2011-2014 Ford F150 3.5L / 5.0L / 6.2L Diamond Eye 4 inch Stainless Steel Single-Exit Cat-Back Exhaust - No Tip | K3330S

2011-2014 F150 Diamond Eye 4 inch Stainless Steel Single-Exit Cat-Back Exhaust - No Tip - 2011-2014 F150 Diamond Eye 4 inch Stainless Steel Single-Exit Cat-Back Exhaust - No Tip
2011-2014 F150 Diamond Eye 4 inch Stainless Steel Single-Exit Cat-Back Exhaust - No Tip
SKU K3330S
27 Review(s)
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Average Rating
2013 f150 super crew 5.5 bed 5.0v8
Great exhaust. Fit perfect, sounds awesome. They're is a little drone at highway speed but it's nothing to drive you crazy. Great system for the price and really brings the 5.0 to life.
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Reviewed by:  from Cincinnati Ohio on 7/6/2014
5
Average Rating
MR.
Easy to install , and it sounds great ! The Ecoboost is an awesome engine and this exhaust really brings it to life .
Did you find this helpful?  9 of 11  Found Helpful
Reviewed by:  from Quincy IL on 7/21/2013
5
Average Rating
2010 F150 5.4L
I have a 2010 F150 5.4L. This kit was not made from my engine configuration. However with $15 I got an adapter I was able to make it work. Couldn't be happier with the sound. The tone is very deep. I went from Flowmaster outlaw to this hopes of less highway drown. It worked perfectly. Couldn't be happier with my purchase. Perfect exhaust system.
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Reviewed by:  (Verified Buyer)  from Texas on 8/24/2021
5
Average Rating
2012 F150 5.0
Sounds amazing with the 5.0 and most importantly there is little to no drone, only noticeable at 1900 RPMs. Only reason it's not 5* is because I needed to cut a clamp 3/4 shorter to make it fit right but that's the only complaint I have.
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Reviewed by:  from Minnesota on 3/19/2015
4
Average Rating
2014 Ford FX4, 5.0 Liter V8
Great deep exhaust sound without the rasp. Just what I was looking for. Sound inside the cab is agressive and sounds good on the gas and settles out nicely. Like most systems, there is slight drone at around 1800/1900 but minimal in my experience. Happy wirh my decision.
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Reviewed by:  from Coastal Ga on 4/17/2015
5
Average Rating
2012 Ford F150 XLT 5.0
Additional Equipment: K&N CAI When I first installed this system, I had to readjust the flange several times before it was equally sealed. The stock exhaust manifold has a 3 inch flange and a 2.5 inch pipe, so it takes a bit of time to get it right. When you first start it, it is LOUD. It does mellow out considerably after a few hundred miles, but it echoes and resonates in the cab until then. If you are coming from a stock setup, this is going to take some getting used to. HOWEVER, after ~200 miles, it is almost silent at idle and cruise speeds, roaring to life when I hit the gas. This is exactly what I was looking for when I purchased this exhaust. I am glad I stuck through the break-in period, and I would now (obviously) recommend this cat-back system to anyone looking for that subtle roar on their F150.
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Reviewed by:  from Cincinnati, OH on 4/25/2016
5
Average Rating
2012, ford, fx4 screw ecoboost
I've had it on for a week now and I love the sound of it on my Ecoboost , really brings a little boost of performance along with my AFE CAI. seems like right off the line I get off about the same maybe quicker but when the rpms start increasing u can really feel the extra push. inside the cab it's a little loud, but nothing that will drown out a conversation or music. it sounds louder and a lot more throaty. May wake the neighbors some days but it's not too bad. I can stand around back my house lock the truck and auto start, hear the cold start pretty loud but the sound then dies back down. Mph may have increased by .5-1.0 hard to tell by the way a drive. Installation wasn't too hard to figure out like most say, getting off the stock took longer then installing the new piping, idk what some people say about getting it off by there selves, no lift, no jack, nor jack stands. If your at stock height, there's no way to get the stock exhaust off without cutting it unless it's jacked up. Two men make the job a lot easier and jack stands come in handy when installing the pipes to rest them on the jackstands at a level height. Just my two cents. the stainless steel looks great. I got a 5 black exhaust tip along with this and it looks great. I like being able to see the thick shiny piping going over my axle. Overall diamond eye did good with this product, came with everything needed, and the additional pipe if you have a longer wheel base (which I dont). Thanks stage three. Also there is a great installation video on YouTube just search Diamond eye ecoboost installation and there's a 15 minute video of a deisel shop installing this exact exhaust.
