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331 vs. 347

  • Thread starter Thread starter wishihadastang125
  • Start date Start date Jan 14, 2004
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wishihadastang125

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Apr 11, 2002
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Jan 14, 2004
#1
  • Jan 14, 2004
  • #1
dss sells them for the same amount why would you want the 331 & not the 347?
 

wishihadastang125

Founding Member
Apr 11, 2002
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Houston
Jan 14, 2004
#2
  • Jan 14, 2004
  • #2
ttt
 
L

leakyfaucet

Member
Dec 19, 2003
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North Carolina
Jan 14, 2004
#3
  • Jan 14, 2004
  • #3
Most people believe that the 347 wears out faster, due to a poorer rod ratio. I also believe this.
 

wishihadastang125

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#4
  • Jan 14, 2004
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awsome thank you. also is dss a good company?
 

Gearbanger 101

Straight Outta Locash
20+ Year Stangneter
Aug 10, 2002
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Jan 14, 2004
#5
  • Jan 14, 2004
  • #5
Durability - (albeit slight, the rod ratio on a 347 causes more side wall load on the cylinders than the 331)

Performance - Although the 347 has more displacement and the ability to make more overall power, the 331 is more "rev happy" and will spin up a lot easier. Not to mention that it’s better rod ratio actually keeps the piston at the top of the stroke a little longer for a more efficient burn than other designs.

Cost - the 331 is a slightly less expensive kit and doesn't require notching the cylinders in order to clearance it's rotating assembly.
 

billetunderwear

I've posted way more than my fair share of pointle
20+ Year Stangneter
May 14, 2002
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Jan 14, 2004
#6
  • Jan 14, 2004
  • #6
Gearbanger 101 said:
Cost - the 331 is a slightly less expensive kit and doesn't require notching the cylinders in order to clearance it's rotating assembly.
Click to expand...
... unless you use h beam rods.
 

Smokedawg

Founding Member
Jul 6, 2001
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Jan 14, 2004
#7
  • Jan 14, 2004
  • #7
My has a 347 with over 70K on it..Mine only has 1500 total miles but I love it...
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
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Jan 15, 2004
#8
  • Jan 15, 2004
  • #8
Most I beam configurations require notching of the cylinders also... I've put 2 different assemblies together and they both needed notching on most cylinders.
 
A

austinGT

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Apr 21, 2002
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Jan 15, 2004
#9
  • Jan 15, 2004
  • #9
How well does the 351w hold up?
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
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Jan 15, 2004
#10
  • Jan 15, 2004
  • #10
austinGT said:
How well does the 351w hold up?
Click to expand...

Fine, they will also take more HP then a 302 even with a stock block and internals.
 

Black331Stang

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Jan 15, 2004
#11
  • Jan 15, 2004
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wishihadastang, i am currently building a 331 after a long decision process, and i mean long. i wasnt sure which but then i realized that the trade offs werent worth it for the 347. All that was said by Gearbanger (nicely said), also that it could burn oil from the minute u start it and that it suposedly has a shorter life b/c of stress. Even if is beleived by some (who say its all false or its been corrected) and not others (people who think it does burn oil, etc) i just didnt think it was worth it for what? maybe 15-20 HP?? thats what most told me the difference would be on 2 identical motors but one with a 347 and one 331. Good luck and i hope this made your decision easier
 

90lxcoupe

20+ Year Stangneter
Oct 7, 2003
3,596
350
134
Jan 24, 2004
#12
  • Jan 24, 2004
  • #12
i am planning on putting a dss 331 in my car next year, i wanted to get the 347 originally but i was told that because the 347's stroke is so long that the rod bearings wear out faster.
 

jcp123

New Member
Nov 1, 2003
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Tyler, TX
Jan 24, 2004
#13
  • Jan 24, 2004
  • #13
the 347 will be a torquier engine, capable of seeming a bit 'beefier' from lower rpm's. this is best appreciated in a street car, not a drag car. not sure if there's a huge SOTP difference b/w a 331 and a 347, similarly equipped though. I'd build a 347 since there's no replacement for displacement, but i can definitely see where the lower wear rate and better revvability of the 331 would be an asset
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
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Jan 24, 2004
#14
  • Jan 24, 2004
  • #14
Your not going to see any difference in wear with the 347 over the 331.....the 347 will make a little more torque and a few hp over the 331.
 
C

CobraGT87

Mr. Speed Density
Founding Member
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Jan 24, 2004
#15
  • Jan 24, 2004
  • #15
I thought for sure this mess would of died by now. the myth that 347's burn oil, that the ring land intersec's with the pin etc etc. Does this 347 piston look like theres any intersec problem?. me don't think so.

347 Piston

Technology has come along way since the days of the crawford 347's.

Scott
 

runningmole

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Jun 24, 2002
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Jan 24, 2004
#16
  • Jan 24, 2004
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If 347s were that bad, companies would stop putting them together because of dissatisfied customers.
 

jcp123

New Member
Nov 1, 2003
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Jan 24, 2004
#17
  • Jan 24, 2004
  • #17
yup. that's why i'd be building me a 347...well actually, i'd do a 393w, but that's a different story...
 
9

93cobra12

New Member
Nov 21, 2003
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Jan 26, 2004
#18
  • Jan 26, 2004
  • #18
I chose a 331 for reliabilty, I'd use a 347 if I was building a track car, but my car is for a daily driver.. I did not want to take the chances, plus 10-15 hp can be maid up with a power adder, so why worry about 10-15 hp.. That doesnt mean anything for a street car unless it was track car.. And since it is a street car why worry about it, you'll blow the doors off of 95 % of the cars on street.. Cops wont catch you :oD ... put on a A trim if funds are limited, thats 80-100 rwhp right there.. Your engine will love you !!
 

Sam8950

Founding Member
Mar 13, 2001
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Jan 26, 2004
#19
  • Jan 26, 2004
  • #19
I plan on buying a 347e from CHP. They seem to have conquered most of the problems previously associated with 347s.
 
9

93cobra12

New Member
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Seatte, WA
Jan 26, 2004
#20
  • Jan 26, 2004
  • #20
my buddy had a 347 from CHP two years ago and his motor used to burn a lot of oil.. Thats another reason why i chose 331...
 
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