Just installed a pair of Borla Pro XS

[drj02]

Anyone else have a set of Borla mufflers on their Marauders? I have always been partial to Borla's specific tone. Just my preference I guess. I have heard Borla's on the 5.0 and 5.4 and love the sound but never had experience with the sound on a 4.6 per say. They don't make a so called "tuned cat-back" set up so I installed the Pro XS universal mufflers. The rest of my exhaust is stock. I tried to look for You Tube videos but could not find any that were direct comps to check out. A little scared at the moment. They were less noticeable in sound than stock when I left the shop tonight. Called Borla and they mentioned that there is a 500 mile break-in period. Do mufflers open up a lot if manufacturers state break in period or is it a suttle difference from brand new? Any thoughts on this? Got my fingers crossed. :dunno:

[bob6364]

I have notice a difference in sound on my SS mufflers...they did get louder.

[MM_BKK]

Your mufflers are not going to get any louder unless they have synthetic packing material inside which will get deteriorated over time.


I'm running 22" Dynomax reverse flow mufflers and 4 external resonators. I finally have the exhaust set up that is quiter than stock!
I love sneaking up on unsuspecting new cars with only the Whipple whining! They don't even know what just hit them! :D

[drj02]

Thanks for your input. I am a bit scared that I made a poor choice at the moment and should have just left the factory mufflers on. I have never been disappointed with Borla on any application in the past. Suppose I should give these a chance of break-in before I make a final take on the issue. It's tough because I can't seem to find a lot of feedback or video clips online to say one way or another. Hope more will express their thoughts positive or negative, it's all good info. to me.

[MM_BKK]

Are you looking for much louder sound than stock?

[drj02]

No, not really louder per say but more defined and consistent throughout the entire power band I guess if that makes sense. I liked the factory sound but would like to hear a more defined rumble at idle. That's one aspect of Borla I always liked. Matter of fact, I have a cat back system on my '08 F150 Lariat 5.4L and it's awesome! Borla's in my experience, always seemed to have a "rich" tone at all R's. After this install however, I think the sound is just silent and flat in comparison, boring, etc. Very surprised but as I mentioned, maybe this is just break-in and I need to be patient. Hope someone can confirm what this muffler actually will sound like long term.

[drj02]

Sorry folks, one additional question about these or any aftermarket mufflers for that matter. An install of aftermarket mufflers only with no other exhaust modifications (ie: headers, etc.), won't affect the performance in an adverse way right? Just wanted to be sure that it won't throw off the PCM somehow or some way. This could very well just be mental but I thought I had experienced on the way home from the shop tonight, a little acceleration decrease feel as well.

[FordNut]

Shouldn't affect performance.

I'm glad to hear they are as quiet or quieter than the stock mufflers, I'm going to be putting them on my car soon. I'm interested in flow and durability, not sound.

[drj02]

Well, I wasn't going to take any chances. I decided to go back to the shop today and had my stock mufflers re-installed. Much better now. Got my performance back and sound back to normal. I got all my money back but just had to pay $85 labor to reverse back to original mufflers. Not happy but better then the $313 if I kept and didn't like at the end of the day. Live and learn I suppose. I was on the phone again with Borla. Learned a lot about exhaust and it's effects. Never realized the complexity that makes up the final sound and performance quality. Thanks to all for their info. and insight on this topic!

[DJCV]

I looked seriously at Borla XS mufflers a few years ago. I gathered at the time that they flow very well and are remarkably smooth & quiet. Seems like the 'quiet' part is right on the money, based on your experience.

If you want a somewhat more defined tone, consider Magnaflows with 18" cases. If you run them for a while and still want it a little louder, who knows....maybe someone will suddenly 'steal' your rear cats.;)

[babbage]

Shouldn't affect performance.

I'm glad to hear they are as quiet or quieter than the stock mufflers, I'm going to be putting them on my car soon. I'm interested in flow and durability, not sound.


