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347 stroker questions

  • Thread starter Thread starter 1991vert
  • Start date Start date Aug 30, 2005
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1991vert

10 Year Member
Feb 27, 2004
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Ludlow, MA
Aug 30, 2005
#1
  • Aug 30, 2005
  • #1
what's the difference between a regular 347 stroker and one with a 5.314? people keep telling me "oh it's like a 331, but with a 347 crank" im getting confused. i just dont understand how it can be "like a 331", yet be a 347


someone please point me in the right direction!!

links to web pages explaining this would do wonders. i need to do my homework on this stuff
 
J

Jeff7477

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Jul 2, 2001
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Lincoln, Nebraska USA
Aug 30, 2005
#2
  • Aug 30, 2005
  • #2
taller piston like a 331. 347's like to break cylinder walls.
 

1991vert

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Feb 27, 2004
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#3
  • Aug 30, 2005
  • #3
so the 5.314 has to do with the piston height? is the piston actually taller or is the connecting rod longer/shorter?
 
J

Jeff7477

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#4
  • Aug 30, 2005
  • #4
5.314 is the rod length(shorther than a normal 5.4 347) and the piston is taller
 

Grn92LX

Fidanza Man!
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#5
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The 347 kit with the probe 5.315" rods use the SAME probe pistons as a 331. The compression height is taller giving you more "meat" but at the same time a heavier piston. I went 5.315" rod combo only because I didn't wanna wait for the 5.4" as they were on a long ass backorder. My builder (Rick 91GT) called me and asked is I minded switching. I preferred the 5.4" rods, but I wanted my motor this millenium

Like I said, I prefer the 5.4" rod set up, but for your typical street car, it doesn't matter. 347's don't break cyl walls.
 
J

Jeff7477

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#6
  • Aug 30, 2005
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"When making big power this long rod combination addresses the 347's tendency to break cylinder walls."

From DSS Racing.
 

Grn92LX

Fidanza Man!
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#7
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^ LMFAO ^

Marketing gets the best of us sometimes Talk to REAL builders if you're serious. Only thing my 347 has a tendency to do is suck up gas.
 
J

Jeff7477

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#8
  • Aug 30, 2005
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Notice it says big power
 

Grn92LX

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#9
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My friends should be near 600hp once it gets tuned. It hasn't broke yet

Fwiw, Its not you I was laughing at, it was dss's piss more attempt at marketing and the sad fact that people believe that garbage.
 

1991vert

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#10
  • Aug 30, 2005
  • #10
it's going in a dart block so would that 5.4 break a dart block cylinder wall?

also someone told me to have it zero balanced, what does that mean? i thought 302 based engines were externally balanced?
 

Grn92LX

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1991vert said:
it's going in a dart block so would that 5.4 break a dart block cylinder wall?

also someone told me to have it zero balanced, what does that mean? i thought 302 based engines were externally balanced?
Click to expand...

347's don't break cyl walls.

Stock 302 cranks, aftermarket cast steel cranks and some forged cranks go external balance. Good aftermarket forged cranks can go internal. If you're paying for a good block, do a good crank the right way, 0 balance.
 
S

stroked8e5

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Jun 18, 2005
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#12
  • Aug 30, 2005
  • #12
331 is 3.25" stroke and the 347 is 3.4" stoke. The 5.315" rod combo was to get the piston pin out of the oil ring groove.
 

Grn92LX

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Yep ^

Just don't forget some 331 kits have the pin through the oil ring (not that it makes a difference)
 

5spd GT

"the 5.0 owns all"
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#14
  • Aug 30, 2005
  • #14
A 347 in itself doesn't break cylinder walls but does put more sidewall pressure on the block. If a 331 is on the borderline of cracking a block...then the 347 could do it more likely than a 331.

I wouldn't worry about a Dart breaking

Edit: I would rather have a "pinless" ring than one with a pin. It makes a difference in longevity.
 

1991vert

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Feb 27, 2004
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#15
  • Aug 31, 2005
  • #15
where would i get a pinless 5.315 kit with low compression pistons for use with a blower?
 

ninjacoupe

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Jul 6, 2003
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Aug 31, 2005
#16
  • Aug 31, 2005
  • #16
Grn92LX said:
^ LMFAO ^

Marketing gets the best of us sometimes Talk to REAL builders if you're serious. Only thing my 347 has a tendency to do is suck up gas.
Click to expand...

Thats nothing. My 347 can call the Po'lice from over a mile away
 

5spd GT

"the 5.0 owns all"
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Aug 31, 2005
#17
  • Aug 31, 2005
  • #17
DSS isn't a "fake" builder...and don't you think "builders" are going to tell you about the pros of the 347. They make more money building 347's than a 331. Think about it...

Why do you think companies like CHP, DSS, and the other builders would sell/make/assemble 331's and 347's if they were had all the same pros/cons but the 347 made more power. Think about it There are different stroker trends because they have different pros/cons and it is left up to the actual user to decide. Very simple...
 

5spd GT

"the 5.0 owns all"
Founding Member
Aug 7, 2002
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99
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Aug 31, 2005
#18
  • Aug 31, 2005
  • #18
ninjacoupe said:
Thats nothing. My 347 can call the Po'lice from over a mile away
Click to expand...

My "302" can do that (with 160k on it nearly)... The cubes matter?

My buddy called me (lives over a mile and a half away) and said he could hear me pulling out of my driveway He knew it was me...

I have also saved my neighbor's job a few times when his alarm didn't go off when I would go to school. He thanked me for it. Yeah it was the exhaust.

To bad the state troopers didn't like me speeding the other night...yeah I got a ticket coming home from a supercharger install - go figure
 

1991vert

10 Year Member
Feb 27, 2004
1,103
7
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Ludlow, MA
Aug 31, 2005
#19
  • Aug 31, 2005
  • #19
lucky you got away with just speeding. im sure if he wanted to be a jerk he'd take a look under the car at the exhaust .

so does probe or scat make these pinless stroker kits?
 

Grn92LX

Fidanza Man!
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#20
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Dave, my builder charges the same price for a 331 and a 347 He didn't make an extra dime selling me a 347 instead of a smaller 331. The "pinless" kit does not make a difference in longevity. Remember the 185k 3.40 stroke 5.4" rod engine I've mentioned built by that guy over on hardcore? Your engine doesn't even have 185k trouble free non blow by/oil issues

Ninja, thats a very odd 347 you got there

1991vert, one thing I forgot to mention, but i'm sure you already know, with the dart block you can go big on the bore. Don't bore it .030, go big on the bore and go like 360". You can get the 5.315" stuff from chp/probe. Ask if their forged cranks can go 0 (internal) balance. If not, don't use it. Why put an external balance in a $2000 dart block?
 
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