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Reviewed by:  from Maryland on 1/20/2015
5
Average Rating
2011 F-150 FX4 Ecoboost Supercrew/6.5' Bed
Awesome exhaust fits perfect,took a couple of hours with a buddy to install.Clamps are very good and secure. Sounds great, no drone in cab at highway speeds, good rumble at idle, definitely noticed fuel improvement,1-3 mpg, sounds good when romp on it and you can hear turbos singing!! Best exhaust and the best $
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Reviewed by:  from Independence,MO on 8/16/2014
5
Average Rating
2012 F150 5.0 Screw
Installed by myself in less than 2 hours. Sounds great, it is a bit loud until it breaks in. Very nice sound, sounds a lot like the video clip stage 3 has on it. It's there and lets everyone know you have a v8 when your accelerating quickly then let off and it's quiet. Very pleased with the exhaust and quality of the exhaust system.
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Reviewed by:  from Idaho on 4/17/2017
5
Average Rating
2015 F150 supercrew
Took about an hour to install. Flange was a little bit of a hassle but well worth the price! This kit fits 2015-2017 fine!
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Reviewed by:  from Wisconsin on 4/20/2017
5
Average Rating
2014 f150
Great exhaust and sound for the price. Just have to make sure the flange is lined up perfectly but all you need is a buddy to help you out on that. Sounds sick
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Reviewed by:  from Cape cod on 10/5/2015
5
Average Rating
2014 F150 6.2L
Great product and the sound is amazing. Perfect fit for my CCLB pickup.
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Reviewed by:  from MI on 12/23/2017
5
Average Rating
2014 F150 3.5L
I really like the sound of the exhaust. There's a little drone from 2000-2500 or about 70-75mph. Thinking about adding the Diamond Eye resonator down the road. See how it goes after the exhaust burns in. The directions could be better as to which way the hangers need to go. The extension pipe did need to be cut for the size of the truck, 2014 3.5L crew 6.5' bed.
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Reviewed by:  (Verified Buyer)  from Indianapolis on 2/22/2018
5
Average Rating
2011 f150 ecoboost
Extremely nice product! Packaged well, and came undamaged and fast. Had a local muffler shop install for a $100 bill and said he wanted to know the name of it because all the others he's installed were not as easy and most importantly didn't sound as good as this one. I have a edge programmer and a banks cold air intake and the edge programmer does not allow for custom tunes and I think that's what I need. When I really get on it it falls on its face then turns into a rocket ship and back and forth until I back off some. I'm no mechanic but I suspect with all the freedom of air out isn't allowing enough back pressure for the turbos or the air fuel mix is off with the 4' exhaust. If anyone has experience with this and can tell me, please help me? Otherwise a great kit! Especially for the money!!
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Reviewed by:  from Oklahoma on 8/15/2018
4
Average Rating
2013 F150 3.5 ecoboost
I bought this setup because it was budget friendly. I like the noise it gives, which in my opinion isnt too loud as others say. Looks good, and fit perfectly. Took literally 30 min to install laying in the garage.
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Reviewed by:  from SAINT JOSEPH on 3/3/2019
5
Average Rating
2013 F150 STX 5.0
This exhaust has been awesome so far. It has the deep aggressive throaty sound I was looking for but isn't overwhelmingly loud. I have a S&B CAI and tunes from FiveStar but I haven't driven enough to notice much in MPG change yet, if there will be any. Definitely a great buy for the price.
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Reviewed by:  from Tallahassee on 10/11/2015
5
Average Rating
2011 Ecoboost
Awsome exhaust, Stainless steel is the best material to use on exhaust systems period! This exhaust is just as free flowing as any other name brand out there. With the use of an AFE STAGE 2 induction I've personally improved 2.5 to 3 mpg on high way
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Reviewed by:  from KCMO on 11/28/2014
5
Average Rating
2012 F-150 FX4 Ecoboost
