So I've been reading a lot of forums and noticed no one really mentions anything about flow masters on the GXP LS4. I was thinking about getting a res delete and 2.5in pipes to super 40's with 3.5in quad tips. Eventually getting high flow DP. YouTube videos aren't any help to me. I wanna know who actually been around this type of setup and their opinions.

 

I have not had them but from what I have read, the flowmasters will drone and are fairly restrictive.

 

40 series w/ res delete.

www.youtube.com/watch?v=CkA6daaubnk&list=UU7esxEPM8Y2cYJnLgtB9T3Q&index=42&feature=plcp

I got a lot of complements on the sound. They do drone, however. I will be putting up a new QTP electric cut out with wireless controller in the classifieds tonight when I get home. That is a good option too.

 

That sounds great. How bad is the drone though? What RPM is it? I used to have a 94 suburban with single 3in super 40 and it wasn't that bad. That thing was acoustic. Plus I have a loud stereo to help.

 

I don't get a lot of drone.

 

i'll get one of mine when i head out to lunch. i have stock back to the y-pipe then i replaced the y with a single in dual out 1 chamber flowmaster(knock off).


the single muffler gives it a little different sound, kind of like an fbody.
i dont get much drone at all, but with the resonator still in place thats probably helping that.

texasgxp08 that sounds really good. what tips are those? i want to redo mine i'm just using single 3inch tips i had laying around from my old mustang...

 

I'm wondering if making the y pipe stainless will help? I read that changing the material density raises the rpm it resonates at. So it's less noticable.

 

Sounds awesome! I too would like to know what tips you have on the car. Are they 3.5 inch?

 

This.

Sound quality is subjective, and I think they sound pretty good, but I've heard from seemingly dozens of sources that they're all very restrictive, with some (80 series etc.) being even more restrictive than stock.

For my money, it's either Spintechs or Magnaflows.

 

I went with a pair of 2.5" Thrush welded mufflers (basically a Flowmaster 40 series I believe). Stock cat/resonator in place. Just had these welded up in place of the rotting stock ones and had the stock tips pushed out about an inch.

I was concerned it might be a little loud, but it is almost too quiet for me. Realistically that is better I suppose in my case. Sounds nice at idle. Helicopter sound is faint w/ DOD. I'll likely get a cat-less downpipe down the road if I keep the car long enough.

 

http://www.mofbody.com/blkchevyz/gxpfm.MOV


sorry for the poor quality the sun was so bright i couldnt see what i was recording.


regarding the flowmasters i'd go with a race series mufflers. the 1 and 2 chambers ones are pretty much just a hollow muffler with a V in the middle. not much of a restriction at all.

 

If youre going to do all that why not just better lesd restrictive mufflers in the first place i.e magnaflow spintech etc.

 

i personally like the sounds of flowmaster over the straight through, i think they have a deeper tone and less rasp. also i know the race mufflers don't hold back any hp, on my camaro i switched from dynomax bullet mufflers to some single chamber flowmasters and ran the same et... just a little quieter and sounded better doing it.

 

i contacted hogan for a full 3" full length OR DP and welded up my own full 3" into dual 3" catback utilizing 3 3" schoenfeld race mufflers. these are 6" long and like 3.5 or 4" diameter. absolutely zero packing in them. if you lay them on a quart of oil you can see the qt bottle on all sides still.

the sound is absolutely mind blowing. literally. it sounds awesome but is entirely too loud...however due to a nice lax law the catback and mufflers itself are completely legal in PA and the entire exhaust will be once the cat is grafted back in. i have a 3" magnaflow cat that is...umm...slightly modified...to place under the car.

 

I planned on using the Super 40, which is a 2 chamber and hardly restrictive compared to any non-racing muffler.

 

I also wanted to get a 3in hogan DP but can't seem to find their website anymore.

 

You have to use they're ebay store.

http://stores.ebay.com/Hogan-Performance

 

I have a catless 3" ZZP GXP 304SS downpipe for sale if you'd rather have that over the Hogan.

 

I gotta have a cat. Illinois does visual inspections.

 

What? Where? I never had a problem, and I've gone in with cammed and catless cars on a crappy hardly-running tune.