Larmo

Installed Mac Off-Road Prochamber today to go with my FRPP GTA mufflers. THANK YOU Scott for your old Prochamber! Overall very happy, although I have mixed emotions.

Startup revs are wonderful.
Increased volume is fantastic.
Deep rumble at idle is incredible.
WOT is another story.

At WOT it gets messy... I'd describe it as snap-crackle-pop"-ish... and I have to think that the GTA's may be at fault although I'm not sure. The overall tone sounds a little "tinny". Anyway, you be the judge.

The guys at PMP did the install... awesome guys and I recommend them to anyone. Anyway, the jury is still out but I really like the overall tone and increased volume that my new Prochamber provides.

Here is a couple clips, let me know what you think.

http://www.youtube.com/watch?v=ND-uhV8Jkb8
http://www.youtube.com/watch?v=bnQn1ce_qkU

Spent 3 hours detailing her today and then it rained, go figure.

70MACH1OWNER

Ha Ha Dan... Welcome to the great exhaust debate! Removing the cats opens up a whole new world as you are finding out. I would agree that the GTA's can have a tinney sound to them at times but they still don't drone. Try them for a while. And like I said in my PM. Put your stock mufflers back on. I bet you will be impressed just how good they sound with the cats removed.
Scott

Larmo

Thanks, I wish I had a garage full of inventory where I could swap out a bunch of options until I found the sound I'm looking for!

JonCo

It does sound like much more air is flowing through the systems for sure. From the videos perspective it sounds great. After I heard Scotts videos with the prochamber I fell in love with it. Beats any o/r H or x pipe IMO

Error404

I bet putting the cats back in would tone back the popping

m05fastbackGT

Perhaps resonators, or straight-thru designed axle backs, such as Pypes Violators. might also do the trick as well.

70MACH1OWNER

I agree with this. What I have found is most mufflers systems develope a raspy, cackle/popping sound when you remove the cats. I mean effectively you are now running straight pipes with no restrictions from the front to the back. You really wouldn't like it with a standard H-pipe. It would be worse. The Prochamber helps mellow it some. And I also agree that resonators will help. Tom281 put them on his car because he didn't like what his Borla's sounded like running an offroad H-pipe or X-pipe. Bottom line is it is not the mufflers fault. Dan (Larmo) described the sound at WOT like a rattling sound. I believe what you are hearing Dan is called trumpeting. It is really bad now with my OBX longtubes and H-pipe setup.

sams66

I think it sound good, nice and aggressive. It is always hard to tell what it sounds like unless you hear it going down the road. My flowmasters i dont think sound all that great from the drivers seat, but when my wife takes a run down to the store or whatever in it, I am happy the way it sounds. However, if I was to do it all over again, I think I would go Borla, FRPP stingers.

Sam

Larmo

Today we went cruising and I think its starting to grow on me. One thing I've noticed, and its probably a very obvious observation, that the exhaust note is very different from the cabin when the top is down. Honestly, when the top is up it sounds awesome from inside. I'm still not in love with the snap-crackle-pop at extreme WOT.

You all make valid points about submitting clips out of the garage. I will try to get some drive-by clips soon.

In the meantime, please speak up if anyone thinks the tone will deepen and be more smooth with an alternate muffler. How about Corsa? Flows? Booms? Would like to stay away from Stingers as I do not want drone.

Thanks guys...

davesiar

Do not do Corsa's! They have no drone and sound good with the cats, but without cats.......AWFUL. I have an O/R H, and I have had 7 different sets of axlebacks on trying to find the "PERFECT" sound. I had the stockers on first and they sounded good, I then switched to Corsa's, and they sounded like a mix between a riding lawnmower, a Harley and one of them there hillbilly diesel trucks at WOT. I then switched to Stingers, same as the Corsa's, but a lot worse, and a lot of drone. I then switched to Flow's and they sounded awesome, but not perfect. I then switched to Magnaflows and they were too quiet. I then switched to Mac's and they sounded good also, but the Flows sounded better, so that is what I decided to go back too. I am now in the process of finding a prochamber to go with the Flows, because I heard it sounds amazing. Just my .02!

Larmo

So you recommend Flowmasters, eh? What would you say to the concerns about quality with flows around here lately? Where did you hear that Prochamber and Flows sounded awesome? You can send me your flows and I'll test the sound for you!! ;-)

turbo05gt

I ran the PC with Bassani's and LOVED it.

Larmo

"ran" as in past-tense? Why did you change?

shwaco1967

The sound I would like to get is that of the fox Stangs with flowmasters. I don't have the kind of funds for trying out 33 different combos, plus I have to keep the cats on for emisions. I've heard some sweet noises on the clips but never in person, yet never the sound to where I could say; "That's it!!!" So I'll just stay stock. But IF anyone ever gets that fox/flow down, it's gonna be on..

turbo05gt

Im taking them off for a true 3" for the turbos.

davesiar

Yes, I recommend Flows, but that is my personal opinion. Like I said before, I have already ran 7 different exhaust setups, and that was the best in my opinion. I heard about the Flow's and Prochambers from some other folks on different forums. They told me they were running Flow's with an O/R H and they liked it, but the prochambers got rid of most of the trumpeting that comes from the o/r h and it also mad it a deeper more aggressive tone. If you have the funds, play around with different setups and see what you like best. You could always buy and sell, like I'm doing until you find what you like best.

Darth Stang

Nice setup, Ihave almost the same on mine, just kept the cats! It's one of the best combos, but be careful about putting resonators on, it'll be like having two sets of mufflers on. Are you getting a lot of exhaust smell in the cabin? That's why i went back to the cats...

m05fastbackGT

Have you considered Pypes Violators ? Although I still use the stock H-pipe. I haven't experienced any drone at all. Also DarkfireGT. has them with the Pypes off-road H, and hasn't noticed drone either.

I can also assure you that even though the Violators, are not a chambered designed muffler. It uses a louvered tube design, that include mini-sound deflectors. which are similar to a chambered muffler.

Shortly after installing my Violators. I did a side by side sound test, between my 05 GT. and a friends 06 GT. with Mac axle backs.

Needless to say, after the results. The Mac's were noticeably louder, than my Pypes Violators.

Meanwhile, we both use the factory H with cats.

Anyhow. I've been running mine for almost a year now, and have been very pleased with both the sound, and overall design quality.

davesiar

I did consider running Violators until I talked to Pypes at SEMA, and they didn't really know what they were talking about and didn't seem very interested in being there. Also, I have heard numerous accounts with people having to cut the hangers to get them to fit under the car.

m05fastbackGT

I totally agree about most of their employees, not knowing what their talking about. Which is why I only request to speak to Mike, who's both the owner and designer for Pypes.

I'll also admit, that I had a really difficult time in getting the driver's side hanger to line up at the proper height.

So after finally getting fed up with messing around with them. I took my car to a local muffler shop. And all they did, was rotate the over the axle pipe, and then the muffler. In which it took them only 10-15 min. in order to get everything lined up properly.

Meanwhile after trying to line them up for 2 days, off and on, being on my back. I wasn't able to get anywhere.