Great exhaust system. It has a bit more of a growl then the stock, but does seem to help the engine breathe a bit better. I am running it with an Airaid CAI and no tune...yet.
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Reviewed by:  from Omaha, NE on 5/7/2014
5
Average Rating
amazing sound
Glad I went with this exhaust I have no complaints it sounds great not all tuner out. Noticed a huge difference right away increased mpg. Great for the money don't know why you would go with anything else. Install was very easy and simple.
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Reviewed by:  from texas on 7/12/2014
5
Average Rating
2014 Ford f150 FX4 Ecoboost
This exhaust is really easy to install and sounds great! Give you that sound you're looking for and at highway speeds you barely hear it. Very little drone in the cab when cruising but when you punch it, it wakes up. Defintely felt a power increase with this and the afe cai I installed with it. Would defiently recommend this exhaust to anyone with an ecoboost.
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Reviewed by:  from Spring Branch, Tx on 2/20/2015
5
Average Rating
Ford F150
Doesn't sound bad at all. Install was quick.
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Reviewed by:  (Verified Buyer)  from Geneseo on 10/17/2017
5
Average Rating
2014 Ford F150
Excellent exhaust system. Some people said that one of the exhaust hangers hits the drive shaft if this is the case,it was installed wrong. I installed this kit in an hour taking my time. There is more than enough room between the exhaust hanger and the drive shaft. Thanks Stage 3 for fast shipping and excellent service!
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Reviewed by:  from Ks on 4/30/2016
5
Average Rating
2011 F150
I read a lot of reviews when I started my exhaust search. I watched all of the Stage 3 exhaust video clips. I finally decided on this kit based on the other reviews on here. I opted for the stainless exhaust tip also. Install took about an hour and half. I only needed a 10mm socket, a 14mm socket, a 9/16 socket and a 9/16 wrench. I opted for cutting my OEM exhaust in 2 places; right after the resonator and right after the muffler. I chose to do that for 2 reasons. 1 - I was installing this with the truck on the ground and by myself, and 2 - My OEM clamps were seized with rust. Old exhaust was out in less than 15 mins. Mocked all of the new exhaust pipes into place per the Diamond Eye instructions. Once I was happy with the placement, I started at the flange end and tightened everything down. There is a little bit of drone when you are on the gas but I have read that this will diminish after the initial 200 mile burn in of the muffler. Once again, VERY happy with Stage 3! Ordered this kit on a Sunday night and it arrived Wednesday afternoon.
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Reviewed by:  (Verified Buyer)  from WI on 3/5/2017
5
Average Rating
2014 f150 xlt 5.0
Love the sound of the exhaust. So far the only draw back is that I live In the mountains and the drone gets kinda loud going uphill nothing terrible but long trips can be a little annoying. The radio kinda drowns it out. Other then that I am completely satisfied with my purchase. I would recommend it to anyone with the 5.0 it's worth it!
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Reviewed by:  (Verified Buyer)  from Sylva nc on 4/28/2019
4
Average Rating
2011 Ford F150 3.5 ecoboost SuperCrew
Gains in mileage, HP and SOUND. Wife HATES it. I Love it. Easy to install.
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Reviewed by:  from Morristown on 3/2/2020
5
Average Rating
2014 F150 FX4 3.5l ecoboost
The 4” exhaust looks great on the truck compared to stock and sounds pretty good for v6 too. It has a deep low tone, and I can hear the turbo whistle now as well. Installation wasn’t too bad. I think It took me longer to get my stock exhaust off than it did to put the new one on. Overall I would recommend this exhaust. The quality and sound seems pretty good for the price.
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Reviewed by:  from North Carolina on 1/26/2021
5
Average Rating
F150
Old exhaust built by backwoods muffler shop finally rusted out so went this route. CC SB and think they change some hangers around on it when they installed the crap exhaust so I had to use the intermediate pipe for my install. Great sound with the 6.2. Doesn't drone at all.
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Reviewed by:  from TX on 11/9/2025
5
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Customer Question Will this fit a 2010 F150 5.4L

