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  • 1965 - 1973 Classic Mustangs -General/Talk-
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427 side oiler compression reduction

  • Thread starter Thread starter outlaw66
  • Start date Start date Sep 4, 2007
O

outlaw66

New Member
Apr 1, 2005
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Flowood, Ms
Sep 4, 2007
#1
  • Sep 4, 2007
  • #1
I have gotten such good feedback from this site on all things Ford so thought I would throw this out there for some of you big block guys. I just purchased a 67 Fairlane with a 427 side oiler, 2X4's etc etc, which has 12.5 /1 compression. Obviously this engine will not run on pump gas with that kind of compression. The previous owner has been running race gas, I think 110 octane. This was an old 60's era race car but the engine was rebuilt in the late 90's and the 12.5 / 1 pistons were installed at that time. The car is street legal but I need to get the compression down or continue to run race gas at about $8.00 a gallon. I will never race the car again but will take it to car shows and cruise-ins. Can I run 100 octane av-gas safely? What about octane boosters? Regarding head gaskets; are they available, is it even possible and/or is it advisable to run thicker head gaskets to reduce the compression? I remember "back in-the-day" hearing about running thicker head gaskets to reduce compression ratio. It may take a mighty thick head gasket to reduce the compression enough to be able to run pump gas.
I do not want to replace the pistons, but removing the heads would be easy if this is even feasible. Any thoughts or feedback greatly appreciated. AND, I DO have a 66 mustang also. There is a Fairlane website out there but I have not found a forum to answer this question. Any advice appreciated.

Outlaw
 
6

69fecoupe

New Member
Aug 31, 2007
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Sep 4, 2007
#2
  • Sep 4, 2007
  • #2
I would try: http://www.network54.com/Forum/74182/ FE's are their thing.
 
O

outlaw66

New Member
Apr 1, 2005
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0
Flowood, Ms
Sep 4, 2007
#3
  • Sep 4, 2007
  • #3
thanks 69 fe!
 
D

D.Hearne

New Member
Sep 29, 2000
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south louisiana
Sep 6, 2007
#4
  • Sep 6, 2007
  • #4
Best way to do what you want is to tear the motor down and have the piston's domes milled flat. I did this twice back in the 80's with the 427 I had. Both sets of pistons were TRW's and the crowns are thick enough to allow this operation. (one set were stroker 428/427 and the other were regular 427 pistons)
 
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