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347ci bored .30 over is a 350 right?

  • Thread starter Thread starter cathartic
  • Start date Start date Aug 21, 2004

cathartic

Founding Member
Jan 27, 2002
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Ca
Aug 21, 2004
#1
  • Aug 21, 2004
  • #1
if a 302 is a 306 30 over then a 347 30 over should be a 350 right?
 

hllon4whls

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Founding Member
Jan 17, 2002
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Covington
Aug 21, 2004
#2
  • Aug 21, 2004
  • #2
A 342 bored +.030 is a 347.
 

UMDSmith

Member
Feb 10, 2004
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Salisbury, Maryland
Aug 21, 2004
#3
  • Aug 21, 2004
  • #3
by the math a 347 bored out should be a 351, but I thought a 347 was already bored out, so going 60 over would probably weaken it too much.
 

85_SS_302_Coupe

it sucks (I know) to be on the receiving end
15 Year Member
Nov 11, 2003
6,945
1,598
223
Northern KY
Aug 21, 2004
#4
  • Aug 21, 2004
  • #4
You don't bore out a bored out motor.. It would be a 302 bored out to a 350....which is possible if you've got a Dark block or 302R or something equally strong. I've seen 357s out of a 302.
 

88stangmangt

Active Member
Nov 25, 2003
2,332
1
48
Stafford,VA
Aug 21, 2004
#5
  • Aug 21, 2004
  • #5
double boreing a production block...........
 

bluevenom867

I will have images of molesting stuffed animals in
Dec 15, 2003
1,704
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0
St.Petersburg,FL
Aug 22, 2004
#6
  • Aug 22, 2004
  • #6
Here is how you can get displacment:
BoreXBoreXStrokeX.7854XNo. of Cyclinders
Ex:
4X4X3X.7854X8= 301.5936
So you see our 302 is actually a
rounded-up 301
 

bluevenom867

I will have images of molesting stuffed animals in
Dec 15, 2003
1,704
1
0
St.Petersburg,FL
Aug 22, 2004
#7
  • Aug 22, 2004
  • #7
Try it on your own calculator.
 

cathartic

Founding Member
Jan 27, 2002
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Ca
Aug 22, 2004
#8
  • Aug 22, 2004
  • #8
its a black block new from Probe
 
K

kystang1889

New Member
Dec 29, 2002
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ky
Aug 22, 2004
#9
  • Aug 22, 2004
  • #9
I 347 is a 302 bored .30 over with a 3.4 inch stroke with out boring the block its a 342
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Aug 22, 2004
#10
  • Aug 22, 2004
  • #10
bluevenom867 said:
Here is how you can get displacment:
BoreXBoreXStrokeX.7854XNo. of Cyclinders
Ex:
4X4X3X.7854X8= 301.5936
So you see our 302 is actually a
rounded-up 301
Click to expand...

correct. for someone that might ask where the constant 0.7854 was derived from, it is pi/4
 

TT91

Active Member
May 23, 2003
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Paramus, NJ
Aug 22, 2004
#11
  • Aug 22, 2004
  • #11
cathartic said:
its a black block new from Probe
Click to expand...
a what?
 

cathartic

Founding Member
Jan 27, 2002
220
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0
Ca
Aug 22, 2004
#12
  • Aug 22, 2004
  • #12
ok, it is not bored over twice. i was mistaken. the block came from Probe it is a production block and was jet black. i doubt there is a difference I was just stating its a new block and is black is all.
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Aug 22, 2004
#13
  • Aug 22, 2004
  • #13
Note: bores beyond 4.03 on a stock Ford block shouldn't be attempted unless the cylinder walls have been ultrasonically tested and have enough meat for the overbore; many of the aftermarket blocks such as the "Dark" block mentioned above (this is probably the "Dart" block) have more meat allowing larger bores.

302 bored .030 over is 4.03 bore X 3.00 stroke = 306.13 ~ 306
302 bored .040 over is 4.04 bore X 3.00 stroke = 307.65 ~ 308
302 bored .060 over is 4.06 bore X 3.00 stroke = 310.70 ~ 311
302 with 3.25" stroker crank is 4.00 bore X 3.25 stroke = 326.73 ~ 327
302 with 3.25" stroker crank and .030 overbore is 4.03 X 3.25 = 331.64 ~ 331 (actually we should call this a 332, but everyone refers to it as a 331; if we're gonna call it a 331 we should start calling our stock engines a 301 )
302 with 3.25 stroker crank and .040 overbore is 4.04X3.25 = 333.29 ~ 333
302 with 3.25 stroker crank and .060 overbore is 4.06X3.25 = 336.60 ~ 337
302 with 3.4 stroker crank is 4.00X3.4 = 341.80 ~ 342
302 with 3.4 stroker crank and .030 overbore is 4.03X3.4 = 346.95 ~ 347
302 with 3.4 stroker crank and .040 overbore is 4.04X3.4 = 348.67 ~ 349
302 with 3.4 stroker crank and .060 overbore is 4.06X3.4 = 352.14 ~ 352

Let's start it here guys - from now on we refer to a 332 as a 332 instead of a 331. Whadya say?
 

Michael Yount

Mustang Master
Apr 10, 2002
9,039
6
79
Charlotte, NC
Aug 22, 2004
#14
  • Aug 22, 2004
  • #14
"....its a new block and is black is all."

Would that be the "Dark" block that 85SS referred to?

Sorry, couldn't resist....
 

cathartic

Founding Member
Jan 27, 2002
220
0
0
Ca
Aug 22, 2004
#15
  • Aug 22, 2004
  • #15
yes, exactly
 
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