Asked by: William Vog - 7/25/2021
Customer Answer This kit will not fit a 2010 F150 5.4L. The closest Diamond Eye has for the 2009-2010 F150 5.4Ls is their 3.5" Cat-Back Kit here.
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Answer provided by: Jason@Stage3 (7/26/2021)

Customer Question I am looking at the ar long tubes with the resonator delete. Does this have the ability to be fixed to that pipe easily? I can’t tell if it has a breaking point after the ball cup design for the factory resonator location.

Asked by: Coty - 3/24/2021
Customer Answer I'm not sure what you mean by "AR". The American Racing headers are designed to work with the stock cat-back kit, and this system will work with them. If you mean a different set of headers that do delete the stock resonator, this kit will not work with a step-down connection and custom modifications.
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Answer provided by: Jason@Stage3 (3/26/2021)

Customer Question Does it matter which direction the muffler goes on? Do the louver catch air flow and pull it into the fiberglass packing or do the louvers protect the packing. The instructions say there is an inlet and outlet, but there are no markings on the muffler.

Asked by: Nantus - 12/14/2020
Customer Answer You can actually install the muffler either way. If you install the muffler with the open-side of the louvers toward the front of the truck, the kit will be a smidge quieter than otherwise.
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Answer provided by: Jason@Stage3 (12/15/2020)

Customer Question When installing the muffler I noticed it had raised metal ridges inside going in a swirling pattern. One side of the ridges is smooth and the other is concave. I installed it so that the exhaust gases would flow over the smooth side of the ridges but am curious what would happen if I had installed it the other way around. Any ideas?

Asked by: Loham - 3/12/2019
Customer Answer The sound of the kit would be slightly quieter. The muffler is bi-directional, so you could put it on either way. With the interior cutouts facing away from incoming exhaust, you end up with a slightly louder tone than if the muffler were reversed. There wouldn't be a massive impact in regards to backpressure or performance.
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Answer provided by: Jason@Stage3 (3/13/2019)

Customer Question It does not state in the instructions. Does this muffler have a flow direction? I see the internal design of the muffler and would assume the raised open ridges face the front of the truck? Want to make sure it's right. Thank you

Asked by: Roger - 2/12/2019
Customer Answer You can actually install the muffler either way. With the internal openings facing the front of the truck, the kit will be a bit quieter. With the sealed side facing the front of the truck, the kit will be a bit louder.
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Answer provided by: Jason@Stage3 (2/13/2019)

Customer Question Will this fit on a 163" wheelbase?

Asked by: TARO PINE - 11/28/2018
Customer Answer Yep. Diamond Eye includes an extension pipe that allows it to fit on 163" wheelbase F150s.
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Answer provided by: Jason@Stage3 (11/29/2018)

Customer Question Will this bolt onto the solo downpipe? If not, can you recommend a decent catback that will?

Asked by: Keithan - 4/2/2018
Customer Answer This cat-back should fit Solo's downpipes without any issues. The Solo downpipe is designed to fit a stock cat-back or a stock replacement, and the Diamond Eye cat-back is designed to fit with the stock downpipes or a stock replacement.
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Answer provided by: Jason@Stage3 (4/3/2018)

Customer Question Will this fit a 2014 f150 5.0 157" wheel base?

Asked by: 2014 157 - 8/25/2017
Customer Answer Yep. This cat-back kit will fit all F150 wheelbase sizes, though it will require some trimming of its extension pipe in order to fit on a 157" wheelbase F150.
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Answer provided by: Jason@Stage3 (8/28/2017)

Customer Question Will this fit a 2012 f150 supercrew 5.5 bed? Or will trimming be involved?

Asked by: Justin - 4/18/2017
Customer Answer This kit does not require trimming on F150s with a SuperCrew cab and 5.5ft bed with a 145" wheelbase.
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Answer provided by: Jason@Stage3 (4/19/2017)

Customer Question Two questions here: 1) I live in Colorado. It's very dry here, but the DOT uses lots of salt and mag chloride to melt ice on the roads, which has proven to be corrosive for the undercarriage on previous vehicles. Is it worth going with the stainless version, or will I be ok with the aluminized? 2) How noticeable is the loss in low end torque on the 4"? Enough to go with the 3.5"? It's worth noting that I don't have a CAI or a Tune... Thanks for your help!

Asked by: Jace - 1/12/2017
Customer Answer 1). In any place that uses salt during the year, we recommend getting at least a 409 stainless system, if not a 304. Salt can really eat away at aluminized kits. 2). Not overly noticeable. You may feel a slight dip, but it's not usually enough to effect your overall drivability.
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Answer provided by: Jason@Stage3 (1/13/2017)

Customer Question Will this exhaust fit the 09-10 5.4?

Asked by: Nick - 1/2/2017
Customer Answer It will not. Diamond Eye does have a 3.5" Cat-Back Kit specifically for the 2009-2010 F150 5.4Ls, however.
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Answer provided by: Jason@Stage3 (1/3/2017)

Customer Question Will this bolt up to the oem down pipes on 2011 f150 3.5l?

Asked by: Brian - 12/3/2015
Customer Answer The Diamond Eye kit fits the 2011 F150 3.5L EcoBoost's factory downpipes.
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Answer provided by: Jason@Stage3 (12/3/2015)

Customer Question I just bought this exhaust and it's great so far! I did notice a slight drop in low-end torque (which was expected with such a large diameter pipe). I have tunes from FiveStar already for my S&B Cold Air Intake I bought from y'all, but my question is does this 4" exhaust require a new tune because it's a whole inch bigger than stock on the 5.0?

