347 stroker questions

[1991vert]

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

 

[Jeff7477]

taller piston like a 331. 347's like to break cylinder walls.

 

[1991vert]

so the 5.314 has to do with the piston height? is the piston actually taller or is the connecting rod longer/shorter?

 

[Jeff7477]

5.314 is the rod length(shorther than a normal 5.4 347) and the piston is taller

 

[Grn92LX]

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.

 

[Jeff7477]

"When making big power this long rod combination addresses the 347's tendency to break cylinder walls."

From DSS Racing.

 

[Grn92LX]

^ 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.

 

[Jeff7477]

Notice it says big power

 

[Grn92LX]

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]

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]

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?

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.

 

[stroked8e5]

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]

Yep ^

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

 

[5spd GT]

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]

where would i get a pinless 5.315 kit with low compression pistons for use with a blower?

 

[ninjacoupe]

^ 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.

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

 

[5spd GT]

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]

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

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]

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]

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?