Exhaust Back Pressure and Diameter - Summit Racing Quick Flicks

[@sranjesuper]

Thanks, I installed a 4.5 Inch exhaust system on my 99 caravan

[@onetirefire1]

I hope true duals :-D

[@_ShaDynasty]

i just cut mine off. sounds really cool now

[@CoroPlanesLLC]

I put a 4.5" system on my Honda Odyssey because I wanted 1000HP....

[@TexasHarleyBoy65]

Don't forget your X-pipe.

[@Fingerboardmaster200]

I laughed at this

[@numinous4789]

Backpressure isn't the issue. Exhaust gas flow velocity is the issue. Ideal piping size is that which causes the fastest flow through it for maximum power. Too small piping chokes the system. Too large piping slows down exhaust gas velocity.

[@nos1000100]

too large also adds extra weight and noise

[@ILKOSTFU]

THX!!!!!!!!!!!!!!!!!!!!!!

[@brucepamplin8218]

correct!!! and his cup and paper trick is crap....if it was atmosphere pressure keeping the card on as he indicated then wouldnt it also do the same without the water in the cup....i think he has other forces at work like vaccum and sticky h20 not a good example....and forced induction would not even apply to his world...but it would in your explanation of choke points and gas velocity.....the exhaust is an extension of the heads really

[@AtariFTW]

Hit the nail on the head

[@XxTournaquetxX]

Facts.

[@outlander330cc]

I think the guys at Summit need to stick to selling parts and not making misleading videos. As an engine builder, you strive to tune the exhaust system so that negative pressure waves hit the exhaust valve as it opens in order to make the pressure at the exhaust valve BELOW atmospheric pressure to get more pressure differential and more flow. "Backpressure" just hinders flow and makes the engine less efficient in every way.

[@tobydozier9030]

@18 RLX Vibrant 7 DCT The scientist couldn’t haven’t said it better.

[@jonesvaughn8946]

@18 RLX FJBLGB question I have a 4 cylinder sedan with a muffler delete and Spec-D exhaust welded on if I did a resonator delete would I be hurting my engine if so how?

[@213gully]

@Honda K24 fJBlgB hey help me out. 2jzgte single exhaust system straight with on aero muffler putting out 700 whp how many inch piping?

[@outlander330cc]

@@FullSendFabrication The pressure wave is relevant no matter how long it is, it just has a smaller effect the longer the pipe is past the 3-4ft of header needed to get a good tuning effect. The pressure waves work like a tuning fork, it will start at your exhaust valve, travel all the way to the exhaust tip and hit atmospheric pressure and then reflect and go back to the exhaust valve as a low pressure wave. The longer the pipe is the more waves are in the pipe at the same time and the less effect they have. Kind of butchering the explanation but that's the most concise way I know to put it.

[@8790MikeHunt]

Absolutely. It's the same as claiming an air pump would benefit by restrictions in the flow path.

[@milkcollins4764]

Because of this video I just bought a 3” exhaust system for my 1.6l sohc motor because I want to sound like a fast vacuum

[@hotrodsurplus]

It boggles my mind that a business like Summit would consent to let someone who doesn't understand fluid dynamics instruct people on exhaust systems. Summit, please consult an expert. This just propagates myths.

[@Z1FU]

+unharmonix agree!!

[@daltomhawes213]

Wow finally found another smart human

[@rsar61]

hotrodsurplus are you telling us that you’re an expert?, it’s possible , you can be any kind of expert while pecking on your keyboard 🙄

[@davidseinen3483]

So is this complete video unreliable for power-size ratio?

[@AIR_RAM_PERF]

This "back pressure" wise tale has been passed around for over 50 years! "My grand paps great grand fathers brothers sisters ex husbands son inlaw said that he lost torque on his Model A street rod when he added dual exhaust... so naturally the loss of torque was because he removed the beloved back pressure... as soon as he added the smaller exhaust his back pressure returned and he made more power... LMAO! I honestly dont understand why more people dont have the slightest grasp on basic fluid dynamics... just a slight grasp would do wonders for most.

[@fabrb26]

2:45 Looking at this , all the 1500-2000hp Supra should get 15 in exhaust lol

[@rayray6966]

You're a good magician. Poor engineer.

[@velez910]

did this guy really just show me a test of vacuum and try to use that to talk about back pressure????

[@davidrayner9832]

Yes, he did.

[@qazqazqazqaz4]

daniel velez it's not vacuum, the same amount of air is still in the cup when he flips it over

[@velez910]

Mateo Gomez Gomez it is vacuum along with the vescosity of the water causing a seal at the edges of the glass to the paper. water is heavier then air it pushes down on the card. water is to thick and heavy for air to be pulled threw the edges. causing a vacuum

[@s.v.gadder1443]

Lmao I said the same thing wtf Chuck

[@CoroPlanesLLC]

Yup! I almost clicked out of the video at that point but it was like watching a train wreck... I just could not look away.

[@Steven_T4R_0731]

3” it is for my Geo metro...thanks Summit!!!

[@zragevii4705]

3 cyl? Triple pipe setup? You might want 4" for a beast like that.

[@elgatosamurai9517]

🤣🤣🤣🤣💀

[@puffnstuff12]

1 inch for each cylinder? 😁

[@grimeyhonkyracing3938]

Get a 3 to 1 collector that goes to 10"

[@L-Noble.YT_Hi.Res-Soundminds]

Look all engines react different to exhaust changes. On inline 4 and 6 if your piping is too big then the torque down low will be gone and feel sluggish but High rpm gets a little bump. V8s seem more forgiving but it is true that you need the correct pressure and velocity to have a good ballance of low end torque and output. This I have found on NA engines not boosted and from experience not reading books.

