So the flowmaster 40 series sounds better but u lose low end HP...anyone have any expirence with the 50 series? The tech I talked with said the 50 is a little less loud but wouldnt lose any low end HP. I tried a search but couldn't find an exact match to my question. The shop is running a $299 total install on the setup, im thinking about putting them on.

 

I have a 50 series... my truck is completely stock except the catback... so i dont notice any performance form the 50 series... as for sound, it is a LITTLE bit quieter than the 40 series, but has a lot less resonance, and has a deeper sound than the 40 series. loud on a cold start, but if its been running for a while, it has a very quiet idle. It is still plenty loud when you get on it a little. Like I said can't tell you much about the performance aspect of it, i dont think a catback alone will do a whole lot on these trucks. If you got any other questions just ask

 

I had my stock muffler replaced with the Flowmaster 50 series muffler. Like rowdyt said, at idle it is pretty quiet, but plenty loud when you get on it. I myself can not tell of any performance loss since I had it installed nearly a year ago.

I'm happy with it. I was not looking for something extremely loud.

 

I had the 40 series - it had much drone in the cab - so I changed it out for 50....much better - I did not notice and difference in the performance between the 2.

 

Im not looking for loudness either, I'd do a SI/DO...its the HP I dont want to lose. I like the deeper, quiter sound from what rowdyt said also. I guess Magnaflow is best for the F150 as far as performance? But $299...Im leaning towards the 50 series. Thanks for the replies, they're helping the leaning a bit easier.

 

Well I just made 263HP with a Flowmaster Super 40 SIDO and JLT CAI with a very conservative timing and fuel curve. Since I have added 2 degrees timing and leaned out the fuel a little bit and the truck feels real strong. I would go for the sound you want and not worry about a few ft/lbs of TQ. It doesn't matter all that much!

 

the 50 is worthless. people buy it because they want a quieter muffler than the 40 . . . so why not buy a magnaflow/dynomax (stainless) over a blowmaster that does nothing positive for your power?