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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

lowering compression

  • Thread starter Thread starter jcint
  • Start date Start date Jul 20, 2005

jcint

Member
Mar 30, 2005
168
2
16
wellington florida
Jul 20, 2005
#1
  • Jul 20, 2005
  • #1
So if i port and polish my PI heads it will lower my compression? Will i need to change my spings and cams if i get this done? i live in south florida, anyone have an estimate on how much polishing porting heads will run me?
 

ADRENLN

Active Member
Apr 16, 2003
2,342
3
49
NJ
Jul 21, 2005
#2
  • Jul 21, 2005
  • #2
well i just made a thread about the same thing a couple days ago. you be better off searching for my thread, but what i gathered is: that p&p wont readdy change compression unless its a huge port. i beleive compression will drop a little. if the porter messes with the combustion chambers then that will also change the compression. from what i understand, it compression change is minamal to what you would gain so it really dont matter.

my heads are in the works right now.
 

ADRENLN

Active Member
Apr 16, 2003
2,342
3
49
NJ
Jul 21, 2005
#3
  • Jul 21, 2005
  • #3
i think you only have to change your springs if you do cams.
 
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