[@TheYoungerSemiOldMan]

For those bringing up NASCARS, etc. let's explain something so you understand how motors work. Johnny SIX4 !! Very simple. You have street applications and race. With racing you spend most of your time at high RPMs therefore the flow will be greater thus requiring less back pressure. Im street applications, since the RPMs will be lower most of the time, you need it so the scavenging effect takes place. Otherwise you'll have no torque on the low end and only extra horses on the top end like race cars. As a result you lose low end torque and ability to pull through the lower gears and RPMs. Let's not mention fuel economy loss. You NEED back pressure to create the scavenging effect more so in trucks. It's a large vehicle that requires torque to get the large body moving, not horsepower. Horsepower takes effect at the upper end of the spectrum where torque isn't required as much. Mustangs are light and have high output motors. Stop and go traffic will destroy your fuel economy BUT with a free flowing exhaust, your horses will be higher so in race applications where you're at almost redline, you'll notice the benefits. I don't know very many people that spend that much time at high RPMs while driving to work, so it's not the most economical. You choose how you want your pocket book to go. Poor fuel until you hit redline or decent fuel the way the car was designed and sacrifice the upper end. Take your pick, you can't get both. How that answers your questions and clears your confusion....

[@robbiejones3790]

Choosing the right diameter exhaust pipe is to make sure the exhaust gas temperature and velocity stay up. Back pressure is created when your engine is pumping out more air than what your exhaust can handle, as opposed to the partial vacuum created by exhaust scavenging...duh

[@JoeIsCrazyWillman]

Basically your engine has to FORCE your exhaust out, so your engine loses some power because of that, particularly at upper rpm. Backpressure is a myth that people just keep believing. 😔😔😔

[@trevorseals6588]

Summit, I have a degree in automotive high performance and I know this is not how exhaust flow works, the story is about velocity. There is a specific formula for how big and long each tube needs to be in your exhaust system, this has to do with pressure waves and flow. The idea is to have a vacuum in your exhaust not pressure, pro stock dragsters actually have a measurable vacuum at the exhaust port and pressure at the intake port that equals around 7psi of “boost” combined on a naturally aspirated engine!!! This is due to the inertia of air.

[@rhynodon1843]

On an engine that produces 220hp would u recommend 2.5 or 3" single piping??

[@neilduncan8657]

What is also important is scavenging of exhaust correct exhaust sizing will help "pull out" the exhaust pulses from the other cylinders (my explanation sucks) to big or dual exhaust in some cases reduces this effect some vehicles do better with a 3" single vs two 2.5" duals

[@kelly1870]

If back pressure helped in ANY type of way then NASCAR would run it, pro stock, top fuel or any other racing would all use some sort of back pressure... But they don't... Scavenging is different and it has to do with pressure pulses working together to produce a small vacuum, not "back pressure". That's it. End of story. Point blank.

[@jackbitter9613]

Johnny SIX4 !! At least someone is informed, there is so much misinformation in the industry because of videos and "internet experts" like these

[@TheYoungerSemiOldMan]

Johnny SIX4 !! Very simple. You have street applications and race. With racing you spend most of your time at high RPMs therefore the flow will be greater thus requiring less back pressure. Im street applications, since the RPMs will be lower most of the time, you need it so the scavenging effect takes place. Otherwise you'll have no torque on the low end and only extra horses on the top end like race cars. As a result you lose low end torque and ability to pull through the lower gears and RPMs. Let's not mention fuel economy loss. You NEED back pressure to create the scavenging effect more so in trucks. It's a large vehicle that requires torque to get the large body moving, not horsepower. Horsepower takes effect at the upper end of the spectrum where torque isn't required as much. Mustangs are light and have high output motors. Stop and go traffic will destroy your fuel economy BUT with a free flowing exhaust, your horses will be higher so in race applications where you're at almost redline, you'll notice the benefits. I don't know very many people that spend that much time at high RPMs while driving to work, so it's not the most economical. You choose how you want your pocket book to go. Poor fuel until you hit redline or decent fuel the way the car was designed and sacrifice the upper end. Take your pick, you can't get both. How that answers your questions and clears your confusion....

[@JoeIsCrazyWillman]

Sofa King , NO, NOT BACKPRESSURE, YOU OAF! VELOCITY, AND ONLY VELOCITY. You're wrong because while backpressure will create velocity, it comes with parasitic pumping losses that are created bc the exhaust isn't working good enough, so the engine has to FORCE the exhaust out, hence pumping losses, but at least the pressure creates velocity. If you use proper size pipes, use mandrel bends, a proper balance pipe for dual exhausts, as few of bends as possible, as gradual of bends as possible, and as short of a system as possible (except doing open headers on a stock or mild build). Those will keep your velocity high AND cut backpressure too. You don't need one to have the other! You just need to get the right stuff! Geez

[@s.v.gadder1443]

Back pressure doesn't create the scavaging effect the fucking sonic wave does its a fucking harmonics thing not back pressure smfh

[@SirCavemaninthewest]

My hero.

[@dcarden3031]

if you have 500 horsepower to the wheels and had a single exhaust period you most have a sleeper on purpose.

