How restrictive is the CAT really

Zug · 03-27-2011, 10:04 PM

I always wondered how much the CAT really effects the performance of the bike.

As the bank account is very low at the moment and I don't have the funds to get a full system a friend of mine suggested that we gut the CAT as this will cost nothing. He has a mig welder (and knows how to use it) so we cut it off just before the CAT and I was a little surprised to find that it is just about completely filled. That honey comb you see is filled with something (I think it is some sort of carbon) that turns into a white powder when drilled.

Where the headers go four into two just before the box you find this honey comb. From where the pipes diameter gets bigger to about 1/2 an inch into the box so it is about 3 - 3 1/2 inches long. The box itself has a few chambers in it but it is fairly open and you can see that it will flow much better once it is all out.

This is what it looks like when it is all out. sorry the pictures are not that great, phone camera.

bobafeets · 03-27-2011, 11:56 PM

Nice. Notice any sound gains? Deeper i assume. Couldn't get a bit o pipe and make a y joint for it? it may not be the best quality but I would just assume(on nothing more then opinion) that it would be slightly better and look nicer. but if your trying to keep the exhaust stock then your on the right track!

**JACOX** · 03-28-2011, 12:21 AM

Quote:

Originally Posted by Zug

I always wondered how much the CAT really effects the performance of the bike.

As the bank account is very low at the moment and I don't have the funds to get a full system a friend of mine suggested that we gut the CAT as this will cost nothing. He has a mig welder (and knows how to use it) so we cut it off just before the CAT and I was a little surprised to find that it is just about completely filled. That honey comb you see is filled with something (I think it is some sort of carbon) that turns into a white powder when drilled.

Where the headers go four into two just before the box you find this honey comb. From where the pipes diameter gets bigger to about 1/2 an inch into the box so it is about 3 - 3 1/2 inches long. The box itself has a few chambers in it but it is fairly open and you can see that it will flow much better once it is all out.

This is what it looks like when it is all out. sorry the pictures are not that great, phone camera.

Get a Dremel or drill wire-brush and clean out that base material to get a smoother flow. The save your money and check out Austin Racing for their AR-CS Y-pipe; you can even use the stock can, but their stubby's would be even better . Forget the bucks of a full header system. IMHO

JGraves · 03-28-2011, 12:38 AM

I put a full Akrapovic titanium exhaust system on my Motorsport bike with a Power Commander and the power gains are simply amazing. If you had to replace your stock exhaust it would cost almost the same. Sure it is not cheap, but save your money and it will be worth it in the long run over taking short cuts that will cost you more in the long run.

Zug · 03-28-2011, 01:25 AM

Quote:

Originally Posted by bobafeets

Nice. Notice any sound gains? Deeper i assume. Couldn't get a bit o pipe and make a y joint for it? it may not be the best quality but I would just assume(on nothing more then opinion) that it would be slightly better and look nicer. but if your trying to keep the exhaust stock then your on the right track!

I have not put it on the bike yet. Will be welding it back together tomorrow and should have it back on the bike by the weekend. I have a before sound clip and will do an after one and post it.

My friend who is doing this for me has drag raced (cars) for over 17 years, had his own shop for many years and even taught mechanics for a few years. He really knows what he is doing, so we are not taking any short cuts that will cost me later, I have full trust in his work. He has helped me with projects on just about every bike and car that I have had and they have all worked out very well. The Y joint was an option and yes it would look better but it is not that easy to do yourself and I just wanted to try something else.

I REALLY do not want this to turn into another removing just the CAT from the system... thread. Thank you for you comments, it is not that they are not appreciated. I know about the full systems, the AR-CS and the DIY link pipe. I know most people would say to go for the full system or AR-CS but when my friend suggested this, I thought I would try it and was just really surprised at what I found in the pipe and thought I would share. It really goes to show that the stock system is very restrictive.

When I have the money I will go the full system and PCV but until then....

Mrgrn · 03-28-2011, 01:37 AM

looks good and you accomplished the same as a new expensive Y pipe, splendid DIY work

also, post a pic of your TL it will motivate me to find and buy one

Zug · 03-28-2011, 01:47 AM

Quote:

Originally Posted by Mrgrn

looks good and you accomplished the same as a new expensive Y pipe, splendid DIY work

also, post a pic of your TL it will motivate me to find and buy one

Thanks.

I am selling my TL!

http://vancouver.en.craigslist.ca/va...285815227.html