High Flow Cats

[slysnake]

I have my side sills off now for a repaint because of rock chips and I was thinking this might be a good time to put on some high flow cats. My questions are: 1. are they very expensive? 2. Is it a DIY project or is it something that needs to be done in a shop? I have an '05, as you can see from my avatar, with stock exaust.

edit. Oh, another question. how much will this change the sound?

 

[slysnake]

OK, I see parts rack has them for 569. so that answers part of my question.

 

[mrnycguy]

First things first, best color ever although I’m quite biased (copper coupe “money penny”). Personally I dig the design of the roe hf cats or any with a flex pipe, it’s a diy as long as nothing is welded on your current setup and you match the exit of the cat pipe size to your mufflers (not needing a reducer welded in). The hard part is getting the sill off and alignment when putting it back other then that have at and post pics and vids when done.

 

[slysnake]

First things first, best color ever

Agreed! In fact I think I posted a while back a "scientific" study that proved the copperhead combined all the positive aspects of red and yellow cars without their negative down sides. Making it, indeed, the fastest and best color.

Thanks for your info

 

[SilveRT8]

I have the Roe's with reducers to fit the stock mufflers.
Sound will increase at least 50% on start-up and at WOT, but will stay quiet when just cruising, no drone. To me, it has the same effect on sound as changing to a catback muffler system, but this way it also reduces the restriction caused by the 4 OEM cats. Speak to JonB, as he knows more about this and has many options to consider.

 

[JonB]

To answer your question, the more you flow, the more you blow: CFM and Db.

We can add the (restrictive, hotter) flex pipe and up the price. Look inside a flex pipe.
After consultation with Belangers and Random, we concur that as long as the elbow-bracket is not used (not needed) why add to the cost, the weight, heat, and the restriction?

We can guarantee and publish flow rates for our cats.....but they drop if we add flex. Your Choice. We have OE sized (no reducers needed) or 3" (reducers optional) in both cermaic and SHF Metal Honeycomb. The ceramics have a nice, deep, mellow muscle-car tone. The SHF Metals are noticably louder still.

ps we had a well-publicized warrantee issue (but only on 5-6 modded cars) when we USED to have brackets. My Bad. Shoulda listened to Lou.