[@VinzentDk]

I'm sorry guys, but your theory on back pressure is wrong here. On the board you are holding up at 2:12, the cylinder is at the intake stroke, i.e. the piston is moving downwards. If we assume that both intake and exhaust are infinitely big and have no flow resistance, then the pressure in the cylinder MUST be lower than in both the intake and exhaust. Air will therefore flow from outside through the intake into the cylinder, and exhaust would flow from the exhaust back into the cylinder. Air would not flow straight through the cylinder and out the exhaust port. This is a common misconception though, that stems from people confusing back pressure with gas flow velocity. The reason you don't want too big exhaust pipes is that you will reduce gas flow velocity, thereby not gaining adequate scavenging of your combustion chamber. Back pressure in an exhaust system is never desirable, since you would then use energy from the engine to push the exhaust gasses through the exhaust system. Google it, plenty of info out there on the subject :)

[@andre1980ytube]

Summit Racing , could you respond to the above comment? I also think that air would move from the exhaust into cylinder rather than outwards from cylinder during the downstroke. I do think back pressure is important ( as I have experienced performance degradation when I had an exhaust leak) however, I'm not sure if you have provided the correct reason for its importance in your video. Thanks!

[@Ron-jf1xz]

Vinzent Dk I absolutely agree, Vinzent. This demonstration is way off. During the intake stroke, the cylinder is going down and creating a vacuum to suck in the fuel/air mixture. There is no way that exhaust gas can also be flowing out during the same cycle. Al is correct that the exhaust valve stays open during intake but this is to 'artificially' increase the horsepower and efficiency. Here's how: - - - Allowing some exhaust to flow back into the cylinder increases the volume inside the cylinder without increasing the fuel/air mixture. This increases the pressure at ignition which makes the fuel more explosive and you get maximum efficiency out of the fuel. (Yes, it takes more power to create more compression, but the increase in explosion is well worth it.) If there is no back-pressure, you get less pressure inside the cylinder at ignition. This creates a longer, less efficient burn, and (because the exhaust valve opens during the tail-end of the ignition stroke), you could get burnt exhaust valves. This only applies to stock setups. If you're running a turbo, who cares. If you're racing, who cares, but if it's a daily driver, messing with back-pressure is going to cost you. IMHO

[@177SCmaro]

Ron "There is no way that exhaust gas can also be flowing out during the same cycle. " Actually, there is, but only during the end of the exhaust stroke or cycle and beginning of intake stroke. It has to do with the momentum of the gases durring overlap, when both valves are open there is exhust flowing out and air flowing in, the tail end of the exhaust flowing out helps draw in fresh air (scavenging) by helping to create a low pressure area on top of the piston. Exhaust flowing back into the cylinder (exhaust reversion) is actully a bad thing as it deludtes the fresh intake charge (this is what EGR do to lower combustion temperatures and reduce NOx emissions, dump a measured about of exhaust back into the intake). This is part of the reason cars with "big cams" idle so crazy. The late closing of the exhaust valve at low rpm lets exhaust back into the cylinder to mix with the fresh air charge which results in erratic combustion (sounds cool though). This clears up at higher engines speeds as there is less time for the exhaust to be drawn back into the cylinder.

[@dublaksheepdbs4873]

So what would you suggest for a 280hp car? suggestion for single and dual please. I have a 350z with just injen short ram intake.

[@JoeIsCrazyWillman]

Enrique Montero 3" single, and for dual, either a true dual 2.25 or 2.5 will work. This video was one whole pipe size off on his duals. He gave sizes for catback, not true dual. A true dual 2.25 can handle up to 400, so it's great for getting torque out of your motor. If you're mostly after the gains in the upper half of your rpm range, then go for the 2.5". It'll even sound a bitter burlier too, tho trust me, 2.25 can sound mean AF when done right (check out my vids and tell me how NOT redneck my truck sounds even tho it's a stock cam & everything). 2.5 will also leave you more.room to grow if you realistically plan on going above 400 horsepower. Otherwise personally I would go with 2.25, but 2.5 will also work fine if you want. Your choice.

[@axlegrind4212]

the atmospheric air pressure is 14.7 psi at sea level. what he was trying to explain with the cup, water, and cardboard is you have 14.7psi atmospheric air pressure looking at your tailpipe and if it is too big and not enough adequate flow pressure to overcome it, the 14.7psi aap *causes* back pressure on the exhaust. if the exhaust flow is lazy, it has to fight the atmosphere to come out.

[@gorillacookies3451]

Back pressure in the exaust system require's the engine to work harder period. Back pressure kills efficiency and performance , no ifs and's or butts. What increases efficiency and performance in a exhaust system is Exhaust gas velocity. And thats where pipe size comes into play. To big of pipe reduces the scavenging effect of the exhaust system by decreasing velocity. To small creates back pressure slowing velocity. So a correctly sized exhaust system with a correctly located crossover or X pipe is what most important on a street driven vehicle. Race tracks......less means more. So open headers are king

[@davidganster2218]

That’s it. I am officially moving to jegs.

[@AIR_RAM_PERF]

No engine needs back pressure! Its all about exhaust flow and velocity within the system. Go to small in ID and gain back pressure, go to large and lose velocity. The perfect exhaust would be sized to eliminate any "Back-pressure" and maximize velocity. Back pressure is exactly what it implies, its a restriction! Velocity on the other hand is what creates the scavenging effect from the cylinder. Every NA cam is designed with an overlap. The overlap is a small duration built into the cam where the exhaust valve is closing and the intake valve is opening, for a short duration both are open at the same time. An exhaust system that promotes velocity will have high vacuum on the exhaust side which literally tugs at the intake side giving the intake a running charge into the cylinder just as the exhaust valve snaps shut. This is called the "Scavenging" effect and most all cams are intentionally built with this overlap in order to take advantage of the scavenging effect. The quickest way to kill the Scavenging effect is to add back pressure! Long story short... dont believe everything you hear on the internet... like the video above, you are bound to be mis informed by people who claim to know what they are talking about... So dont take my word... get informed with the theory of operation and become a better Hot Rodder!!!

