m05fastbackGT

I'm currently running Magnaflow Streets with stock cats and mid X pipe, however under 3k rpm in 4th-5th gears, inside the cabin is way too loud while outside the cabin isn't quite loud enough..

So I'm looking into replacing them with either Borla Stingers "S" type, Roush Extremes, Borla Atak's or SLP PowerFlo's.. IIRC these provide the least amount of cabin drone but also provide the best deep and aggressive exhaust tone which I'm looking for..

I'm sort of leaning more towards the SLP PowerFlo's as they're manufactured by Roush, but not quite as loud as their Extremes and also available in T-304 grade SS which I also prefer over T-409 SS..

Anyway I intend on sticking with both my stock cats and mid X and would like some opinions/feedback from anyone as to which would provide the least amount of cabin drone..


-Rocky

harleybill

Well I originally had the Borla's on mine and the drone at about 1600 rpm's was enough to kill somebody. I was at Summit Racing event and ran into Granatelli Motor Sports and ended up with their exhaust. No drone, great tone and as I like to say, not one of the many. You might look into that. Also looks great. Just something to ponder.

mustangman1960

I have the SLP Power Flows. I do not like them, they drone really bad around 2000 rpm. In 5th gear at 65 mph it is the worst.

m05fastbackGT

Thanks Bill, I'll definitely consider GMS along with my original 1st choice towards Roush extreme resonator muffler deletes..

Thank you for posting and bringing me up to speed regarding the SLP powerflo's.. Looks like I'll either be going with my original 1st choice with Roush extreme resonator muffler deletes or Granatelli Motor Sports recommended by Harleybill

07 Boss

Flowmaster Outlaws here with some mid-mounted Cherry Bombs. Went through a few exhaust set ups before I got it where I liked.

07 Boss

1600 Rpm's? Drop down a gear or drive faster. These motors like RPM's and hate to be lugged around below 2 grand.

wanted33

After listening to many different video's (I know they aren't dead on in sound), I have settled on the FR500S Ford Performance mufflers for my stock '06. The reviews are good, and best part is there is absolutely no drone at any rpm's. The wife has the FPP GT500 mufflers on her '13 5.0, they have a beautiful note with no rasp or drone whatsoever. They are a bit pricey, but if the quality is there like the GT500's they are well worth the dough. They are made by Borla, and sent to Ford performance for some tweaking. Also, they are the mufflers that came on the KR cars.

If you recall the car has pypes violators that were there when I bought the car. Nice, but they haven't given me a grin since I brought it home.

Jim

m05fastbackGT

Jim ! I actually started out with the Pypes Violators in polished T-304 grade SS.. Although you got really great quality and pricing, they droned really horrible under 2000 RPM especially in 4th and 5th gears..

At any rate, I still haven't quite decided on which axle back to settle on just yet, but from the reviews I've read and also from discussions I've had with CJ Pony parts, Roush Performance and from LMR performance.. They all seem to recommend the Roush Extreme axle back, muffler delete resonators

harleybill

Well it really was closer to 1900 rpm but that was cruising speed on the highway at the speed limit. Just where it liked to stay. Either way, the drone would drive you mad. People didn't like riding in the car. I loved the sound but the drone just wasn't worth it.

wanted33

Roush does make a quality exhaust, and the price is right in there with the rest. It's a tough decision as it's next to impossible to hear any of them in the wild.

m05fastbackGT

You're exactly spot on, as listening on sound clips and hearing them up close and personal are 2 different things altogether.. Being that CJ Pony Parts is closest to my area, perhaps they might be willing to let me hear what the Roush Extreme axle backs sound like at their store front on one of their test vehicles lol.

harleybill

Here is my engine getting dyno'd. Gives you an example of how it sounds with the Granatelli Exhaust.

wanted33

Wow Bill, that reminds me of time trails at the Charlotte Motor Speedway. Very nice.

m05fastbackGT

Very impressive indeed Bill

berzerk_1980

That does sound nice.

Gigantor

If you want loud and no drone, try Pypes Pype Bombs. I love the sound and it's not to obnoxious. I had the SLP Loudmouths but the drone drove me crazy.

m05fastbackGT

I've also looked into Pypes pype bombs.. My issue with Pypes however is fitment.. When I had Pypes Violators on my previous 05GT, the passenger side didn't line up with the driver's side.. Ended up taking the car to a muffler shop and having the passenger side hanger heated, then re-adjusted in order to line up and match the drivers side.. Since then, my confidence in Pypes has diminished to say the very least

wanted33

Rocky, I've got a set of the FR500's in the basement, and if it warms up enough that my old bones won't get so cold I'll get them on. I was disappointed in the packaging from Ford Performance though. They came with a bit of wrapped styrofoam between the mufflers, and that's all. After UPS got through handling them one of the pipe ends was through the box, with the end tabs bent some. Luckily I was able to straighten them out with some channel locks. I have let American Muscle know this ( they ship 'em as they get 'em) just in case they aren't as straight as I think they are. However the exhaust are quality built, but they should be at the price they cost.

BTW, have ya dug out from under all that white stuff yet?

m05fastbackGT

Hey there Jim ! You would also think being as much as Ford Racing charges for the FR500's, they'd include much better packaging in which any part of the pipe material sticking out of the box is totally unacceptable IMHO.. Anyhow I'm glad that AM stood up to the plate and provided you with an explanation, so my next step would be to contact Ford Racing and let them know they need to do a much better job when it comes to packaging their products.. I also hope there are no damages to any portion of the mufflers including any bends to the hangers, as I'd really hate for you to have to return the FR500's back to AM only to have to go through the same hassle over again..

At any rate, until Ford Racing provides better packaging quality, I'd much rather purchase from another manufacturer that does exactly just that for their customers.. In the meantime, let me know how everything turns out with the installation once the weather gets warm enough lol. As for the storm, we were lucky enough that it bypassed us and only got under 1 inch to just a coating.. However the temps are bitter cold with highs in the low to mid 20's..

Gigantor

I also had a set of Violators on my GT and they didn't line up right either. They were ok for the price, I got them off of Amazon. They sounded ok but not loud enough and I could never get them lined up evenly. However the Pype Bombs were much better and lined up just right.