well, I'm still not sure what to do. When it comes to magnaflows, so many say they like them but then other people say they're not loud enough. It could be the difference between models of the magnaflows, and people are just too ignorant to know that and write it in their posts, like.... 'I got THE magnaflow system and it's too quiet,' like they actually think magnaflow only makes one system. I think the sound clips of them are nice, just can't tell much about volume. I'd probably get the imco if I didn't think it would keep getting louder to a bad point.

 

Higdogg, I'm looking into an IMCO catback system with mandrel bent pipes for my truck. Since I love the sound quality of the Extreme muffler I have on there now, I am looking at a catback system with their "Pro" Series muffler, which is the next step down in volume. It's two chambers like a Flowmaster 40 Series but the innards are a lot more open. I'm hoping it will retain the tone of the 1-chamber but be a bit quieter. From what I've seen on here it is about the same volume as a 40 Series which is fine with me. I understand it's quiet at idle and cruise but very loud when you hit the go-pedal. The system is aluminized (you and I don't need stainless!) The SI/DO system with the muffler and two mandrel bent tailpipes was quoted to me by my local shop at $175 plus shipping. That's one hell of a deal for mandrel bent pipes. I figure with install and some tips it will end up around 250-300 bucks, which is awesome. Exhaust shops around here charge $350 for crush bent SI/DO systems with tips.

 

I don't know anything much about that, when are you looking into doing that? I read on here a while back that the imco 2 chambers are about like flows or quieter. Someone had recommended to not get one. So are you saying that you would have kept the flow 40, or even put it back on now, if it had not caused a noticeable power loss? I'm probably not going to get mandrel bent anything, it was always too expensive. I'm buying all my components and having it put on somewhere, other than the pipe. I'm getting stainless tips, I've had 2 sets of chrome now on my other truck and they start rusting inside of a year whether you polish/wax them or not. Let me know what you find out from reliable sources about the mufflers.

 

Higdogg, I talked to a few people at IMCO and they tell me the Pro Series 2 chamber is about the same volume as a Flowmaster 40 Series. They tell me it is quieter at cruise and louder when you get on it, which sounds good to me. I would not put the Flowmaster back on my truck because it was not a smooth sounding muffler. The IMCO is deeper and smoother sounding to me. The people at IMCO told me the Pro Series sounds the same as the Extreme 1 chamber but is not as loud and provides a little more backpressure for the engine, which is probably a good thing with our engines. As far as mandrel bent, I'm convinced it's the way to go. I know a couple gentlemen around here with some serious performance vehicles and when they switched from a shop crush bent job to an engineered mandrel bent system they gained in power and gas mileage. The angles used in an engineered system are much better for exhaust flow than whatever the local shop says "looks" like the best angle. And furthermore, since aluminized piping is all we need, IMCO's aluminized mandrel bent tailpipes fit the bill. I was quoted by my local retailer (who is ridiculously overpriced but the only IMCO dealer within 100 miles) $49.99 for each tailpipe for the SI/DO system. The muffler for the system can be had for $39.99 on performance-curve.com. That's a lot better than 450+ dollars for a Magnaflow system with the unnecessary stainless pipes. I'm still trying to decide whether to go with SI/DO or SI/SO. There is not a SI/SO available but if you use a SI/SO muffler and use the right side mandrel bent tailpipe it will work perfectly.

 

Well, I guess I'd have to see about that. I don't really want the muffler to be quieter at any point in time, I just don't want a loud drone, and I don't want the overall volume too loud like you described the extreme series. Other than that, I'd like the volume and sound level to stay consistent throughout. Just like the magnaflow, I don't want one to just sound good when I get on it, I don't get on it a lot. I want a good tone at idle and takeoff. Then a noticeable rumble driving down the road, but not something that causes you to think about the exhaust while you're riding, not something that will be so noticeable that it's all you think about in the cab. Guess that's what you mean about the extreme series.

 

Yeah, the Extreme causes a loud drone. On the freeway in the morning it really irritates me as I'm still groggy. It's annoying talking on the phone too because you can't hear very well. The Pro Series seems to be the best compromise available. It also flows better than a Flowmaster. Look at the dyno graphs on IMCO's website. There's a reason Flowmaster doesn't post dyno results.

 

I agree that flowmaster seems a bit shady about some things and their web site really sucked until a few months ago. Even now it's not much more informative on the mufflers and the performance enhancements if there are any. I'm interested in the imco for sure, just not sure at this point if the 2 chamber will be loud enough for me. If it's loud enough for you then I know it will be for me because you're still younger than me. That's what holds me back on the extreme because if you like it louder than me possibly, and you can't handle it then I know I can't. Thing is, I listened to my stock muffler and I could see where some drone might come into play on an aftermarket around the 35-50 mph range, but after that the truck shifts and most noise is gone. I have 3.52 gears if that makes a difference between yours and mine. Plus you said you took the silencer off the intake, which might make more noise for you , I don't know, I'm not experienced with that. I don't see how it could make exhaust louder unless it blows out harder or something from increased intake. Did the guys you talked to at imco have any ideas about why yours is so loud, or is it just the muffler for real?

 

Higdogg, the people at IMCO said the muffler is designed for the Fords with 4 cats 1997-2003 to give them a sound level equal to the chebbies and dodges with Flows of the time. We only have 2 cats and they flow better than the older models so that is why it is much louder on this truck. The exhaust definitely got louder after the intake mod, and that is simply because more air in=more air out.
I have 3.55s as well (they suck with my new wheels/tires , 4.56s by February ). I just need to figure out whether to go SI/SO or SI/DO. I don't want to lose backpressure like I've been doing since I started changing exhaust on this thing. SI/SO would be 2.5" mandrel bent, SI/DO would be 2.5 in/2.25 out mandrel bent. I'll let you know when I figure it out. It seems finding the right muffler for this truck takes a lot of work!

 

See I don't get that at bad drone at all. I have the 5.4 and mine for the most part is fairly quiet on the freeway.

 

05scfx4,

I have 5.4, so yours is quiet cruising w/ the imco extreme? how long have you had it?

 

Mine is not obnoxious like they some are saying. I mean it sounds good at idle, and sounds AWESOME at WOT....but cruising on the freeway between 60-85 it is not bad AT ALL. I have had it for about 700 miles now.

 

fourpointsix, how long have you had your imco and how many miles are on it now? Seems like there is something relative to the 4.6 or the air intake mod that you did that is causing yours to be so loud. I'd love to hear it, is there any way you can do sound clips?

 

wonder what IMCO's sound like with no cats....?

 

I have the Pro series SI/DO on my '05 F250 SD w/5.4 and it sounds great... Pretty loud at startup, burbly idle, wicked sounding when getting on the throttle and mellow when cruising. It sounds deeper and richer than the 40 series to me... the Flows seem a bit hollower sounding than the IMCOs. I imagine the Extreme series would be SUPER loud on my truck.

 

I'm not sure abotu you guys, but I was warned when I bought the IMCO extreme, both by the person from IMCO and also from the exhaust shop. They said "are you sure you want it loud? Because if you dont want it loud I wouldn't go with the extreme". but I think the exhaust noise is perfect. Like others have said, not too loud on the highway that its annoying, but loud enough at WOT and even when idling that the truck has a reasonably presence.