[@daveyelmer3222]

better. I still got no clear size formula. I calculus required ? That's ok.

[@yamahamer89]

You need Velocity not back pressure. Too big gets rid of Velocity.

[@cw6371]

Velocity is created BY back pressure. The more pressure you have, the more velocity you have. It's basic fluid dynamics. The less back pressure the better. If an engine actually makes more power with increased back pressure, something is fucked up.

[@utahcountypicazospage5412]

this guy has no idea what he is talking about vacuum is not back pressure I'm going to have to start my own channel

[@axiilll]

great video cleared up myths about back pressure

[@DanneyTanner]

Pipes seems a little big for the hp.Is it true you can run a smaller tail pipe and be ok?

[@SummitRacing]

It works best when the whole system is the same size. Here is a link to an exhaust size calculator. www.exhaustvideos.com/faq/how-to-calculate-muffler-size-pipe-diameter/

[@davidsnydersr160]

Old school had it that a certain amount of back pressure was needed to help transfer heat from the exhaust valves? And if not then why use any exhaust? Maybe along the lines of the thermostat concept?

[@Emvy11]

1:05 mind blown

[@detailinggaragekilkenny591]

1.3 65hp? 2inch single be okay?

[@SummitRacing]

Yes, that would be plenty large enough for the 65hp 1.3L engine.

[@detailinggaragekilkenny591]

@@SummitRacing that's for reply , it's classic carbureted 4 cylinder

[@bobmigarski283]

a good rule of thumb i use is take the amount of liter and divide by two eg 5.0l=2.5 in pipe 6.0=3 inch pipe of course it doesnt take in to account power but it gets close enough

[@daveyelmer3222]

Metric or english: pick one, preferably the old English system in the USA.

[@oscarantonio6795]

For me the back pressure is very important in a 2 stroke engine but not in a 4 strokes where the main think is the speed of exaust gases.

[@hexatonik]

actually, the water stays in the cup because there's a vacuum formed when you turn it upside down and the air can't expand enough to let the card off the rim of the cup, has nothing to do with back pressure lol

[@hamdanalharbi2206]

+PC Pro vacuum is negative pressure which is lower than the atmospheric pressure ... therefore the atmosphere pressure is the force that keeping for you information pressure is force divide by area. area is constant for the cup for both sides. the pressure in the cup is lower than the atmospheric pressure which mean the force that holding the card to the cup is the atmospheric force!

[@hexatonik]

+Hamdan Alharbi regardless, it has nothing to do with back pressure which was my original point and you just proved that yourself so thx :)

[@curtisdodds493]

Sounds good, but you're wrong. The force in the cup is actually greater than the atmospheric pressure which really has nothing to do with the card staying up. The suction of the vacuum inside the cup exceeds the gravitational force being exerted on it.

[@hexatonik]

+Curtis Dodds that's basically the same thing I said, its because of the vacuum not because of back pressure.

[@curtisdodds493]

+Curtis Dodds I was responding to hamdan alharbi

[@brandonnlynn2464]

Where can i buy 8" exhaust pipe? I need a 6" piece for my VW Vanagon.

[@ThatGuy-sd3zl]

Home Depot.

[@grimeyhonkyracing3938]

HVAC supply get some chimney pipe

[@CJ-ty8sv]

Sorry, but this video is an absolute joke!!!!!! You want back pressure because of the valve overlap?????? Thats 100% absolutely false. Combining back back pressure with valve overlap will reduce power which the last time I checked, it the primary reason why most people what to change their exhaust is to increase power. I'm quite disappointed that Summit Racing and the Company that they are would even put out this video. To anyone why believes that you want even any backpressure, I suggest that you educate yourself on what exhaust scavenging is and how it effects cylinder filling and why we attempt to design exhaust systems and headers to have maximum scavenging (particularly in the region where the cam(s) create the most power) ...

[@Moparmaga-1]

Question for you, is there any benefit of additional collector length in a 480-520 hp street car ?

[@cw6371]

@@Moparmaga-1 only if the collectors are open to atmosphere, which is not practical on a street car.

[@Moparmaga-1]

@@cw6371 okay thanks.

[@jefke12321]

the sience experiment worked. theorie behind it didnt.

[@derrickterrell4217]

Awesome explanation of back pressure in the kids experiment.

[@harwin.ignacio]

I have a motorbike with 16 hp and i want to know what exhaust should i use because i can't find any table for small bikes

[@TheBimmerfan]

Best explanation of the need of some back pressure in exhaust systems I've ever found. Great video, thanks.

[@SummitRacing]

+TheBimmerfan, Thank you for watching!

[@redbaron77]

The chart is great. The guys theory is wrong. It's all about flow rate. The faster you can force air in and out the more power. Meaning to small pipe will choke it out, to big and your engine wont be able to push all the air that's in that pipe out slowing velocity. The perfect size will help power at all rpm ranges. To big you'll loose torque to small you'll loose top end horsepower. That's where I'm at. My truck made 225 hp and ford decided a good size pipe is 2 1/4 SINGLE exhaust. I changed it to 2 1/2 but now I'm making a little more and it definitely feels choked up after 3k rpm. Engine is a 302 btw.

