my head cc

[jamerson84]

When I CC'd my 65 200 head I got readings from 46cc's to 49cc's. This is right around the cc I was looking for so I was just wondering how much I should have it milled to just clean up the head? And also would having alot of carbon build up in the combustion chambers effect the cc mesurements? I'm just trying to determine how much to take off the head.
Thanks.

 

[Anonymous]

The guys who sell the Falcon Six handbook have a calculator on their site that will help you figure that out (sorry I don't have the link but look around here and you will find it)

Also read the sticky post at the top of this forum. They talk about the head swap, gasket thickenss, decking the block etc. Do your homework here then talk to your machine shop and go for it.

Good Luck

 

[xctasy]

Mr Collins and co, in all there log headed wisdom, have two of them listed here. Somebodies been looking after you guys...

This icon, aside frombeing a large hypnotic item which keeps website junkies and Ford fanatics in an endless dependant loop on this site, is actually a mysterious portal too ....the jetset world of Ford Six perfromance


In English, just click on the bleading thing, and it'll take you through if you follow your nose
.
http://falconperformance.sundog.net/compcalculator.asp

http://www.bgsoflex.com/auto.html

 

[CZLN6]

Howdy Jamerson84:

Taking into account carbon, this was likely an early, small chamber head of about 52 ccs. Did the engine still have the original steel shim head gasket in place on disassembly. What is the casting#.

You must clean out the carbon and crud build up and cc again. While you're playing with numbers on the compression calculator on our website plug in the beforr and after cc numbers and watch how your compression changes.

I you didn't first clean out the carbon buildup that could account for some of the variation of the volume between cylinders.

I've used everything from oven cleaner to dental pick to clean carbon out. Always lots of elbow grease, scrapers and wire brushes. The carbon build up is the best evidence of the value of polishing the combustion chambers. Carbon won't be able to cling to a smooth surface as easily as a rough one.

The generality we use on late model big chamber heads is that a cut of .010" is roughly equal to a reduction in volume by 2 ccs.

Adios, David

 

[jamerson84]

Well I don't really know if If it's a steel shim type head gasket or not because I haven't seen ether before this one. it has steel around all the cylinders but the rest of it just lookes like gasket if that helps any. The head is a C5 head on the casting number I think thats what you ment if not let me know. Thanks for all the help it's been making a big difference.

 

[CZLN6]

Howdy Back Jammer:

The reason I asked about the head gasket is that if it is an original FoMoCo steel shim gasket, the head is likely an uncut original. If it is an aftermarket it has likely had a valve job some time in the past 38 years. It is very usual for the head rebuilder to do a clean up cut ot .010" or .020" to true the hed surface.

A C5 head casting chamber will typically measure in the 48 to 54 cc range, with the majority in the 51 -52 range.

If you want to be exact, you will need to clean the chambers and re-cc them, buy a gasket set and measure or read the manufacture's compressed thickness. Plug all that into the Compression Calculator on our website (below) and change the ccs until you reach your desired CR goal. It is most accurate to cc the chambers after the valves have been installed for the final time. Cutting the new seats will drop the valves a little, slightly enlarging the chamber.

If you just want to be "In-the-Ballpark" of maintaining a stock CR, have the head milled about .025" to .030".

If you're having a valve job done, do invest in having hardened seats installed, a three angle valve job and back cut the intake valves with a 4th top cut. I would suggest that you reinstall using hardened washers on the head bolts. They help spread the load and are cheap insurance against a bolt bottoming out in its hole.

Adios, David