Asked by: Nick - 10/11/2015
Customer Answer A new or revised tune is not required for this kit.
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Answer provided by: Jason@Stage3 (10/12/2015)

Customer Question I am between buying this pipe or the Solo Performance 4" single exit cat back. I understand the Solo cat back has a J-pipe to eliminate drone. How bad is the drone with this pipe? I would love to get the solo but I don't know if I can justify spending double the price of the Diamond Eye for a J-pipe. Thanks

Asked by: Nick - 8/30/2015
Customer Answer Drone with this kit is noticeable, but not terrible at all. The Solo MR400 kit is much more aggressive overall than this kit, and that J-Pipe is a must to keep drone down, but even with the J-Pipe, you'll still have some amount of drone.
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Answer provided by: Jason@Stage3 (8/31/2015)

Customer Question What is the difference between this 4 in cat back exhaust and the 3.5 in exhaust? What are the benefits of one over the other?

Asked by: Kevin - 8/23/2015
Customer Answer There's a slight difference in sound, with the 4" kit being slightly deeper and more aggressive. You can see a slight drop in low-end torque with a 4" kit, depending on your tuning, while you generally won't with a 3.5" kit.
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Answer provided by: Jason@Stage3 (8/24/2015)

Customer Question Before buying this exhaust. Will it fit the 126" WB standard cab, regular 6.5 bed truck?.Thank you.

Asked by: 2013STX - 3/30/2015
Customer Answer It will fit, but it will require trimming, according to Diamond Eye's instructions.
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Answer provided by: Jason@Stage3 (3/30/2015)

Customer Question When installing this, will it make the check engine light go off when deleting the resonator, think also known as cats? Thanks Jason!

Asked by: F-150 man - 3/19/2015
Customer Answer This kit will not set off your check engine light. The catalytic converters are in the mid-pipe assembly, which is forward of the resonator. These trucks' factory resonators are simply there to tone down sound, and don't have effect on emissions.
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Answer provided by: Jason@Stage3 (3/19/2015)

Customer Question Will this unit fit on a 2011 XLT supercab(non 4-door) 5.0L? I see all the FX4 reviews but no XLT with 145WB, please advise, I would like go buy this system.

Asked by: Sam Griswold - 3/5/2015
Customer Answer This kit will fit your truck. Submodel does not affect the fitment of this kit, and it's designed to fit all wheelbase sizes. So, if you have a 145" wheelbase by way of a SuperCab with a 6.5 foot bed, this kit will fit your truck just fine.
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Answer provided by: Jason@Stage3 (3/6/2015)

Customer Question Will this exhaust system bolt up to a 3.5" cat pipe?

Asked by: Shane - 2/26/2015
Customer Answer Not out of the box. Custom modifications would be needed, if you're planning on using an aftermarket Y-pipe that's larger than stock.
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Answer provided by: Jason@Stage3 (2/27/2015)

Customer Question does a 3" give the 2014 ecoboost more power than the stock exhaust?

Asked by: al - 1/31/2015
Customer Answer Power gains with a cat-back system alone are going to be marginal, regardless of its diameter. Peak power does tend to improve slightly with a larger diameter cat-back kit, but only by about 5-10hp at the crankshaft.
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Answer provided by: Jason@Stage3 (2/2/2015)

Customer Question Does this system use the stock resonator and is cutting required to fit the 145" WB?

Asked by: Kevin - 2013 F-150 5.0L - 4/4/2014
Customer Answer This kit deletes the stock resonator and can fit 145" wheelbases without any cutting.
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Answer provided by: Jason@Stage3 (4/8/2014)

Customer Question Are you planning on posting a video of this kit?

Asked by: matthew plummer - 2/12/2014
Customer Answer We actually did shoot some video, but had issues with the video itself. In any case, we're going to reshoot it here soon and get a proper video up. Sorry for the delay!
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Answer provided by: Jason@Stage3 (2/21/2014)

Customer Question is this quieter than the solo single 4"/with the mach-46?

Asked by: matthew plummer - 2/10/2014
Customer Answer Yes, on the 5.0L this is quieter than the Solo single even with the MACH46 muffler.
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Answer provided by: Administrator (2/10/2014)
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WARNING: Cancer and Reproductive Harm

This product can expose you to chemicals including those known to the State of California to cause cancer and birth defects or other reproductive harm.

For more information, visit [www.p65warnings.ca.gov](https://www.p65warnings.ca.gov).

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