[@noroadblocks2000]

Free flow or straight pipe , which one is better

[@mariovalentin8057]

I got a 2.25 exhaust pipe and I just installed a 2 inch inlet/outlet Magnaflow turbo muffler...Is that going to slow my car?...Or it doesn't really matters?...Thanks in advance for your help

[@toyotabrony]

@SummitRacing I own a 2015 lifted Scion xB. And since i only have a TRD sport muffler and a 23” length cherry bomb glasspack. The inlets are weld between 2.5” and factory are 2”. It creates a nice mature exhaust note. Now I am planning to get a full custom exhaust 2.5”. With 2.5” magnaflow high flow cat, and a 2.5” vibrant ultra quiet resonator. This will give much deeper tone and better performance, and also better breather correct? Along with headers included since why I am gettin a high flow cat. No sport muffler from axle back bytheway. So instead of sport muffler axle back, to glasspack, to factory cat. Switch to no muffler on axle back, the vibrant ultra quiet resonator, and high flow cat.

[@bobbyshreve8178]

I have a 496 ci chevy i want to build a custom exaust do you have every thing i need im wanting to go out the back side by side about 8 in apart i have a fuel cell

[@jstanden2589]

What if your in between 300 and 350 hp

[@svenp6504]

Hahah, you noticed that too.

[@JakeMerritt1992]

3.75", duh

[@jstanden2589]

+Jake Merritt Haha

[@PawlDunken]

I'm more then 350 I'm 380

[@julianoliva2850]

Right now designed and put in a custom header 4-1 with high flow cat, 2.5” pipe and a 19” oval Borla proXS Into a 2011 Chevy colorado 2.9L stock engine with some upgrades Do i make ok?

[@ProjectCarTV]

This guy throws a hotdog down a hallway.

[@oscarcervantes610]

I installed a flowmaster 40 series and dumped a 3" pipe right after the flow master eliminating the original pipe....now I feel that I lost power should I install the original pipe to get my back presure back?

[@SummitRacing]

+Oscar Cervantes, Yes, by adding the 40 series and removing the tailpipe, you’ve freed up flow so much that you have leaned out the motor to the point you’ve noticed a power loss. You could also try having the computer flashed with a new program that adds a little more fuel.

[@emilioemilio8713]

+Summit Racing i have 60mm exhaust catback on my 4 cylinder and it noticeably slower at HIGH RPM what causes it?

[@Josh-py2in]

It's very simple. Let's say you have a Honda. You run a 3" straight pipe with no cat or muffler, you will move all of your power up high and loose all of your low end power. If you ran 2.25" and have a muffler and cat, you will loose high rpm power and gain low and mid-range power. You want to match your cars exhaust system with the build of your specific engine. If you run a huge camshaft and close ratio gears, you want high rpm HP and huge exhaust. If you have a low duration camshaft and tall gear ratios and a tow hitch, you want more torque. So buy the minimal size needed for your engines hp. I've built many cars, and there are some exceptions to this such as turbo cars. And this guy's numbers are way off. I made 550 hp on a GTI with only 3" single pipe exhaust. My station wagon makes 365hp on 2.25" exhaust. Just remember, exhaust does NOT create HP, the engine creates it and the exhaust supports it and moves the power around.

[@kyorix_SDF]

Hi, any advise for me please? I do have a Tiguan Mk1 2.0TSI , I plan to make it around 300hp. Which size of exhaust system is recommended, I do think of 3"?

[@Josh-py2in]

@@kyorix_SDF the stock exhaust is 2.25" and more than enough to support 300hp. Being a turbod car, I would recommend removing the catalytic converter and get a high flow downpipe. When you do this, you will need a tune to get rid of the check engine light. With just a downpipe and ecu tune, you can make about 255-275hp and 325-350tq on your engine depending on the tune you choose and fuel quality. 300hp would require a bigger turbo such as a Borg Warner K04-064. That turbo is capable of making 350-380hp with a proper tune, high flow downpipe, and bigger intercooler.

[@kyorix_SDF]

@@Josh-py2in Thanks for the advise, I am currently studying on crucial parts as well which including K04 you have mentioned. I was wandering if F23t is better. Intercooler and the rest of supporting stuffs are much easier to choose. I currently have a stable aftermarket suspension system.

[@Josh-py2in]

@@kyorix_SDF the f23t is a essentially a modified k04. I have ran both, and the f23t can make 400hp and 400tq with an agressive tune and high octane fuel. There are a problems with the f23t though. They tend to over boost and surge. This is due to the small housing and upgraded wheel. This makes tuning a giant pain in the ass. You will likely need a custom Dyno tune to make it run properly. Also, they're not as reliable as a k04-064. Both turbos will usually cause a problem will valve float at 5000 rpms and above. This is because they have small housings and are being pushed way past their efficiency range. This will cause excessive back pressure and push the valves open at high rpms. The fix for this is expensive as it requires upgraded valve springs. My advice is a k04-064 and an APR tune. They have a new revised tune that will avoid the valve float at high rpms by lowering boost and raising ignition timing above 5500rpms. You should have no problems making over 300hp with that setup. Also, if you want big power and no issues with valve float. Look at the gtx2871r TSI kit. It runs about the same price and will make well over 400 and have no valve float issues. This turbo would require a 3" exhaust to make good power

[@kyorix_SDF]

@@Josh-py2in I see, should I upgrade my pistons then? I am worried if they can sustain the 400hp

[@boosted2.4_sky]

I have a 2.5" Borla single exhaust and it's sufficient to ~350 hp. Not sure where that"chart" or "rule" came from...

[@gorwinchee9767]

v rod muscle 1250cc, how to choose a good exhaust, long or short

[@kervz12345]

Heool I have a 3inch downpipe reduced to a 2.5inch decat and a 2inch custom r32 rep exhaust system will that be on ?? I have a mk4 golf 1.8t pushing just under 200bhp ??

[@Buchoass]

Hi, I own a 1994 Dodge Ram Cummins Turbo Diesel. The garage just welded a smaller exhaust pipe and muffler into the existing pipe.. Total hack. What will this do to my truck? Thanks.

