is the way to go with a blower.
I've had 3 diffrent people tell me they pulled 347s out for poor oil control, & those wern't blower motors either.
---------------------------------------------- In stock 2V form, compared to a stock 351W - the Cleveland has better flowing heads , but weighs more and has a weaker bottom end oiling system than a 351W "Good" 351 Cleveland parts - ie - 4-bolt "Boss 351" blocks and good heads - ie - 'Boss 4V' or 'Austalian 2V' heads - are scarce and pricy. For your proposed high-hp blown application, I'd choose a 351C over a "302-347 stroker", but I'd still choose a 351W with some good aftermarket aluminum heads over either a "302-347 stroker" or a 351C. Far cheaper to build, easier to get parts for, stronger block and bottom end and with the plethora of good flowing aftermarket Windsor style heads that are available now, more powerful too. Mart3406 ======================================
Every 347 that's had oil control issues has had 5.400" length connecting rods. There are 347's that use slightly shorter rods that reportedly don't have the oil control issues.
also with a 347 use the 351w fireing order not the 302, also i dont know if the bottom end ( 2 bolt mains ) will support much boost. 12-1 pistons and no blower pushes the envelope
Lots of Mustang racers run supercharged 347 strokers, but keep in mind that with the bigger inches and boost, it doesn't take too much to get pretty close to the engineering limits of the block as far as horsepower is concerned. Strong blocks are available, but the vendors are pretty proud of their stuff; the bigger Windsor blocks are stronger, but taller, wider and heavier. Pick your poison.
Have a look here........ http://www.sbftech.com/ Just about any and every question you could ask about the sbf has been covered.
These guys to a lot of sbf http://www.performancesolutionsinc.net/ I use them for all my customer motors 6-10 a year, plus my race motor.
This is an extreme example. There are many, many supercharged 302's with 14-15 psi of boost living happily. Much of it is in the tune of the engine.
Yup. I build quite a few 347s. Needs to be the older block with the solid main web threads. And I can't say I lean on the blower to hard >>>>.
I would suggest that you get one of the new Boss 302 4 bolt main blocks that are being reproduced.... they have screw in freeze plugs, thicker cylinder walls and stronger webbing in the block.....
only problem with the new boss is that the cylinders are actually shorter at the bottom and the 347 will only work with mahle pistons (they apparently have a shorter skirt or something) my buddy just ran into the issue. If you have to have a sc 347 then I would suggest an older block, adapt some of the new block braces to it meant for the fox mustang guys, and use forged internals. Personally I would build a 351w based stroker, but then again I run standard 302s in almost everything I own
302 ford engines are probably one of the best engine out their, until they destroy themselves. You see, with the current parts out their, it's child's play to build one that self destructs. I know, mine is on borrowed time, though it's lasted me for over 10 years on the same block running 10s in the 1/4 with some juice. I pulled it apart to fix some stuff, and I am seeing signs of cap walk, even with a stud girdle. If you are going to be building anything do yourself a favor and get an aftermarket block. It looks like I'll be going with a dart block after this summer, and if my current block lasts I will use it for the base of a fancy coffee table for my office, I figure I could powdercoat it and with a nice mahogany top it would look cool and I could store wine bottles in each cylinder hole. P.S. Ford would have had a win with the new Boss block, but they messed up and made the cylinder skirts too short. GRRR!!! Or one other option you could try to find a mexican block, or a old boss 302 block... stay away from late model blocks.
stock 5.0 roller blocks are good until 450 hp. most ford engine builders recommend an aftermarket block for high hp engines, especialy if running alot of boost. if your on a budget, go with a 331 and keep the boost limited to a couple pounds. i have a n/a 331 in my falcon and its estimated hp is 400 and it runs really good. doesn't burn oil and runs just fine on 92 octane.
High hp & boost don't = a 302 ! 347's are nice as long as they are built the right way with a GOOD block ! there are some mods to do for a good running 347 . But with that much money tied up into a 347 why not use a 351w . A Cleveland is nice but with the weight I would use a 460 and be done with it ! It's very easy to get 500+ hp from a 460 and with some good heads and a roller can 700 is not hard either ! What I am trying to tell you , if you want big hp and torque get a BIG BLOCK ! I have both , a 302 and a 460 . A 302 is a GREAT engine and still get 400 hp , but if you want big hp then go with a 460 . You can get a running 460 for $600 and either rebuild and port the stock heads or spend $200 and get some good ones . There is NOTHING like the sound , torque and HP of a BIG BLOCK ! You won't be sorry you built one either , plus they don't break that easily like a small block either ! If you want to know more about a BBF build just ask ! Retro Jim
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