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Discussion Starter · #1 ·
What do you guys think about a blown bronco? Supercharged that is. I've toyed with the idea of turning the 460 I'm building for it into a blown 460. Honestly, for as much (or little) as it is going to be driven I'm not really concerened about the gas mileage. It's going to suck with or without a supercharger. So...what's everyones opinion? :popc1:
 

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DO IT!
 

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Engineer
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Sounds like a cool idea
 

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:stupid, go for it, sounds like a great idea.
 

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TX_BEAST said:
i like the idea i was thinking about doing it on my 351m because http://www.blowerdriveservice.comoffers them. i just think it would be awsome to hae the blower sticking out of the hood.

So are you talking about the 351c or 400m that will fit on the 351m. James
 

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You can't beat a blower for producing power. We've got a 460 with a 671 on top, 10% underdriven and 14 psi of boost.

BUT..plopping a blower kit on your stock 351m is not going to work very well or very long for a number of reasons, not the least of which is the lousy quench characteristics of the stock engine. In simple terms..it cannot stand the increased dynamic compression you will get from the blower.

If you changed to the 400 crank and used forged 32cc zero-deck pistons with Aussie, CHI or Edelbrock closed-chamber heads and a very conservative blower drive (maybe 15% under) you would have a torque monster that might live for a while. The pistons, heads and related machine work are all pretty expensive

We live and breath extreme 400 (we refer to them as 'Super Clevelands') builds here at our shop..but for the cost and results, I would have to say the 460 would be a better foundation for a supercharged engine.
 

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bmc69 said:
You can't beat a blower for producing power. We've got a 460 with a 671 on top, 10% underdriven and 14 psi of boost.

BUT..plopping a blower kit on your stock 351m is not going to work very well or very long for a number of reasons, not the least of which is the lousy quench characteristics of the stock engine. In simple terms..it cannot stand the increased dynamic compression you will get from the blower.

If you changed to the 400 crank and used forged 32cc zero-deck pistons with Aussie, CHI or Edelbrock closed-chamber heads and a very conservative blower drive (maybe 15% under) you would have a torque monster that might live for a while. The pistons, heads and related machine work are all pretty expensive

We live and breath extreme 400 (we refer to them as 'Super Clevelands') builds here at our shop..but for the cost and results, I would have to say the 460 would be a better foundation for a supercharged engine.
One of these days I hope I can understand and contribute such technical knowledge.:rockon
 

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78rangerbronc said:
One of these days I hope I can understand and contribute such technical knowledge.:rockon
LOL..thanks for the compliment but we - like most 'old school' builders - learned an awfull lot of our hipo engine building stuff the 'hard' way. Roughly translated, that means: "Spend gobs of money on the next great idea and figure out what ya did wrong when it scatters". I started building racing engines in the late 70s..with the proliferation of internet sites containing so much knowledge and experience, life is much better for all these days. Fortunately, what we learned the old-fashioned way is still valid too.:thumbup
 

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Discussion Starter · #16 ·
So...just two questions. Would the stock crank be able to handle a 671 and would I need to use a "blower cam" or can I keep my 4x4 cam? I'm already going to use forged flat tops for the pistons. I've never done a blower engine before so it would a whole new experience for me.
 

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bmc69 said:
You can't beat a blower for producing power. We've got a 460 with a 671 on top, 10% underdriven and 14 psi of boost.

BUT..plopping a blower kit on your stock 351m is not going to work very well or very long for a number of reasons, not the least of which is the lousy quench characteristics of the stock engine. In simple terms..it cannot stand the increased dynamic compression you will get from the blower.

If you changed to the 400 crank and used forged 32cc zero-deck pistons with Aussie, CHI or Edelbrock closed-chamber heads and a very conservative blower drive (maybe 15% under) you would have a torque monster that might live for a while. The pistons, heads and related machine work are all pretty expensive

We live and breath extreme 400 (we refer to them as 'Super Clevelands') builds here at our shop..but for the cost and results, I would have to say the 460 would be a better foundation for a supercharged engine.
sorry i didnt specify, i would not try to just slap a blower on there.i under stand that forged pistons are needed, but im not trying to argue but the you could get away with the factory heads just have them ported and the valves unshrouded and all that good stuff that you would get from a good head job. then just push a little more air in the combustion chamber to make up for the lower initial compression ratio.
 

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TX_BEAST said:
sorry i didnt specify, i would not try to just slap a blower on there.i under stand that forged pistons are needed, but im not trying to argue but the you could get away with the factory heads just have them ported and the valves unshrouded and all that good stuff that you would get from a good head job. then just push a little more air in the combustion chamber to make up for the lower initial compression ratio.
The fundamental problem with the open-chamber Cleveland heads is that there is no quench pad..hence no quench. It is well-understood that the Clevo open-chamber configuration has very real limitations on compression before a serious problem with detonation occurs..it is why Ford ended up dropping all the way down to 7.9 in their feeble attemtps to get the engines to live on 87-unleaded gas with the open-chamber heads. A 9.2:1 static compression is about that limit without going totally exotic on your fuel mix. If you ran a blower on top of a stock 8.0:1 motor, you would think that is OK..typical blower-piston CR, right? However, the dynamic CR is much higher with the blower in operation..and detonation becomes a severe problem with that configuration. Water injection and serious doses of 108 booster and it would probably live..

The 460 we built with a 671 huffer on it is quite happy with 92-93 unleaded pump gas...but those heads have quench pads too.

That was
 
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