[@christophercastellanos4455]

What about 100 hp?

[@thomaslimont9904]

What exhaust should i get for a 04 marquis with a 3in Muffler

[@kvnglee8739]

my car has 300hp to the crank..its a DOHC 4.3L v8…my exhaust system is 2.25” and i was wanting to run a 3” with an xpipe from my cats with a 2.25-3” adapter…is that safe or ok?

[@healey5537]

I have a true dual exhaust v8 with 360whp, stock is 2.25 for a cat back dual h-pipe exhaust should I stick with 2.25 or go with 2.5?

[@coltscurlock509]

Could be vacuum effect on ur lil cup of water trick???

[@Hillary4Prison]

4.5 inch cork screw pipes.. because i can. It scrapes in a few places but the back pressure is perfect!

[@stevengonzalez25]

dual exhaust vs single ? which is better for performance gains?

[@utahcountypicazospage5412]

Steven Gonzalez top end dual no doubt and remember mandrel bent is more expensive but is the true size unlike crushed

[@lightworker28]

Can i install a 2.5 muffler on a 2.25 exhaust system?

[@wa7eeedinAus]

Hi, I appreciate your help. I just did and ECU tune to my bi-turbo car and now its putting around 530hp, I have added a sport filter and now I'm planning to replace the stock downpipes. What diameter should the new catless downpipes be? Thanks *edit* and its a dual exhaust system.

[@SummitRacing]

Mo Al , We need some additional information from you. Can you give our tech department a call? 1-330-630-0240. Thanks!

[@Domas64]

Let's say headers are correctly selected, but muffler is causing the backpressure. If bigger muffler is used, with bigger exit port, will it reduce backpressure, but keep the muffling effect the same?

[@SummitRacing]

+Domas64 , Yes, even though you’ve opened up the outlet, when you increase the case size, you will still be able to control the sound level well.

[@fernandogonzalez4365]

Does it matter if its is turbo or supercharged??? What about high altitud country?

[@reybarajas6878]

I have a quick question I'm working on putting my truck back on the road I drove it yesterday and it Boggs out when I give it half throttle but if I ease in the accelerator it picks up just fine could it be because I'm running open headers

[@SummitRacing]

Hi Ray, We need some additional information from you. Can you please call our tech line? 1-330-630-0240. We look forward to your call. Thanks for watching!

[@perjian1697]

sounds like your accelerator pump isn't working properly. could also be ignition timing. I'd rule those 2 things out first before troubleshooting other areas.

[@williamhocking598]

I’m installing on my 02 540i E39 BMW a Borla exhaust from axle back, Im told it came off a bmw I can tell you it wasn’t a E39 and possibly not a 540 but it sounds so good !!that’s why I’m hell bent on installing it. But it’s dual exhaust and there’s no room on the rear passenger side so I’m going to delete that side and go with the single exhaust but in order to do so I have to increase the pipe diameter to 3 1/2 “ diameter for a 282 horsepower car (+nitrous add 100 more) do those figures sound right ? I’ll need 3 1/2 “ diameter ? Where can I get 3 1/2 diameter pipe and have it mandrel bent ? And do I go all the way to the exhaust tips

[@trentyncramer4530]

Question: I have a 2001 Sierra 1500hd I installed long tube headers x pipe 3inch exhaust. No cats. I definitely lost power is this because I have not enough or no back pressure? Or does it just need tuned? I’d assume both it definitely got an increase on the high end of things but on the low it’s much slower and according to my scanner I lost torque.

[@tylerburtch3234]

What if there is a turbo?

[@Riverside_Lawns_n_Garden]

I have a stock 2004 Tundra 4.7 V8. I spend a lot of time off road and wanted to add some sound plus some more torque. My idea was a x pipe after the cats, dual mufflers and then step down to 2 inch tailpipes dumped right above the rear axles with turn downs. I wanna keep it high up and stop it just after the axles for clearance. How would that affect backpressure going from stock single with 2.25 to duals at 2 inch?

[@Connor4x4]

I have a 1999 F150, 4.2 V6. I am keeping the resonator's and catalytic converter's as well as stock exhaust pipes. I am looking to replace my worn out stock muffler and I like the sound of the thrush glasspack. I am just wondering if the straight through design will damage my motor. I use it for towing and I don't wan't to lose low end torque.

[@SummitRacing]

+GREATSWORD1000 , By keeping the factory pipe size and converters and simply changing out the muffler, no torque loss or engine damage will occur.

[@Connor4x4]

Thank you very much!!

[@AtobaLongkumer]

Which size of exhaust pipe should I go for my Willys F-134 Hurricane engine to get maximum performance out of it? Should I also keep the muffler in place or should I remove it?

[@SummitRacing]

+Ato Lkr , There is no reason that a 2” pipe won’t do just fine here. Unless you’ve done some mods such a s a cam and intake, in which case a 2.25” upsize would work good! As far as a muffler is concerned, how loud do you want it to be?!

[@AtobaLongkumer]

+Summit Racing Thank you for the reply. I want the sound sound real loud enough but not too extreme. What are the intake modifications that I can look for?

[@javontewashington9141]

1 have a 2003 ford f250 5.4 2v and i have shorty headers for it and want to h pipe it but dont know what size piping to use im trying to get all the low end and mid range hp and tq i can cause i haul cars can u help me out

[@CamaroWarrior]

i have a 1999 Camaro SS and its all stock, and thinking of removing my resonator only, because i want it a bit louder, will it effect my gas mileage or back pressure by removing it or effect my car in anyway besides the sound being louder?

