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  • SN95 4.6L Mustang Tech

RAISING COMPRESSION WITH NPI HEADS???

  • Thread starter Thread starter Mac-man
  • Start date Start date Apr 22, 2004
M

Mac-man

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Nov 7, 2003
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Apr 22, 2004
#1
  • Apr 22, 2004
  • #1
a friend of mine has a 98 gt and is going to have his heads ported and polished.....and also wants to mill the heads to get about 10.5:1 compression...does anyone know how much they would have to be milled or where i could find out???
 

DBMSTNG

I fantasize about it being BIG!
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Apr 23, 2002
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Apr 22, 2004
#2
  • Apr 22, 2004
  • #2
Mac-man said:
a friend of mine has a 98 gt and is going to have his heads ported and polished.....and also wants to mill the heads to get about 10.5:1 compression...does anyone know how much they would have to be milled or where i could find out???
Click to expand...

you do not want to mill the heads. 1st of all, there isn't much valve clearance. 2nd, you will mess up the cam timing. .020" is the most that you could go, and that won't be worth it. no offense, but 10.5 compression on the NPI heads is a waste of effort. tell your friend to break down and get PI heads.
 
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