What's up everyone? I got a few questions.

I got me an '03 silverado with the 4.8L in it.

Installed a 40 series flowmaster and it just dumps out of the muffler. No turn downs just out the muffler tips, under the bed.

I'm well aware that I didn't gain anypower but I'm not gonna lose anything am I? Cause the thing is an absolute dog when on the highway...

 

I have an 04 rcsb. It has flowmasters on it, and mine was real dawgy until I put some 4.10s in it... I bet you have 3.42 gears...

 

if u can stand listening to straight pipes, do straight pipes

 

Get a CAI , long tubes, and a tune. This will help wake the dog up.

 

I called flowmaster about dumping it and they told me that you have to be at least 6" to 8" back muffler or you will lose low end torque. The motor has to have some back pressure for low end torque. At least that's what they told me.

 

Thats just there answer to try and explain the horrible flow of there mufflers.

What size is it? With a 3" in/out you might be ok. You need an intake, UD pully, e-fan, tune and you will have the 4.8 moving ok.

 

And there you have the truth!

 

eh, i havent experienced any power loss with my flowmaster...im on my second one and this one being a 3" single chamber delta flow....my previous one was a 3" 2-chamber and no problems there...to know for sure, you should have gotten your truck dynoed before and after the swap to find out for sure...but i dont think you'd want to throw money down to find that out

 

My 00' ECSB ran 14.7 with 3" flow pro muffler, K&N drop in, and HPP3.

I got rid of that muffler and got a 3" Flowmaster because I thought it would be better. I lost .6 seconds!!!!!!!! Since I lived close enough to the track I just drove home, cut the muffler off and went back to the track. I ran .7 faster then with no muffler and was getting 2.0 60's. There is a site that shows flow with all the major mufflers for our trucks vs. stock vs. 3" strait pipe.

The 3" 2 chamber didnt flow much more than the stock muffler. The highest flowing was the 3" Magnaflow because the inside of the muffler is 3 1/4". Next best was the strait pipe.

 

Flowbastards.....................