Anyone use flowmasters on these trucks?? I've heard they sound really good from some people and really bad from others, so whats the truth??

 

Bass, I have flow thru mufflers and I have no clue of what brand, work fine, sounds like a harley when stomp on it @ 2100 RPM...the shop I went to a shop that specialized in custom exhaust. If your interested I could find out for you?

 

Right now I have a glasspack, I want something with a more mellow deeper tone. 40 Series american thunders sound great on gassers, and I'm sure there would only be a slight difference in the tone with a diesel.

 

I have a Flowmaster 40 muffler in the stock exhaust system on my rig. Has good flow and a nice tone when you get on it. Not insanely loud but has a nice roar especially when your pulling a load. Works great and has metal fins inside the muffler so no worries about plugging it. Would sound alot better with a larger exhaust though...

-Dave

 

Flowmaster doesn't recommend their mufflers for Diesel engines. The high pulse of the diesel's exhaust tend to blow holes in them. Doesn't say much for how they handle flow to me.

 

Really? I never saw anything that said not to put it on a diesel...In fact, if you look online, they have their 50's series listed as diesel recommended. I think I saw that on Active Auto Parts website. But the 50-40 series have the same construction, why would they be any different?

 

We tried to buy one (probably a 40) from a local performance warehouse a couple years ago to put on a bus and the guy wouldn't even sell it to us. He said they weren't for diesels. We found out what he ment a few weeks ago. We had a different bus come in with a pair of 3 inch Flowmasters on it. One had the whole side blown out of it. This was on a Detroit diesel, so a lot bigger and lots more air due to the blower, but still. I'd never put a baffled muffler on a diesel.

Yes, I'm calling the FM baffled. Sorry, I don't like K&N air filters either.

 

I just bought the flowmaster because I couldn't afford a complete exhaust system at the time and it would improve flow. I can say that it improved the flow part but not very much sound unless I was really on it...

 

I have dual 40 seris flowmasters with 2.25 inch inlet and outlet with 3 inch tailpipes.on my 6.9 IDI. Had them on there for a couple of years now. Love'em!! Sound is awesome. No holes or porblems of any kind. Run'em and Run'em hard!!!!!!

 

I have the same setup expt 2.5 in and out into two 4in stacks in the bed.
sounds awsome. no problems at all.
Im going to change to dual 3in w/ FM outlaw race mufflers, for better flow.

 

Chambered mufflers work well on the N/A motors, but they are a restriction on the turbo motors. Flowmaster does have straight through mufflers for turbodiesel applications now.

Welcome to FTE paw73!!

 

Yeah, but they're just glorified glasspacks, which other companies have cheaper.

I personally fail to see how a Flowmaster could get the case blown open. Besides the fact that they're made of very heavy gauge steel, the cases are fully welded. Those things are pretty stout.

Only reason I could see was if the exhaust was too small for the engine in question, and there was an excess of pressure in the muffler...but with a 40 series that seems unlikely...I dunno.

If I can pick up a truck with an IDI like I'm wanting to, I'm already planning out a nice 3.5" or 4" exhaust system with a big 40 series on it

 

yah, i dont see how they would blow out. From what I have seen, and I've worked with a bunch of 40's on gassers and to me they are way better built then most other mufflers. All the welds are clean and metal is of high quality, so unless your putting them on a big rig or someting then I dont see how theyd blow holes in em.

 

not to mention a 302 can easily outflow a 7.3L..a 302 at 5000rpm flows 437cfm. A 444 at 3000 flows 385cfm. Those rpm figures are conservative. Most people dont push their engines past that. Lots of people run at least dual 2.5", if not dual 3" on the 7.3L. Most people run 2.5" on a 302, that is passing more cfm through generally smaller pipes = higher pressure. So if the Flows last on a gasser engine they should easily last on an IDI.

 

Ok I was at the salvage yard looking for a rear seat and I literally tripped over what i thought was a POS muffler. It was actually a flowmaster 40 series. 20 Bucks and it was mine, welded it on and it sounds freakin BAD A. Its got a deep tone, somewhat like a gasser with flows, but of course it is way louder. My truck jumps off a light instead of slowly gaining speed, I dont;t know if its the muffler or the colder weather but the muffler is helping