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Compression, HELP!

  • Thread starter Thread starter werd35
  • Start date Start date May 20, 2010
W

werd35

New Member
Feb 24, 2010
19
0
1
south bend, IN
May 20, 2010
#1
  • May 20, 2010
  • #1
I am building a 351w for my mustang, the block is bored 30 over and it is going to have stock crank, stock rods, and gt40p heads (has 58cc chambers) , and i am planning on running e85 which i heard has around 105 octane. What compression ratio/pistons should i be looking for?
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
95
99
PA
May 21, 2010
#2
  • May 21, 2010
  • #2
If your going to run NA I would put as much as you can, 10.5:1 is safe you'll need a 10cc dish to get around there... I get 10.571:1 on my software using a .040" headgasket, 4.03 bore, 3.5 stroke, 58cc chamber
 
W

werd35

New Member
Feb 24, 2010
19
0
1
south bend, IN
May 22, 2010
#3
  • May 22, 2010
  • #3
thanks, you know what they say, fix it til its broke. going to twist some things more than likely
 

SMOKEDYA

20+ Year Stangneter
Jul 13, 2003
3,637
8
79
Tucson AZ
May 23, 2010
#4
  • May 23, 2010
  • #4
If there is no part number or with the pistons in the block still how can i tell the compression of them? Mine are dished and are stamped on top 40. So i assume mine are 40 over? My 351 is a rebuild with low miles but thats all i know about the block.peace








john
 
W

werd35

New Member
Feb 24, 2010
19
0
1
south bend, IN
May 24, 2010
#5
  • May 24, 2010
  • #5
im getting new ones and there are compression charts.......
 
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