Exhaust pickle
 

I got a GMC Z71 with the 5.3 and I'm in a bit of a pickle. I have dual Glasspacks and they're way too loud. I want to change out the Glasspacks for something a little quieter but, the idiots before me gutted the cats and ran the pipes retarded like. One pipe is going straight out and the other is cocked at a 45 degree angle away from the other. I'm wanting to know of any muffler that'll give me a little more power and alot quieter tone inside and out.

3 stage flowmasters!

Ditto Flomaster.

I'm thinking the 70 series or 50 series with tips exiting behind the rear wheels.

If you fix the cats dont run the 50 or 70 series flows..run the 40's, they or not loud at all with tail pipes and cats intact..I ran cat delete and headers with super 40's dumped before the axle on my last Z and sounded great...I still get people telling me about the sound of that truck and dont even own it anymore...

I may fix the cats, I may not. Depends on how much longer I will keep the truck. I know I will soon change the exhaust. Its driving me nuts. I may also get it repainted blue or go back silver and get a blue boat since blue and silver is bad asthma.

Flowmaster is what I have

What series? I want something not loud to wake the neighbors when I start my truck to go fishing or hunting and also for long road trips cuz I can barely hear my passenger(s) over the drone.

I had glasspacks on my 97 Chevy with the 5.7 350. Had straight true dual exhaust with some 3 1/2" x 24" long tips coming out the back corners, that truck was LOUD! It was definitely the winner of our "who has the loudest pipes" contest between friends. On my current truck (07 Silverado Z71 w/ the 5.3) I just have flowmasters but I'm not sure of the series (was on the truck when I bought it). It has a good deep tone but isn't loud.

I don't understand the whole making your truck louder thing. I make some really long trips and listening to that racket gets old!

To be honest with u I really don't know. I've had them for about 5 years now. But they aren't real loud

I have a 05 Dodge Hemi with with the 50 series. They turn down right out of the muffler. It has a good throaty sound but not rattle your teeth. I can't stand the loud redneck straight exhaust sound.

THANK YOU! All my friends have straights on their trucks and they all sound like crap. I like to not wake up the whole hood on start up and take off. Its a close race between the 40,50 and 70 series right now.

I had the exhaust done several times on my old truck. 2001 f150 5.4.
50 series flowmaster. No
40 series flowmaster close but no. Not throaty enough
True dual s using thrush mufflers. That where it's at. Not to loud but deep. Glasspacks are. Retardidly loud.

Magnaflow is also a good muffler that is not very lound. Nice deep tone without the noise inside the cab.

How much of a power increase would I be looking at with a magnaflow roughly if any?

Likely none.

A simple muffler swap give your very little to no hp increase. You will see the most hp increase with mandrel bent exhaust system. The smoother and least amount of bends in the exhaust pipe has more to do with hp increase. I managed a meineke car care for 3 years and this was a huge debate. Most people think the bigger the pipe and least about of restriction equals more hp. That is far away from the truth on a stock or lightly modded engine. Only time that is true is on high hp engines that need the extra exhaust flow to allow the engine to be efficient and make the hp. In your case with no cats and glass packs you are actully looseing low end torque and hp. Stock engines need the backpressure that comes from cats and a muffler to run at peak hp and tourque.

Just cut your pipes at your heads....then you could wake all of St. Amant up instead of just your neighbors...

You hit it on the head, especially with the last statement. You will lose hp and fuel economy if it isn't set up right.