All Small Six Performance Build plan for my 1965 Mustang

[pmuller9]

This is a very accurate way to calculate how much needs to be milled off the head to get the desired combustion chamber volume.
Use an inexpensive plastic graduated cylinder.

Here is a .032" thick piece of aluminum I cut out to fit the 300 six combustion chamber.
When you mill the head that is the shape of the area being removed, not the whole 4" circle.
Now all I have to do is place the piece in a graduated cylinder of water and see how much water it displaces.

Here is the cylinder with colored water filled to the 70cc mark.

Here is the cylinder with the combustion chamber aluminum piece folded up to fit inside.

The water is now at the 74.5 cc mark.

Aluminum piece is .032" thick for a 4.5cc displacement or .007" per cc.

If you have a flat top piston that is sitting .010" above the block deck at TDC and a head gasket thickness of .050" with a 3.681" bore,
plan for a 57cc combustion chamber for a 9.5 static compression ratio.

Measure the chamber volumes now and do the above procedure to calculate how much needs to be milled to get the correct chamber volume.

 

[pmuller9]

After you accomplish a 9.5 compression ratio, use a Schneider 140H cam which will give you plenty of power to 5500 rpm.
The Dynamic Compression Ratio will be 7.5 which should work well with medium octane pump gas.

 

[ABrescia]

My confusion comes from the Performance Handbook stating that cc volume on the 200 engine is approximately .010 = 2.4cc. I see by using the method above, the handbook must be only referring to the reduction of vol by milling the block. Also the compression calculator has the compressed gasket as a separate input from the deck clearance. I thought they were included together. -.010 for deck height and .050 for gasket would give me a clearance of .040.

 

[pmuller9]

My confusion comes from the Performance Handbook stating that cc volume on the 200 engine is approximately .010 = 2.4cc. I see by using the method above, the handbook must be only referring to the reduction of vol by milling the block.

The handbook is way off on both counts.
A 200 with a 3.68 cylinder bore displaces 1.744 cc for every .010" of cylinder bore depth.
Do the math and see for yourself.

Also the compression calculator has the compressed gasket as a separate input from the deck clearance. I thought they were included together. -.010 for deck height and .050 for gasket would give me a clearance of .040.

The deck clearance volume and the head gasket volume are calculated separately and are added together during the compression ratio calculations.
A better calculator uses the head gasket bore as an input to calculate head gasket volume since most head gaskets have a larger diameter bore than the cylinder bore.

Compression Ratio Calculator | UEM Pistons

uempistons.com

Yes, a -.010" deck height means the piston is .010" above the block deck at TDC and will give you a .040" piston to head clearance with an .050" head gasket.

 

[bubba22349]

The head gasket has a bore size of 3.810

 

[ABrescia]

The head gasket has a bore size of 3.810

Here are the new numbers, they look better! Will this give me the street performance upgrade that should work on a mid-range octane here in Connecticut ? The next step is to pick out the cam, pistons and adjustable rockers. I assume that my machine shop will know the amount to mill off the head to reach 56.5cc ?

 

[bubba22349]

Here are the new numbers, they look better! Will this give me the street performance upgrade that should work on a mid-range octane here in Connecticut ?

Yes maybe but to know you will need to check out the Dynamic Compression Ratio to. What Camshaft are you thinking of using?

The next step is to pick out the cam, pistons and adjustable rockers. I assume that my machine shop will know the amount to mill off the head to reach 56.5cc ?

Yeah you can't count on the Machine shop knowing how much to mill off, in fact I find that many of the shops don't or won't do much more than a light surface cut on the Head or Block decks, so you will need to be Proactive to get what you want. Also note this info for when your ready to do your Block Deck Milling the Original Ford 200 Pistons had a Dish and were a Compression Height (C.H.) of 1.511, and that all the aftermarket Replacement 200 Pistons with a Dish will have a C. H. of only 1.50. There is also a Ford 200 Australian spec Flat Top Piston available with a C. H. of 1.530. Good luck.

 

[pmuller9]

Here are the new numbers, they look better! Will this give me the street performance upgrade that should work on a mid-range octane here in Connecticut ? The next step is to pick out the cam, pistons and adjustable rockers. I assume that my machine shop will know the amount to mill off the head to reach 56.5cc ?

The first step is to get the block to the shop and have the machinist determine how much the cylinders need to be bored to clean them up.
Then you can select a piston size to meet that measurement.

The machine shop will not know how much to machine off the head to get the combustion chamber volume you need.
That's why I posted the procedure above in post #21 for you to do.

You also need to know which cam you are going to use.
The cam profile will determine the compression ratio.
I suggested the Schneider 140H which limits the compression ratio to 9.5
If you end up with a different cam, then the compression ratio might be different.

 

[ABrescia]

The first step is to get the block to the shop and have the machinist determine how much the cylinders need to be bored to clean them up.
Then you can select a piston size to meet that measurement.

The machine shop will not know how much to machine off the head to get the combustion chamber volume you need.
That's why I posted the procedure above in post #21 for you to do.

You also need to know which cam you are going to use.
The cam profile will determine the compression ratio.
I suggested the Schneider 140H which limits the compression ratio to 9.5
If you end up with a different cam, then the compression ratio might be different.

Makes sense, I was looking to build top down but now as I’m reading the posts I see how the progression can start with the block. Thanks for the old school way of way of finding the chamber volume .

 

[pmuller9]

Makes sense, I was looking to build top down but now as I’m reading the posts I see how the progression can start with the block. Thanks for the old school way of way of finding the chamber volume .

In most cases the piston is used to adjust the compression ratio either by piston dish volume and/or piston height so you start by completing the cylinder head first to get the chamber volume then follow it up with the short block.
This a top to bottom build

In your case, the piston has a flat top and is being set .010" above the block deck to get a .040" quench distance as a given.
Once that is done successfully, then the head chamber volume is adjusted for the correct compression ratio based on the cam profile.
The head is completed after the short block making it a bottom to top build.

You will need to purchase a few measuring tools to do this job.

Are you going to assemble the entire engine?

 

[78_200_C4]

Why don't you use dished pistons. Doing this mill the head .055-065" That will give you close to 9-1 compression.

That what I have. Dished 78 Fairmont pistons with a .060 milled D7 head. I run the cheapest gas available.