If you MUST use glasspacks, get some preforated ones (little holes). The louvered GPs are absolute crap. The louvers stick into the exhaust stream, cutting down on flow, and thus any gains you wanted from the new exhaust system. Effective pipe diamater is usually cut down one pipe size using these POS's. Turning them backwards does nothing except make them louder, they do not flow any better, and in some cases, worse.

I would not take a pair of louvered GPs if someone PAID me to take them.

 

I think im going to turn it around today, Redhots were the cheapest I could get at the time, and i dont have the money to spend on exhaust right now. Once I get some cash saved up Im going to either get Stacks, or 3 inch true duals with super 40 mufflers.

 

The new Summit catalog,exhaust section..Dynomax has a new muffler that looks like a combination of glasspacks and X-pipe, looks interesting.

 

Allied glass packs are the best. They are actually classified as resonators but the flow as well as magnaflow & flow master- when you compare size to size. Most any muffler shop will have them and range insizes from 10" to 38" IIRR. Nice deep rumble, nothing obnoxious and very well built...cost runs on avg $20-$40 each depending on the size.

 

You might as well not get new exhaust if you are going with Flowmasters, dual 2.5" with Cherry Bomb turbo mufflers will flow pretty much as well and sound better, The 3" pipe alone would be a waste unless you are running a built big block. Run a dual Magnaflow system and the flow will be great, sound will be awesome etc. Also, speaking of Dynomax, I just found out Midas is going to drop Ravin and go with the Dynomax line, the guy I talked to in town laughed and said if he had his way he wouldn't touch it. But they are keeping the Blue Bottle line.

 

beach are you running these alied glass packs ?? i have 2 1/2 summit brand 12 inch glass packs but their just too dam loud and i hate the decell cakle .. but i do love the idel ..i need to do some thing cuz i know the new cost of mufflers are cheaper than a ticket .. by design i dont think i can put a standard muffler in without redoing my ehhaust as it was done with the glass packs in mind ... in the summit catalog i saw some thrush that are 45 inchs long .. im looking for some feed back on these wil it mellow it out but not to the point of making a sissy out of it ???? im likeing the thumbs up i get .. but i do need to quite it down just a tad ... thanks all .. russ

 

351 M Im running a Diesel so 3 inch wouldnt be a waste, i dont have a gasser, wouldnt own a ford gasser neways no offense, been a chevy racing fan all my life, grew up around chevy engines, but when it comes to a diesel i dont want to put a 350 with glowplugs into my truck so im a ford fan all the way, unless you get into the 70's model fords i like those body styles but id drop a 454 into one if I had one.

 

On a 6.9, single 3" wouldn't but I was under the impression that you meant dual 3", that would be pointless. Even with a diesel you still wouldn't be making use of that size pipe.

 

If I go single id get 3 1/2 to 4, dual i might go 2 1/2 or 3 or i might just run 4 inch stacks and be done with it!

 

I had a set of the purple hornies that bolt right up to the header collector. They sounded great, except when you have a cop behind you who's probably wondering why it's taking you 6 miles to get up to 40 mph because you are afraid to open it up and get pulled over for illegal exhaust. Eventually they get aggraved and just pass you.

 

LOL, weird, they usually pull me over in my cavalier. Probly has somthing to do with the fact that A: it takes about 6 miles to get to the speed limit and B: they can't see a muffler, only a 4"x24" Chrome tip. That and pretty much the only time there is one behind me is when I'm out @ 3 AM on the weekends(Not drunk but they check because I'm going so slow while they are behind me)

 

has any one changed over to longer packs with good results ?? i have 2 1/2 summit 12 inch packs on their now and their just tooo loud ... ive seen i think thrush ?? at up to 45 inch's.. i hate the idea of going a turbo muffler route cause my system was made with packs in mind and i dont think the cases will fit with out some mods .. and wifey still kinda cranky with the cost over runs on this sweet , unbeliveable cheap, have to have or ill die , will hardly take any time or money ,the last thing ill ever want , easy project truck lol .....

also does any one know how to change the personal password for this site ??? it doesnt no longer match my others and my memory isnt what it used to be lol hope everyone's haveing a great day .... russ

 

The longer the GP, the quieter it will sound. Although I think a 45" GP would not be any louder than stock. I didnt know they made them that long.

 

45" will be fairly quiet but will have a decent tone. I did a fairly extensive tuneup on an '80 F-150 with a windsor that had dual 2" and 45" packs, sounded not too bad, couldn't hear it inside but sounded nice out back.

 

I have dual 2 1/2" in & out 45" Thrush GP's behind my 390, Jones cam,Sanderson headers...They sound.....GOOD. I did not hook up my cd player for along time bacause the motor was sweet sounding enough.