dynamic compression 10.05:1
Thread Starter
|
Cruiser
Joined: Jul 2010
Posts: 151
Likes: 0
From: Monticello Indiana
dynamic compression 10.05:1
Knowing what dynamic compression is and how it relates to intake vale timing and throwing into the mix the squish area needing to be in a precise range.... is any tuners out there getting away with a dynamic of 10.05 area and squish in the .035 range? Seems like this is going to be problematic in the hot seasons with out taking major ignition timing out of it. Please jump in and help so my buddy doesn't hurt his engine this summer when the heat rolls in. He is loving the dyno numbers in low rpm but was done in cool months in the fall.
I am hoping it will be fine and his numbers rock just don't wanna see any damage to his bike.
late 2011 twin cam, static 10.5, se-255 cams, head work, and 58mm t-body, no cats, very good exhaust
I am hoping it will be fine and his numbers rock just don't wanna see any damage to his bike.
late 2011 twin cam, static 10.5, se-255 cams, head work, and 58mm t-body, no cats, very good exhaust
Last edited by Raccerx67; Feb 18, 2013 at 07:03 PM. Reason: typo
Intermediate
Joined: Nov 2008
Posts: 45
Likes: 0
Knowing what dynamic compression is and how it relates to intake vale timing and throwing into the mix the squish area needing to be in a precise range.... is any tuners out there getting away with a dynamic of 10.05 area and squish in the .035 range? Seems like this is going to be problematic in the hot seasons with out taking major ignition timing out of it. Please jump in and help so my buddy doesn't hurt his engine this summer when the heat rolls in. He is loving the dyno numbers in low rpm but was done in cool months in the fall.
I am hoping it will be fine and his numbers rock just don't wanna see any damage to his bike.
late 2011 twin cam, static 10.5, se-255 cams, head work, and 58mm t-body, no cats, very good exhaust
I am hoping it will be fine and his numbers rock just don't wanna see any damage to his bike.
late 2011 twin cam, static 10.5, se-255 cams, head work, and 58mm t-body, no cats, very good exhaust
Need some better detail on the build , what type of tuner?
Last edited by valleyracinginc; Feb 18, 2013 at 08:38 PM.
Thread Starter
|
Cruiser
Joined: Jul 2010
Posts: 151
Likes: 0
From: Monticello Indiana
Thats the numbers i got using this calc on the link below
http://www.rbracing-rsr.com/comprAdvHD.htm
Another one was a touch lower here
Static compression ratio of 10.5:1.
Effective stroke is 3.99 inches.
Your dynamic compression ratio is 9.53:1 .
Your dynamic cranking pressure is 199.09 PSI.
http://www.wallaceracing.com/dynamic-cr.php
both seem to be high numbers from reading lots of articles on bikes, even high compared to considered acceptable for automotive builds. Just looking for thoughts
Thanks
Doug
http://www.rbracing-rsr.com/comprAdvHD.htm
Another one was a touch lower here
Static compression ratio of 10.5:1.
Effective stroke is 3.99 inches.
Your dynamic compression ratio is 9.53:1 .
Your dynamic cranking pressure is 199.09 PSI.
http://www.wallaceracing.com/dynamic-cr.php
both seem to be high numbers from reading lots of articles on bikes, even high compared to considered acceptable for automotive builds. Just looking for thoughts
Thanks
Doug
Intermediate
Joined: Nov 2008
Posts: 45
Likes: 0
Thread Starter
|
Cruiser
Joined: Jul 2010
Posts: 151
Likes: 0
From: Monticello Indiana
Using your link going with the .05 intake closing and adding 15 as a ballpark seat cloing figure since I don't have that specification and cant find it, it still ends up at 9.68:1 dynamic compression ratio. Everything I have ever read over the last 10 years regarding dynamic is 8.5 is the safe max range on aluminum heads. I know you can work over this number with kepping a high velocity intake charge and tight squish numbers but that just seems like its going to be a problem for him once it gets hot this summer. Thankyou for the links too btw, I appreciate it alot!!!!
Doug
Doug
Thread
Thread Starter
Forum
Replies
Last Post
