Thanks. Now I have to figure out how to get that program to run on my Mac.
| Slant Six Forum https://slantsix.org/forum/ |
|
| Dynamic compression ratio calculator https://slantsix.org/forum/viewtopic.php?t=38542 |
Page 1 of 1 |
| Author: | Reed [ Thu Jan 07, 2010 1:05 pm ] |
| Post subject: | Dynamic compression ratio calculator |
Anybody know of a good yet free online dynamic compression ratio calculator? All I can find are ones for v-8s. Thanks. |
|
| Author: | gmader [ Thu Jan 07, 2010 1:23 pm ] |
| Post subject: | |
http://members.uia.net/pkelley2/DynamicCR.html |
|
| Author: | Reed [ Thu Jan 07, 2010 1:30 pm ] |
| Post subject: | |
Thanks. Now I have to figure out how to get that program to run on my Mac.
|
|
| Author: | Reed [ Thu Jan 07, 2010 1:47 pm ] |
| Post subject: | |
Okay, I got it to work, and I calculated my dynamic stroke length, my cam timing and overlap, and my static compression. But how do I turn any of these numbers into a dynamic compression ratio? |
|
| Author: | Reed [ Thu Jan 07, 2010 7:15 pm ] |
| Post subject: | |
Okay, nevermind.  I guess it helps to read the instructions on the webpage. 
|
|
| Author: | DusterIdiot [ Thu Jan 07, 2010 7:21 pm ] |
| Post subject: | Yep... |
I use that one consistently, and it's a good tool for looking over "future builds". How'd your engine build turn out? -D.Idiot |
|
| Author: | Reed [ Thu Jan 07, 2010 7:40 pm ] |
| Post subject: | |
I am finishing up the last few calculations for getting the head decked to achieve an 8.2 dynamic compression ratio. I would appreciate it if someone could check my math. I am using the a cam ground to match the Erson RV10 profile. The cylinders are .030 oversize. I have 56 cc combustion chambers (surprisingly they are all the same). I have calculated that I need 40 cc combustion chambers to bump the dynamic compression ratio from the current 6.9 up to 8.2. In other words, I need to remove 16 cc of volume from the combustion chambers. Assuming the lowest portion of the combustion chamber is a perfect circle (which I know isn't true due to the factory notched for the valves, but it is close enough), I need to use the following formula to calculate how much I need shaved off: The volume of the cylinder = pie X radius of the cylinder squared X height of the cylinder I need to remove 16 ccs, so 16 = pie X radius squared X height Pie is a constant 16 is a known variable radius = 3.4 inches / 2 (or, to keep it simple and to keep the units constant, 8.628 cm/2). So, R=4.314cm So, Height cm = 16/ (pie X (4.314 squared)) Height cm = .273659058471 cm So Height inches = .1077397868 SO! I need to mill .100 inches off the head. Right? |
|
| Author: | DusterIdiot [ Thu Jan 07, 2010 8:04 pm ] |
| Post subject: | Let's see... |
Quote: Milling the Slant Six cylinder head .0066" gives a 1cc decrease in combustion chamber size
I just would cheat and use Doc's number from the stroker article (It hasn't let me down yet!!!)so 16CC * .0066 =.1056.... .1077 is on the money... .100 would be fine... -D.Idiot |
|
| Author: | Reed [ Thu Jan 07, 2010 8:08 pm ] |
| Post subject: | |
 Cool! Thanks Rob! Good to know I still gots my math skills! |
|
| Author: | Al T [ Fri Jan 08, 2010 11:37 am ] |
| Post subject: | Online Dynamic Compression Calculators |
http://www.rbracing-rsr.com/calculations.htm Here's the one I used Reed. |
|
| Author: | Reed [ Fri Jan 08, 2010 11:39 am ] |
| Post subject: | |
Thanks Al! |
|
| Page 1 of 1 | All times are UTC-08:00 |
| Powered by phpBB® Forum Software © phpBB Limited https://www.phpbb.com/ |
|