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do 351s wear out as fast as 347s?

  • Thread starter Thread starter leakyfaucet
  • Start date Start date Jan 20, 2004
L

leakyfaucet

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Dec 19, 2003
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Jan 20, 2004
#1
  • Jan 20, 2004
  • #1
Since 347s wear out rather quickly due to an increased stroke and a bad rod ratio, wouldn't a 351 wear out just as fast if not more, due to its increased stroke and rod ratio? If so, why do people fear getting a 347 when 351s came with an even longer stroke from the factory?
 

cardudeusa

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Oct 22, 2002
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Jan 20, 2004
#2
  • Jan 20, 2004
  • #2
A 351 is much stronger than a 347. I dont know the exact specs but to answer your question, no it will not wear as quick as a 347.
 

GTPhreak

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#3
  • Jan 20, 2004
  • #3
351's have a taller deck height so they have more area and arent stuffing the the equivalent of 347cubic inches in a block designed to hold 289/302 cubic inches.
 
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caine0

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Jul 13, 2003
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Jan 20, 2004
#4
  • Jan 20, 2004
  • #4
leakyfaucet said:
Since 347s wear out rather quickly due to an increased stroke and a bad rod ratio, wouldn't a 351 wear out just as fast if not more, due to its increased stroke and rod ratio? If so, why do people fear getting a 347 when 351s came with an even longer stroke from the factory?
Click to expand...

A 347 would be a 302 with a stroker kit on it. So a 347 is not built to be a 347 from the factory, it is built to be a 302. Once you strip that material away from the engine, it becomes less able to take abuse for long periods of time since there is less support. A 351 is built to be a 351, that's why you can stroke it out to largers sizes as well. A 351 can handle more horsepower than a 302, which means it can handle more horsepower/abuse than a 347. Hope this is what you're looking for

There are people on here a billion times smarter than I am, so if you need more info just post again and somebody else will answer
 
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leakyfaucet

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Dec 19, 2003
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Jan 20, 2004
#5
  • Jan 20, 2004
  • #5
caine0 said:
A 347 would be a 302 with a stroker kit on it.QUOTE]
I know, and I know 351s are stronger blocks. But what I thought made them wear from the long stroke was the increased pressure on the sidewalls.

Wouldn't the 351 have a lot more pressure on the sidewalls than a 302, wearing out the piston rings and scraping the crap out of the sidewalls?
Click to expand...
 

cardudeusa

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#6
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The side walls are not going to be as thin as a bored 302.
 
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proxses

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Dec 12, 2000
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Dayton, Oh
Jan 20, 2004
#7
  • Jan 20, 2004
  • #7
Longer rods in the 351. So less rod angle and less wear compared to a 347.
The deck on a 351 is either 9.2 or 9.5". I don't remember which.
The 347 has an 8.2" deck height. Less room for long rods, so you get a less optimal rod angle.
 

IndyBlk5.0

New Member
Nov 24, 2003
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New Whiteland, IN
Jan 20, 2004
#8
  • Jan 20, 2004
  • #8
well on average, how long will a 347 last? just give me a ballpark view, i am thinking of building one but i want it to last
 
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quicksilver03

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May 27, 2003
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Miami/Orlando
Jan 20, 2004
#9
  • Jan 20, 2004
  • #9
so, how much power can a 351 handle safely with forced induction? u can bore the block, stroke it as much as u want, just what to know what the block can handle. how much of a difference between a block u recover off an old car, and something u buy off ford racing that has Siamese cylinders. more curious in what i can recover off an old car, since it's a lot cheaper, but will get a real good block if necessary.
 
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