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Feb 15, 2012 | 09:01 PM

#41

lionsm13

Seasoned HDF Member

Joined: Oct 2007

Posts: 56,052

Likes: 88,134

From: Western South Dakota

Thanx for the update, been sittin' on the edge of my seat...

Feb 15, 2012 | 10:13 PM

#42

BackRoader

Road Master

Joined: May 2008

Posts: 1,096

Likes: 107

From: Joplin, MO

Added an Andrews 21 last summer. I love it. A little bit of extra pull. Key words here are "little bit". Cam change is a nice extra bump in power, but it does not turn your bike into a beast. Just a little extra pulling power, so don't expect huge gains here. As they say, "there's no replacement for displacement".

Feb 16, 2012 | 06:03 AM

#43

tx-skydiver

Thread Starter

Road Warrior

Joined: Mar 2009

Posts: 1,326

Likes: 2

From: scurry, TX

Quote:

Originally Posted by lionsm13

Thanx for the update, been sittin' on the edge of my seat...

I know, right? I'm sure everyone was. Consider this my public service for the day.

Feb 16, 2012 | 07:56 AM

#44

weride7/7

Advanced

Joined: Oct 2011

Posts: 55

Likes: 0

From: St. Petersburg

255's here. Very adequate and reliable.

Feb 16, 2012 | 08:11 AM

#45

Sash302

Road Warrior

Joined: Mar 2009

Posts: 1,837

Likes: 46

From: Macomb MI

I vote for SE-204 great little cam

Feb 16, 2012 | 09:49 AM

#46

drew4jan

Road Master

Joined: Apr 2010

Posts: 845

Likes: 45

From: Tucson, AZ

I have a set of SE255's sitting in the garage. Just waiting for push rods and gasket kit to get started.

Feb 16, 2012 | 05:22 PM

#47

tx-skydiver

Thread Starter

Road Warrior

Joined: Mar 2009

Posts: 1,326

Likes: 2

From: scurry, TX

Quote:

Originally Posted by Sash302

I vote for SE-204 great little cam

Thats actually what I meant. I think I typed 254 by accident.

Feb 16, 2012 | 06:45 PM

#48

ocezam

Road Master

Joined: Apr 2011

Posts: 1,145

Likes: 98

From: Colorado Springs

Quote:

Originally Posted by BackRoader

Added an Andrews 21 last summer. I love it. A little bit of extra pull. Key words here are "little bit". Cam change is a nice extra bump in power, but it does not turn your bike into a beast. Just a little extra pulling power, so don't expect huge gains here. As they say, "there's no replacement for displacement".

Well if your talking a stock 88", like your sig suggests, then yeah the performance boost of a cam upgrade will be negligible. But on a 96" or better yet a 103", the performance gain is MUCH more noticeable.

The difference really isn't the 8 and 7 cubic inch bump. It's the compression difference between the engines. I believe a stock 88" has 9:1 compression, the 96" has 9.2:1 compression, and the 103" has 9.6:1 compression. Not huge differences, but it does make a pretty big difference filling the cylinders, and maintaining compression with more valve overlap. Therefore you can run a hotter cam and still have good low end torque.

Further, '07 and up cylinder heads flow a bit better than earlier Twin Cam heads and '07 and up stock cams are actually worse than '06 and earlier with less duration and lift.

All of these differences make a cam change in an '07 and up bike quite a bit more dramatic than earlier bikes.