Power Highest to Lowest

1.Flowtech Warlock (open) 374.2 hp/ 333.1 tq
2.Bassani Real Street 373.7 hp/ 333.8 tq
3.Hooker Maxflow 373.5 hp/ 333 tq
4.Borla XS 373.3 hp/ 332.6 tq
5.Magnaflow 372.8 / 332.5 tq
6.MAC 372.3 hp / 331.5 tq
7.Flowtech Afterburner 372.3 hp/ 330.1 tq
8.Hooker Aerochamber 372.1 hp/ 330.4 tq
9.Bassani 372 hp/ 333.5 tq
10.Spintech 371.6 hp/ 332.2 tq
11.Edelbrock Performer RPM 370.9 hp / 331.3 tq
12.Borla XR1 370 hp/ 334 tq
13.Flowtech Terminator 369.5 hp / 331.3 tq
14.Dynomax Ultra Flo 369.4 / 333.2 tq
15.Flowmaster 369.4 hp / 331.8 tq
16.Flowtech Warlock 366.3 hp / 325.3 tq
17.No muffs 365.2 hp / 330.1 tq

Sound Off in Quietest to Loudest (Decibels):

1.Borla XS, 80db at idle, 90db at 2,000 rpm, 110db at WOT.
2.Hooker Maxflow, 80db at idle, 90db at 2,000 rpm, 120db at WOT.
3.Magnaflow, 82db at idle, 91 at 2,000 rpm, 114db at WOT.
4.Flowmaster, 82db at idle, 93 at 2,000 rpm, 115db at WOT.
5.Flowtech Warlock, 83db at idle, 92 at 2,000 rpm, 112db at WOT.
6.Dynomax UltraFlo, 83db at idle, 94 at 2,000 rpm, 113db at WOT.
7.Borla XR1, 83db at idle, 96db at 2,000 rpm, 118db at WOT.
8.Bassani Street, 83db at idle, 96db at 2,000 rpm, 120db at WOT.
9.Edelbrock RPM, 84db at idle, 93db at 2,000 rpm, 118db at WOT.
10.Bassani Real Street, 84db at idle, 96db at 2,000 rpm, MAX. (120+db).
11.Flowtech Afterburner, 86db at idle, 94db at 2,000 rpm, 115db at WOT.
12.Flowtech Terminator, 86db at idle, 94db at 2,000 rpm, 119db at WOT.
13.Hooker Aerochamber, 87db at idle, 94db at 2,000 rpm, 114db at WOT.
14.SpinTech, 87db at idle, 97db at 2,000 rpm, 116db at WOT.
15.MAC, 87db at idle, 98db at 2,000 rpm, 119db at WOT.
16.No Muffler, 91db at idle, 103db at 2,000 rpm, MAX. (120+db).

[JimP]

If you want it a bit louder and like the stock sound with more volume, remove the resonators located after the mufflers in the tail pipes. Buy the Meg's resonator delete tips.

[jonroe]

I put on the universal Borla Turbo Mufflers for small block V8s. My impression is the loudness is about the same as OEM mufflers but the tone is lower and richer. I never regretted the change. If you want loud, these ain't it. These are not the Pro XS mufflers.

[babbage]

I put on the universal Borla Turbo Mufflers for small block V8s. My impression is the loudness is about the same as OEM mufflers but the tone is lower and richer. I never regretted the change. If you want loud, these ain't it. These are not the Pro XS mufflers.


Yeah but do you have the Bolra Turbo Mufflers on your MM?

Word around that campfire is -- they have SOME drone -- which is a deal killer for me!

[Big Black Beast]

I put on the universal Borla Turbo Mufflers for small block V8s. My impression is the loudness is about the same as OEM mufflers but the tone is lower and richer. I never regretted the change. If you want loud, these ain't it. These are not the Pro XS mufflers.

Does anybody know off the top of their head what loudness the stock setup is?

[Vortech347]

So you'd rather stick a louder muffler on the car and go slower?