So as I wait on my head to be machined, I've started to turn my thoughts towards what I'd like to do with the block. So the items that I'm looking to address in this game are:
1) Rod/Stroke Ratio
2) Rod Angle
3) Squish
Now, the first 2 really go hand in hand and can probably be considered one item. But for arguments sake I'm going to leave them separate. My end goal is to increase the Rod/Stroke ratio, decrease the Rod Angle, and shoot for a nominal 0.040" squish band.
To start things off, I created a tool that I can use to plug and play different aspects of my engine build to see what the expected results will be. This script reads a text file input so I can save different configurations off. Right now, it just spits the output onto the tool workspace. In this case, I'm using Matlab but this should also run in other math programs such as Octave with no modifications to the syntax.
I ran the numbers on the stock 200. For this exercise, let's assume we're using a stock large log head with the 62cc chambers and a coreteco gasket with a 0.44 compression height. This is where the "average" refreshed engine would be without machine work. Now bear with me on the cam specs. I haven't completely validated those numbers, so the DCR could be off. The output looks like this:
================================================
INPUT - BUILD PARAMETERS
================================================
Block Specifications:
Cylinder Bore = 3.68 in
Rod Length = 4.715 in
Stroke = 3.126 in
Piston Dish Volume = 6.5 cc
Piston Compression Height = 1.511 in
Cylinder Head Specifications:
Combustion Chamber Volume = 62 cc
Gasket Diameter = 3.81 in
Gasket Crush Height = 0.044 in
Camshaft Specifications:
Intake Duration = 252 deg
Lobe Separation Angle = 102 deg
Ground-in Advance = 0 deg
Camshaft Installation Advance = 0 deg
Resulting Intake Closing = 48 deg
================================================
OUTPUT
================================================
Engine Displacement = 200 in^3
Rod to Stroke Ratio = 1.51:1
Rod Angle = 19.36 deg
Resulting Deck Height = 0.019 in
Squish Distance = 0.063 in
Static Compression Ratio = 7.80:1
Dynamic Compression Ratio = 6.99:1
1) Rod/Stroke Ratio
2) Rod Angle
3) Squish
Now, the first 2 really go hand in hand and can probably be considered one item. But for arguments sake I'm going to leave them separate. My end goal is to increase the Rod/Stroke ratio, decrease the Rod Angle, and shoot for a nominal 0.040" squish band.
To start things off, I created a tool that I can use to plug and play different aspects of my engine build to see what the expected results will be. This script reads a text file input so I can save different configurations off. Right now, it just spits the output onto the tool workspace. In this case, I'm using Matlab but this should also run in other math programs such as Octave with no modifications to the syntax.
I ran the numbers on the stock 200. For this exercise, let's assume we're using a stock large log head with the 62cc chambers and a coreteco gasket with a 0.44 compression height. This is where the "average" refreshed engine would be without machine work. Now bear with me on the cam specs. I haven't completely validated those numbers, so the DCR could be off. The output looks like this:
================================================
INPUT - BUILD PARAMETERS
================================================
Block Specifications:
Cylinder Bore = 3.68 in
Rod Length = 4.715 in
Stroke = 3.126 in
Piston Dish Volume = 6.5 cc
Piston Compression Height = 1.511 in
Cylinder Head Specifications:
Combustion Chamber Volume = 62 cc
Gasket Diameter = 3.81 in
Gasket Crush Height = 0.044 in
Camshaft Specifications:
Intake Duration = 252 deg
Lobe Separation Angle = 102 deg
Ground-in Advance = 0 deg
Camshaft Installation Advance = 0 deg
Resulting Intake Closing = 48 deg
================================================
OUTPUT
================================================
Engine Displacement = 200 in^3
Rod to Stroke Ratio = 1.51:1
Rod Angle = 19.36 deg
Resulting Deck Height = 0.019 in
Squish Distance = 0.063 in
Static Compression Ratio = 7.80:1
Dynamic Compression Ratio = 6.99:1