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

Need some help ASAP

  • Thread starter Thread starter TimGT
  • Start date Start date Sep 1, 2009
T

TimGT

Founding Member
May 2, 2001
201
0
0
Santa Fe, New Mexico
Sep 1, 2009
#1
  • Sep 1, 2009
  • #1
Ok so I haven't posted here in a really long time since I no longer have a Mustang.

So I got these heads after this company screwed up my motor. Well they had only opened one of them to show me and I left the other one wrapped up. Well the one they showed me was a PI CNC'd head that look brand new. Well after about 2 years of them sitting in the garage I decided to unwrap them both so I could take pictures because a guy wanted to buy them. I unwrap them both and the other one looks used and is a non-PI head The reason I didn't unwrap them both right away was because it took them a year and half for them to get me a short block and 2 years to get me the heads and by then I had already sold the car and wanted nothing to do with cars at all.

Well my question is, does it matter if one is PI and the other is a non-PI head if they were both CNC'd?
 

SaleenGT2001

Well-Known Member
Jul 18, 2005
2,811
4
58
Four Oaks NC
Sep 2, 2009
#2
  • Sep 2, 2009
  • #2
the compression ratio will be different with a non pi head.
 

trinity_gt

10 Year Member
Jan 31, 2003
3,125
81
99
Canada
Sep 2, 2009
#3
  • Sep 2, 2009
  • #3
Even CNCd, the chamber shapes are different, the port volumes are different, flow characteristics are different etc. So I'll say "yes, it matters."
 

eliteJAE

Member
May 29, 2007
0
1
16
Stanford University
Sep 2, 2009
#4
  • Sep 2, 2009
  • #4
Wow I would crapped a brick, they basically screwed you multiple times and got away with it :/ it matters man.
 
T

TimGT

Founding Member
May 2, 2001
201
0
0
Santa Fe, New Mexico
Sep 2, 2009
#5
  • Sep 2, 2009
  • #5
Well the chambers look like they were CNCd too, I'll post up some pics later on tonight. The only other thing I could think of that would be different is the valve cover holes.
 
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