134 vs 172 head

[PitCrew]

I'm taking apart my 172, and am going to modify it some for tractor pulling.

I have cc d the 172 head, now know deck height, rod specifications, position in the bore, crank to cam clearance, and most of the other information required to begin a thought out design to increase cubic inches and raise compression.

My question is how much smaller is the combustion chamber, intake/exhaust runner and valves on a 134 head as compared to a 172 head?

Thanks in advance

 

[john_Bud]

If you want more in3's, use 192 pistons. Should be able to over bore to reach that size. May want to sono check the walls first....


jb

 

[PitCrew]

What is the bore size of a 192 (4.125)?

Do I bore out the 3.90 sleeves or remove them and run against the block wall.

What is the OD of the sleeve ?

Thanks,

Eric

 

[Fordfarmer]

This topic has been covered before, and if I remember right, the 172 doens't have enough cylinder wall thickness to go to the bore for a 192 piston, even if you pull the sleeves and run on the block wall. There is a "super power overbore" rebuild kit for doing this, though. Available from the parts section of this site. Gives you more cubes, but not 192.
A quick check of my parts manual indicates that the 172 and 134 engines used the same size valves, except for the diesels. I can't say about runner length, but would assume htey're about the same. Main difference I know of is the smaller combustion chamber on the 134 head (which might mean slightly longer runners on the 134's).

 

[john_Bud]

No sleeve, bore in block. As Fordfarmer said, it may be too thin. Sonic check the walls first and see if it can be done.

jb

 

[PitCrew]

Thanks for the responses, I guess I'll just pull a sleeve and see where I'm at.

I'll go to Ripee's in Farmington Mo. and see if he will let me cc a 134 head, or I'll just buy a core and start from there.

I was just looking to get the information for the math for increased compression, but apparently no one has it