Well I am telling you form experience, I have flowmasters on my truck right now. They are good mufflers, but they are not a god sent. Yes the flow-through design of the Magnaflow muffler sounds like it would be alot better than the Flowmaster. As far as it being better than a glasspack,could be, I dont know because I have never had a Magnaflow, I do know the Magnaflow does make a glasspack. You have to understand that the brand doesnt sum up the muffler. I mean if your wanting a muffler for a Lexus, and you want it quiet, but you want as much performance as you can get, well Flowmaster and Magnaflow and a gazzillion other companies offer something for it. But youll pay out the nose. But a Flowmaser 40 series is nothing like a 60 series, performance wise or cost wise. If you want cheap and less restrictive than stock, buy a glasspack, hell buy a Magnaflow glasspack. If you have a little more money to spendgo with a magnaflow, or a borla, even a flowmaster. But coming from someone who has 2 installed right now, dont think that your gonna spend 75 bucks for a muffler, 30 to 50 for install and get like 25hp out of it.

And on the other topic, why would you bother getting exhaust works done guys if you werent goin to have them cut out that ignorant y-pipe? Find a shop, do true duals, buy your own mufflers and take them to the shop your getting it done at, have them throw in some chrome tips for free,WHALA!!! If you cannot find someone to do this for under $280.00 then drive to florida. I know shops that would do it for a cheap as $240.
And that setup is about the most your going to get out of your exhaust for as little money as possible.

 

You are exactly right bro. Flowmaster builds a great muffler, but there not any better than the other good muffler companies and a $19.95 Turbo cal400 Dynaflow from Discount Auto Parts would yeild almost the same benifits for this guy.

 

i've been runnin true dual true straight pipes(just pipe and gutted cats,nothin else) for about a year y-ed out with no muffler and no cats or a flowmaster off and on for a year before that and my truck runs just as good as it did the day i bought it.you'll never blow an engine because of your exhaust.you can crack your heads if you run open manifolds or somethin like that and you can burn valves if its too restrictive or wear out valve springs if there's not enough backpressure.as long as you run the right size pipe straight pipes will not hurt you much if any more than running the stock exhaust.like anything its a trade off.if you do anything to increase horsepower you take away a little engine life usually.

 

Interesting that you say that, the exhaust shop I use, the one I have used since I was 16, told me the they will no longer do straight pipes/no muffler on the 4.6 and named 2 Dodge engines as well. They had done 6 F150's in the past year or so and all but one has blown the engine. Two of the trucks they were forced to aid in the replacement of the engine because the dealer after checking everything else had conlcluded that the lack of restriction had caused the ECM to run the mixture too lean, altering several other critical componets and thus starting an effect that eventually led to damage to the valves and a complete top end rebuild. The tech did say that if something had been done to inrease the airflow coming in, then the exhaust wouldnt have caused such damage. But as you said, would still reduce the life expextancy of the motor. It is hard to say what will have such effects anymore. The Ecm has its hands in every part of your system, and throwing something minor off can have a great effect on timing,fuel mixture, camshaft, etc.

 

when one is runnin that lean its gonna get a mil.maybe when they got their exhaust they justragged the hell out of it and blew it.like i said my truck runs like a top,so doesmy friend's 4.6 and i don't know about his but my plugs look fine every time i pull em.choppin just the muffler off does not take thatmuch backpressure off of em.and valve train problems is not a blown engine.and like i said when you do it the right way you won't have any problems.what about tons of mustang drivers that run straight pipes and have no problems? you ever stop to think maybe that exhaust shop screwed em up?i'm not sayin go throw headers on somethin and straight pipes with the stock filter or even without resettin the computer,cause that is stupid and pointless.i'm just sayin that i've done it,my friend has done it andi run the total helloutof my truck.if mine holds up to complete straight pipes then as long as you do it right you'll be fine.and not putting an intake system on a truck with exhaust would make it run rich,not lean.i think they screwed up somethin in theo2 sensors or somethin cause that just doesn't makeany sense to me.

 

What you are saying here does not make any sense. They are claiming that the truck was running too lean, then they say that adding more air would have helped. Last time I checked, adding air would lean it even further.

The ECM is not going to make the truck run lean. The ECM will try to richen the mixture if it detects a lean condition. The only way to go too lean is to make enough modifications that the fuel rate needed exceeds what the stock injectors can supply, and simply opening the exhaust isn't going to do that. Now, if you did something stupid like pull the cats and bypasses the 02 sensor, then yes you can lean the engine enough to cause damage.

 

witey - dude, p-u-n-c-t-u-a-t-i-o-n

 

Here's a link from ChiDriver's photo gallery on this site, he has a pic of the inside of his y-pipe, the internal opening is only 1.6 inches. Show your exhaust installer

https://www.f150online.com/galleries...3029&anum=2504

 

what are you talkin bout puncuation?iknow mine wasn't perfect but i threw in some periods and other crap.atleast i know what i'm talkin about that's what matters.thanks you jeeps its nice to see somebody who uses their own brain and doesn't just go on what an exhaust shop(of all people to listen to) says.and about the y pipe,it ain't no 2 5/8's that is stupid to say it goes that much bigger cause the exhaust is 2.5 the whole way,and you can tell its smaller just by lookin at the outside of the pipe without even lookin inside.it does get very small inside it.i cut mine apart when i dualed it out just to see.i don't have an exact measurement but i can get one if you want one and if i still have that pipe.

 

Thx man. I will. I think that guy is sort of, hmmm, I don't know the word.His fam has a good background in automotives but I think his info of what he gets from the other shop members teaches him bull****. He knows his cars but apparently doesn't knowe the tritons or the fords like he says he does....