Tim1216

I just put on my roush off road exhaust today, and honestly im not impressed. Ive heard great things about it but it wasnt nearly as loud/deep/aggressive as I was expecting. My truck is an '04 and has 4 cats, would replacing the back two cats with magnaflow high flow cats help make it louder and leave the pre cats alone? or should i replace with this and only have two cats:

http://www.magnaflow.com/02product/s...ne=all&id=5380

Im not sure if those are high flows, ill call them tomorrow. I want my truck to be louder and much more aggressive sounding. Thanks everyone

T Coon

You should just cut your mufflers off

Tim1216

haha i actually didnt have any for a few weeks, just the pipe that came off the cats and still it wasnt loud. thats why im pretty sure it is the cats that queit it down so drastically

T Coon

Yeah I got both of mine cut off and welded a pipe to make dual w/ 4'' tips sounds decent IMO and the price difference was even better ha

06F150CFCT

Yeah the cats are what is keeping your truck quiet. I believe the O2 sensors for the 4-cat trucks are in the first 2. I think you can delete the back 2 cats and replace the front two with the high flow magnaflows and that should solve the quiet issue pretty quickly...haha. I would confirm about the O2 sensors first though. I may be wrong about that. I only have 2 so I never really payed that close of attention to that stuff.

jerrybizzle

From everything I have read removing the back two won't throw codes and will make your truck seem as if you have high flow cats. It also may not seem loud inside as the insulation is pretty good on these trucks.

Tim1216

I was hopin you'd chime in haha. But ok, I know there's 4 sensors total just don't know what they all do. But the thing is that PA needs emissions, so I gotta pass unless I slip some money to a buddy an have him pass it lol. And I'm not sure if they make high flows for the front ones bc they're curved, not straight like the back ones

Tim1216

Yea I would think just deleting them and just having the front two cats would make it a good bit louder. Or gutting them lol. I have emissions though.. I thought about gutting the front cats and replacing the back ones with high flows

06F150CFCT

Yeah Magnaflow makes the curved ones you are talking about...I was looking around on the link you embedded earlier and they have both kinds. You can get universal high flows or the direct fit ones. I feel like the universal would be better for sound but I dont know if they will have the O2 sensor ports.

Tim1216

Yea I'll have to check it out tomorrow. I definately wanna change the cats bc it's just too dang quiet! I also was originally gonna do true duals with high flows with an x pipe and magnapacks bc I love the sound of those trucks, but a guy at a muffler shop told me it would hurt the performance and not run right. Is he correct? I think that would be louder than the roush