Thoughts on Cat being restrictive......
Road Master
Joined: Mar 2010
Posts: 943
Likes: 41
The cat is exceptionally high flowing. Ceramic car cats use 50% of the space. The very tough and thin corrugated cats can be flattened to way less than 10% of the volume that they are in.
Most can not detect any change in the exhaust when the cats are removed because the flow is virtually the same.
Most can not detect any change in the exhaust when the cats are removed because the flow is virtually the same.
Ultimate HDF Member
Joined: May 2008
Posts: 7,439
Likes: 884
From: 'Noke, VA
Not disputing the fact that the cat is high flowing but there was definitely a detectable difference in the sound of my 10 UC when I gutted the cat with stock mufflers. Not a big difference but quite noticeable none the less. The volume was a slightly louder and the tone was a bit deeper. It sounded pretty damn good. If I hadn't decided to go stage 1, I could have lived with the stock mufflers after the cat removal. The real benefit from gutting the cat was the reduction in temperature on the right side.
Cruiser
Joined: Jul 2008
Posts: 119
Likes: 0
Where do I get my CATS removed?? Will my local HD dealership do this? We don't have a lot of bike mechanics in my neck of the woods...and its not something I would want to tackle! How much $$$ does it usually cost to remove them and install whatever tuners/stage 1, etc...that I would need?
Novice
Joined: May 2011
Posts: 24
Likes: 0
From: Texas
This is a very good point.
Novice
Joined: May 2011
Posts: 24
Likes: 0
From: Texas
I'm right there with ya brutha. Nov. 2012 can't get here soon enough.
Grand HDF Member
Joined: Jun 2007
Posts: 4,599
Likes: 421
From: Lansing mi
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A catalytic Converter is made of metals. It is made to NOT restrict flow but needs to heat up to work. Until it heats up it is almost useless. Once the metals heat up the cat starts functioning coverting the bad emissions into the acceptable ones exiting your exhaust. All that being said, now you have a mass of heated metal and not just free flowing gases that tends to stay hot longer and tends to also be more noticable. taking out that added sound barrier will also help with a bit more throaty sound. There won't be huge gains, but there will be some. Personally, I would do this more for the throaty sound than just the small HP and Torque gains I've seen claimed.
Road Warrior
Joined: Aug 2009
Posts: 1,889
Likes: 104
From: Mississippi
A catalytic Converter is made of metals. It is made to NOT restrict flow but needs to heat up to work. Until it heats up it is almost useless. Once the metals heat up the cat starts functioning coverting the bad emissions into the acceptable ones exiting your exhaust. All that being said, now you have a mass of heated metal and not just free flowing gases that tends to stay hot longer and tends to also be more noticable. taking out that added sound barrier will also help with a bit more throaty sound. There won't be huge gains, but there will be some. Personally, I would do this more for the throaty sound than just the small HP and Torque gains I've seen claimed.