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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

Boring a 5.0 +.060

  • Thread starter Thread starter 50FoxBodyGT
  • Start date Start date Aug 28, 2006

50FoxBodyGT

Member
Aug 24, 2006
74
4
9
Memphis
Aug 28, 2006
#1
  • Aug 28, 2006
  • #1
Hey guys,
How do feel about boring a 5.0 to +.060? Has anyone had any good/bad experiences doing this? Is it just too much or will I be okay?
 

BlownFiveLiter

have car, will race....wait, it doesn't run
15 Year Member
Nov 29, 1999
3,133
18
108
Chicagoland
Aug 28, 2006
#2
  • Aug 28, 2006
  • #2
I'm pretty sure you'd really be pushing it on a factory block. The figure I've always heard for a stock block is .030 over, .040 being the absolute max before needing to have it sleeved or having to pick up a new block.
 

85ragtop

BTW, I like dudes.
10 Year Member
Nov 29, 1999
823
475
123
NC
Aug 28, 2006
#3
  • Aug 28, 2006
  • #3
I don't know about the 302. My 351 is .060 over. No probs so far.
 

50FoxBodyGT

Member
Aug 24, 2006
74
4
9
Memphis
Aug 28, 2006
#4
  • Aug 28, 2006
  • #4
I think the 351 might have thicker walls, though. Not sure on that. What's the issue with over-boring? Is it that the engine will run hot or am I going to bust a rod or something through the cylinder wall?
 
R

R2D2

Aug 28, 2006
#5
  • Aug 28, 2006
  • #5
If your chosen machinist doesnt have the ability to sonic check the block and tell you the numbers then run away. Some will take, most wont. Unless your .040 now there is no advantage to taking it from 4.0-4.030 bore to 4.060. Yes the issue is the thrust side of the cylinder.
 

Woodrow

Founding Member
May 19, 2002
183
0
0
Atlanta/Auburn
Aug 28, 2006
#6
  • Aug 28, 2006
  • #6
I have a .070 motor that I run with no issues. I wouldnt advise it on the street though.
 

Shakin66

Founding Member
Jan 19, 2001
628
1
19
Waycross, Ga / Lake James, NC
Aug 28, 2006
#7
  • Aug 28, 2006
  • #7
I have bored two 302's to 60o/s and both ran hot....I swore i'd never do it again the second time.
 
B

bentley429

Banned
Nov 25, 2004
528
3
0
Connecticut
Aug 28, 2006
#8
  • Aug 28, 2006
  • #8
StangGT1995 said:
I'm pretty sure you'd really be pushing it on a factory block. The figure I've always heard for a stock block is .030 over, .040 being the absolute max before needing to have it sleeved or having to pick up a new block.
Click to expand...

Exactly, 308 is the biggest I'd go on a stock 302.
 

dastang2

Active Member
Dec 11, 2003
2,020
0
46
tx
Aug 28, 2006
#9
  • Aug 28, 2006
  • #9
i have done it with no problems. yes it runs hotter at around 260-290 on a stock 3 core truck radiator but an aluminum radiator and electric fan would help a lot. i still have the pistons from it since the bearings didn't last.(because i didn't get the block allign honed
 
P

Phatt_daddy

Member
Apr 22, 2005
219
1
19
Hytop, AL
Aug 28, 2006
#10
  • Aug 28, 2006
  • #10
the stock engine in my '87 was .060 and I had no problems w/ electric fan and stock rad.....until I killed the compression rings. Finally got around to puling the pistons out and 6 out of 8 the top ring fell off into 4 pieces
 
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