Anyone have any experience with..

[SteveSierra]

Anyone out there use these mufflers in a true dual set up, hopefully on a 6.0?  

I'm looking for mufflers that are louder than Gibson's(had that on my Tahoe and Z71) but also flow better as well.

I don't mind some resonance in the cab, but not too much.

I want some deeper tone to my exhaust, but don't know if I want dual 40 series kind of tone.

Thanks!

 

Steve

[leathal02]

i have the 50 series on the 5.3 L

[DigUout]

Check with Chevy4X4Trucks.  I know he has a smaller engine than the 6.0, but he has the American Thunder Flowmaster set up.  Sounds like he really likes his -

[Larry]

I bought a 98’ Z71 in April of 98’ then the wife and I drove 1500 miles back to CO from MI to get married that following August.  Once we got home to CO, I couldn’t wait to bend up some pipe at my dads shop and mig weld on a dual inlet dual outlet Flowmaster Deltaflow 50 on the Z71. I don’t notice a single gain in horsepower or mileage but I did notice a loud annoying noise coming from the passengers seat a week later by the time we hit Chicago on I-80 during our ride back to MI.  After a burning sensation in the seat of my pants and noticeable teeth marks, it was determined the noise and sensation I was experiancing was the wife chewing a hole in my butt because of the constant resonance of the flowmaster muffler rattling her precious ears.  Needless to say, before we took our annual trip across country the next summer I had to remove the Flowmaster and try something else. Since I already canned the stock muffler I tried a Dynomax muffler instead. The truck didn’t sound nearly as mean but the cab resonance was much more tolerable for the copilot.  I still have the Delta 50 tucked away in my garage and I have been thinking about sneaking it on my new 8.1L HD…hehe.  She doesn’t need to ride in that truck anyway.  Especially since we no longer have to make 24hr road trips across country.

[SteveSierra]

I think Chevy4x4Trucks has a 40 series on his.  I was going to go with 40 series, but I'm beginning to think dual 40's might be too much.  I dunno.  I found a shop that bends 3 inch pipe(everyone else was saying they only bent up to 2.5 inch), so I'm going to them tomorrow morning to see what they can do.

Kinda funny as this place is the shop that did exhaust work on my very first car 17 years ago(79 Monte Carlo, 305 with a Rochester quadrajet, oooooooo!!!!lol)

Does anyone think it would be better to do 2.75 inch pipes out the back instead of 3 inch for backpressure purposes? Or should I just have them install an h pipe?

 

Larry,

I hear ya on the wife complaining about noise.  Fortunately, I can't get the car seat for our 5 month old girl to work well in the back seat of the truck, so we won't be doing any family trips in the truck.   My soon to be 4 yo son is impervious to noise, so I don't think it'll bother him too much ;)  He likes riding in the truck.  Actually going to take him on the beach this summer to go surf fishing. He oughta love riding on the sand.  Gotta teach em when their young to fish!

[DaveRuane]

I have the ne 50-series Flowmaster #530504 (dual 3" inlet/dual2.5" outlets) on my 2001 2500HD CrewCab 496c.i. w/ allison.

 

While this truck has factory dual cats, I chose this single muffler application due to the need for some exhaust crossover. I have 2.5" pipes exiting behind both rear tires.

Here are my observations:

 

Much quieter than expected - I like the sound, but it is mellow except on full throttle. My wife didn't notice at first (tis is a good thing). On full throttle there is an excellent flowmaster grumble, and a cackle at the end at times.

 

Performance - At first, I thought I had some decrease in acceleration or throttle response at initial acceleration. Still experimenting and validating, but it may be the new sound throwing me off. On a favorite stretch of highway, it does appear I can achieve a higher mph in a shorter distance. My understanding is that a free-flow exhaust can decrease your performance out of the hole, until some back-pressure is achieved, but should improve your overall performance - a consideration in even looser dual muffler apps.

 

Mileage - well, with the new sound comes a lead foot. I think I will see a gain after the excitement has wained... I am seeing about a 1 mpg decrease at this time (installed about 4-weeks ago) I do expect a better overall MPG in typical driving.

 

Other observations - the HD pickups make a straight out the back tailpipe set-up hang too low (HD has body lift and obtrusive hitch package from factory). The behind the wheel exit isn't as neat-looking, but does allow you to hear it from the driverside window a little better. The next step for me is to add a K&N Aircharger/FIPK intake system to further the free-flow performance.

 

Hope that helps!!!!!!!