[@SummitRacing]

CamaroWarrior , You should consider a new tune for the computer!

[@stihigh4848]

Thanks for the video. Would you please clarify something for me. At 3:30 you say "From 250 - 350 HP" but the video text shows "250 - 300 HP"? Should the video text have shown "250 - 350 HP"?

[@andyearls1896]

i have a 5.3 engine. i want to ran a straight pipe without a muffler but i want to keep the same amount of backpressure when the muffler was there. how do i do that?

[@SummitRacing]

Hi Andy Earls, We need some additional information from you. Can you give our tech line a call? 1-330-630-0240. We look forward to your call. Thanks for watching!

[@sanskaribachee6423]

how would i calculate the primary pipe length , diameter, also same for muffler design?? any calculation that required?? i have read many sites about it but no one have answer that suit my conditions. plz help

[@VR46champion]

Okay somebody answer me. Removing the exhaust resonator. Will this affect performance? I have a 2.25" custom catback with a perforated 12" resonator. Removing it will it reduce performance or all about being louder?

[@patrickrechichi7406]

Mark not by a large amount as the resonator is there for mainly dampening out sound.

[@JoeIsCrazyWillman]

Mark No real change in performance. basically it's kind of like a glasspack. Dampens and controls sound a little bit, but doesn't really change flow. basically a straight pipe inside. You'll make your exhaust louder and a little higher pitched taking it off.

[@mithunmenon9559]

I have an enfield classic 500 efi which has an upswept silencer which was recommended by RE. Now i am planning to change ghe silencer so tht i could get that old royal thump.( new engines r refined and lacks that old cast iron thump). So if i try to increase the thump using a wildboar or megafone silencer will it affect the engine.it surely will increase the backpressure right.

[@JonoLam]

I have a 2003 corolla hatch with 2" exhaust and I want to do a muffler delete would I just weld on a straight pipe with 2" diameter after the CAT? and what pros and cons will I get since I just want the raw sound?

[@mithunmenon9559]

Wait a min.so u mean the ehaust valves are made in such a way that it only opens in one direction ( ie towards the exhaust pipe) so that the back pressure helps in closing these valves dring induction stroke?

[@SummitRacing]

Hi Mithun Menon, Can you give our tech department a call? 1-330-630-0240. We need some additional information from you. We look forward to your call. Thanks for watching!

[@D3AThCAl2DS]

back pressure you mean bad flowing exhaust ports?

[@1000186ful]

What about going from say a 3inch header down to 2.5 inch muffler would there be a problem?

[@SummitRacing]

Yes, you can reduce to a smaller exhaust tubing, as long as it is appropriately sized for the engine size and power output of the engine. For more information or help choosing the correct exhaust for your headers we would recommend speaking with one of our sales agents at 1-800-230-3030.

[@The44One]

I have a 2017 Dodge Ram v6, I took off my stock muffler and put on a after market muffler I didn't like the sound so I put back the original stock muffler. My question is can I lose torque cause I took off the pipe and put it back to it original ??

[@JoeIsCrazyWillman]

Mike Vasquez Very minor difference if that's all you did. Only like maybe 7lbs of torque. Not noticable.

[@jordanp6420]

If I have a standard 2.0 L 4 cyl engine with no modifications whatsoever and i put on a cat back exhaust for example for a nicer note. And let's say it lets the exhaust flow too freely for my engine power and I have too little back pressure, what problems will this cause. Should I still purchase this exhaust?

[@fredocantoo]

I have a V6 challenger that’s puts out about 315 to the crank would it benefit me to get a 3inch

[@SummitRacing]

Hi Freddy, we are assuming you have a 2.5 inch now, therefor a 3 inch wouldn't hurt anything.

[@ProfJr-id7ln]

i think that all the things that you mentioned in the video are the inlets size right? how about the exhaust tip outlet,can you tell us specifically,what sizes are the best for which? so that we don't get confused on choosing sport exhaust muffler which has their inlet and outlet sizes..

[@ProfJr-id7ln]

+Hhmut OneSevenEight hello?

[@SummitRacing]

+Hhmut OneSevenEight , In the industry, exhaust piping is measured on the outside while mufflers are measured on the inside. As for the tip outlet, tips are considered a decorative piece for the most part and can be the size you choose or are limited too by bumpers or body work. Obviously you wouldn’t want a smaller opening on your tip so as not to create more back pressure.

[@ProfJr-id7ln]

wonderful answer. i have 2" of exhaust piping. so,I am going to put 2" inlet and 3.5" outlet muffler.. so,i think that that will not create back pressure right?

[@carlodioso495]

Is it okay to have bigger outlet from muffler but still have right diameter on inlet for engine HP?

[@hnkfsh81]

Engine Masters has debunked the backpressure myth.

[@brandonflynn8621]

I have a bmw e90 328i and was wondering if I did a muffler delete and put in a 3" pipe extension and put back the stock tips would there still be enough back pressure to ensure decent mpg

[@SummitRacing]

Hi Brandon, When increasing airflow through a computer controlled engine such as yours, its best to have a new tune done at a local dyno shop to ensure best all around performance! In some cases you can find a computer programmer for many vehicles, but make sure other modifications are taken into consideration by that vendor for best results!

[@Stinkhole101]

hi there, I have a golf mk4 1.6 and It has a mid box and a large muffler at the back. now if I take the mid box out will the backpressure be to low for the car to run properly without any damage towards the engine?

[@SummitRacing]

Hi Marc, No way to guarantee no damage but, you will need to re-flash the computer due to the increased airflow into the motor and the potential of a lean condition occurring!