[SteveSierra]

Dave -

Thank you very much for that response.  It's kinda ironic cause the shop I was at yesterday mentioned that exact muffler.  I called Flowmaster last night to double check on the 3 inch exit pipes and they said that unless I was pushing 500 + horsepower, I would lose most of my bottom end.  2 1/2 sounds better to me now.  I will never be pushing 500 + hp in this truck! haha!

That is sorta disappointing to hear that it is fairly quiet.  I had a Gibson exhaust on another truck and I had the same impressions, almost non existant at idle and throaty when you get on it.  I don't want another Gibson sounding system. Hmmm, I guess I should have asked them about the 30 series.  That doesn't seem to be as loud as the 40 but is louder than the 50.

Did you have to remove your spare tire for the exits behind the rear tires?  If he used 3 inch tube, he would need to, if he uses 2 1/2 inch, he thinks he might be able to squeeze the left pipe in there and tack a heat sheild on the pipe that runs behind the spare tire.

Thanks!!!

Oh yeah, when I asked the guy at Flowmaster about the 40 series dual mufflers, he said on the 6.0 it is LOUD!  I wonder what makes it so loud on the 6.0???

Steve

[Beaux Duke]

Steve,

Just thought I'd throw this out for your consideration and you may already know about it.  www.edelbrock.com has examples of how their muffler sounds on various trucks.  They let you hear what it sounds like at idle, reving it up, coming at you and going away.  It might not be the sound you're looking for but hey, who knows?

 

If you're interested, just click on "Exhaust Systems" then click on the downloads.

[SteveSierra]

Beaux Duke -

Unfortunately, I'm at work and don't have speakers.

I just called up the shop and had him order 2 50 series delta flow mufflers. 3 inch in/out.  He's going to use an adapter thingamajig on the outs and have 2 1/2 inch pipe exiting behind both rear tires on a 45 degree angle.  I might get 22 inch chrome slash tips, I'm not sure.  Don't know if the chrome tips would look silly or not.

This may be the beginning of my quest for the perfect setup.  I can see it now, by summer I'll have been through 5 different kinds of mufflers. LOL

[1BADHD]

I am planning on putting on a Flowmaster also. I have looked around to see what everybody in town has done and there is 2 set ups I have seen. One is true dual 40 series flows and the dual in dual out 50 series. Now let me tell you what if you want that annoying crackling sound get the dual 40's. Now my buddy got a dual in dual out 50 and they day he got it, it sounded a very mellow. He took it on a trip where he pulled a trailer in 3rd gear. He must have burnt it out or something because now it is perfect. It has the very deep rumble at idle and a nice mellow hollow tone when he cracks it open. So from what I have experienced first hand, I am going with the dual in/out 50 Series Flowmaster.  

[DaveRuane]

Some comments on previous replies -

 

not sure you will be able to fit 22" tips on a behind the rear wheel exit. Also, a 45-degree angle might be difficult as well due to leaf-spring clearance. I was disappointed to see mine exiting with an almost 90-degree angle, but then looked, and noted that a lesser angle might bang on the spring.

 

I used 2.5" pipes and after seeing some of the bends that needed to be made, and how those bends cause smaller pipe diameters, I wish I had used 3" pipes.

 

A dual muffler app will definately be louder - especially with 3" pipes. Make sure they add in an H-Pipe, or crossover to even out exhaust between cylinder banks. I think Flowmaster strongly recommends this to avoid check-engine lights.

 

I have heard a few people mention that the Flowmaster will get louder after "break in". Not sure what the mechanics of a non-mechanical muffler would be regarding "break-in" but I have noted that they do seem louder than the first week! Can anyone explain this phenomenon?

 

Thanks - Dave

[SteveSierra]

Dave -

Maybe them getting louder is due to carbon depositing?  I don't really know, just throwing something out there.

The guy that is doing my exhaust install said that I'd need to remove the spare tire with 3 inch pipes, but with 2 1/2, he seemed to think it might just clear the tire and he'd tack a heat shield on the pipe by the tire.

He called Flowmaster to find out about the 50 series dual in/out muffler and they told him that unless I was producing over 500 hp, 3 inch pipes behind the muffler would rob alot of the bottom end torque.

He didn't think that it would be a problem with the 45 degree exits.  I actually saw a 2500HD about 2 weeks ago that had 45 degree angled pipes on it.  I thought about chasing the guy down and asking him about his exhaust setup, but I didn't want to look like some whacko. LOL

I'll post my impressions of the exhaust setup next Thursday for anyone interested.