[@egSmith-sp9gl]

Your funny !!!!! the mass air flow will detect the amount of air entering the engine and the computer will adjust everything !!!!! You don't know much about modern fuel injection I gess !!!!!! Bosch injection system can learn !!!! and for the back pressure your all wrong too lol ........

[@marscetier101]

+e.g. Smith well I know enough but at the same time I've heard it'll hurt the motor more than you think by wearing valves etc , but I've got to an exhaust shot and they to say that there won't be enough back pressure. Remember it's a 1.6 8valve (NON TURBO)

[@egSmith-sp9gl]

You've heard !!!!!! If he remove the middle box he still have the cat and the muffler !!!! What you heard is a mith same as the engine need back pressure

[@sbclt1chevy184]

Okay this is my situation I did a 5.3ls swap into my 3rd gen camaro and I have 1 thrush glass pack but I want some back pressure and not have my engine be so loud but I still want the glass pack sound could i install some type of exhaust before my glass pack?thank you

[@SummitRacing]

Hi SbcLT1 Chevy, Any muffler, resonator or catalytic converter you add before your glasspack will change your current sound because you are adding restriction!

[@sbclt1chevy184]

+Summit Racing Oh okay I don't have a catalytic converter on it my home state doesn't require one but am thinking on a high flow catalytic ill give summit a call thanks :)

[@BIGMOE87]

well....... i have a 2009 Toyota Sequoia stock headers deleted 4 cats & replaced it with 2 same factory size pips directly fixed to ( 2.5" ) 2 X enter TO ( 3" ) single exit Borla pro XS muffler am i doing it right or theres another good idea to gain more HP's ??

[@josefigueroa2150]

i have a 02 accord v6 sedan dual exhuast.but is after maket.i think i lost power do to no back pressure is it true?can i make it single?if yes do i put a muffler for back pressure?

[@anonymoushonest3611]

Great information and thanks for sharing with us. My question is that I have a 1998 Lincoln town car and it is the time for the car to get little upgrade. I ordered a 3 inch inlet/outlet 16 inch length resonator and when talked to the specialist about the diameter of the pipe, he recommended 2.5 inch pipe. Unfortunately I can not return the resonator, but I ordered 2.5 inch inlet/outlet muffler and waiting for it to arrive. My question is about the resonator. Can a resonator be bigger in diameter for my car and is 2.5 inch pipe ideal for my car? I hope I could make some sense with my question. Thanks

[@athalfridhu]

How can a narrow X pipe affect the diameter requiremets for a dual exhaust system???

[@SummitRacing]

Hi athalfridhu, Can you give us a specific example?

[@timothyblaze4556]

I have a big big big question, I'm wondering if you guys could please help me out. I have a 2015 dodge ram 1500 Hemi. I had a muffler shop cut ONLY my muffler off. The stock exhaust is a 3inch pipe all the way to a Y-pipe towards the rear of the truck and then goes 2.25 from there to each side. But the exhaust shop added about a 3ft section of 2inch exhaust pipe BEFORE the aftermarket y pipe then to the Y and out to the two pipes. So what I'm asking is where they added that 3 ft section of 2 inch right into the 3 inch pipe BEFORE the split at the Y will that hurt anything? They said no (The muffler shop) but I wanna see what you guys say. They connected the 2 inch right into the 3 inch welded it and said it's fine. Please let me know thank you guys!!!

[@Loneshark907]

What’s your guys best guess for a 95 f150 with a 302 5.0 V8

[@Clorox__Bleach.]

I want to leave the cat and pipe on but i want to take my muffler off i have a 4.3 v6. Will removing my muffler hurt my engine?

[@SummitRacing]

*****, It will increase airflow through the motor potentially leaning the motor out. Too lean will cause combustion chamber temperatures to rise and spark knock. The answer is to increase jet size if carbureted or re-tune the computer programming if injected.

[@rogerhernandez5193]

guys I have 2013 f150 4x4 5.0/ ive been wanting to have a dual exhaust installed with a muffler on each pipe strait back instead of going to one then back out into a dual but a guy told me that it would turn on the check engine light. but he did mention I could remove the resonator to give it more sound and that it would be best to have just one muffler then back out into dual. and I was thinking of a flowmaster any advise I'm new to this truck thanks.....

[@metribblet]

I have 2 inch pipes on my car. I'm buying new mufflers that only come in 2.25 and 2.5 inches in diameter. Which is best to get if I don't want to purchase an entire exhaust system? Is there any way I can accommodate the difference in size? Please help. Thanks

[@SummitRacing]

Malik Tribblet , We carry reducers that will allow you to use the 2.25” mufflers. Give us a call and we can help you pick them out. 1-330-630-0240. Thanks for watching!

[@bobby9642]

What if for 1.5 cc car ? More than 2 inch for that engine is really big

[@PrabodhaRandima]

How does the back pressure effect to the performance of the engine and how does it effect to the fuel consumption of the engine??

[@SummitRacing]

+Prabodha Wijerathne , The cause of backpressure is trying to use an exhaust pipe size that causes restriction to escaping exhaust gases. This does not allow the engine the breathe well reducing power and sometimes fuel efficiency. To improve the engines breathing ability it is popular to increase pipe size but, be careful not to go too large giving the gases too much area to expand and slow down flow! Bigger is not always better! The key to it is to find a pipe size that allows good flow while promoting scavenging. Depending on your combination of parts, this may take some experimentation.

[@irshadrizvi105]

I have Lancer 4g15 dohc, modified head, inlet and exhaust valve. What's the diameter size do u recommend for best performance

[@SummitRacing]

+Irshad Rizvi , Unless you have a realistic power estimate of your combination, it’s a stab in the dark!