Why Not to Put Exhaust Headers on Your Car

rev up your engines, today I’m going to
talk about why not to put exhaust headers on your car’s engine,
now exhaust headers serve one purpose they allow the gas that has burned
inside your engine to come out the exhaust and then flow through the
catalytic converter through the muffler and out the back and on the factory cars
they’re called exhaust manifold, not header, cuz cast-iron can take a lot of
heat it’s strong it’s not gonna break, plus they’re relatively easy and cheap
to manufacture the exhaust manifold is under this heat shield it keeps the heat
from getting in and damaging anything under the hood and the design of the pipes
are for one main thing to get the exhaust gas to leave as fast as possible,
so the engine can have as most power as it possibly can and to run the most
efficiently, now when I was a young mechanic all vehicles were carburetored
practically and if you wanted more power out of a car, you could change the stock
to fancy headers like the ones in the picture behind me and a fancy headers
would flow better they had better heat characteristics,
they could be custom-made for each engine to get more horsepower, and since
they were simple, carburetored engines all you had to do was re-jet the carburetors,
put jets that were the right size so the air fuel mixture would remain perfect
since you changed how the exhaust flows you have to change how the air intake
comes in to put fuel into the engine, now back then if you had a stock Chevy 350
v8 engine and you put racing headers on them that were tuned correctly, you could
get maybe about 16 more horsepower out of that big v8 engine, but you have to
realize that most of that horsepower gain was at the really high rpms their
made more for racing than street driving since the headers aren’t made out of
cast iron, a lot of times they were stainless steel, cast iron is thick
stainless steel is thin, so they can have wider openings for the exhaust gas
the cast iron would be restricted down because it’s thick where the stainless
steel could be wide open and they’d flow better,
so headers in and of themselves don’t give your engine extra horsepower, they
just allow your engine to get the most horsepower out of its design that it
possibly can, while all modern cars are all fuel injected
and if you put headers on them you have to do a lot of reprogramming, you have to
find a mechanic with a five gas analyzer and a dynamometer and is able to
reprogram the computer to make it run correctly for the new flow that it has,
and in the case of many modern cars if you’re driving them on the Street in the United
States the exhaust manifold has the catalytic converter built-in, so if you
remove the stock and put on these racing headers you’re eliminating a catalytic
converter, you’re breaking the law you can’t take a Catalytic converter off a
car, so putting fancy headers on a modern car that you’re driving on the street
it’s just not a very smart idea now I know people are gonna say, Scotty oh the
guys that are modding their cars they put headers on, but yes that’s generally the
last thing they do when they totally modify a car to either race or to get a
ton of horsepower out of it and often in places where they don’t even do state
emissions testing, so they don’t have to worry about having it passed an emission
test every year to be on the road, first they’ll rebuilt the entire engine to
make it stronger, then they’ll put either a turbocharger or supercharger on it,
then on top of that as the finale they’ll stick nice fancy headers on the
engine so it flows as well as it possibly can and it has the most power
that it possibly can, now I still see guys trying to do it on street vehicles
here in Houston and then you see them going down the street and they’re shifting
gears you can hear the engine backfiring and popping through the exhaust, it’s
cause they just bolted headers on they didn’t change anything else and the car
doesn’t run right it can actually cause the Pistons to hole from pre-ignition
because they won’t run right, and sure they look cool when they’re under the
hood, a lot of times they’ll have them all polished and shiny and some of the
guys will wrap the headers with heat tape so they retain the heat better and
then they flow out faster for more power and they’ll remove the catalytic converter
sometimes even the muffler and have a totally free-flowing exhaust, they like
that giant loud sound, which is fine on a racetrack but in most places it’s highly
illegal they put out too much noise the decibel level is too high there’s laws
for that most states, so they won’t pass inspection because they’re too noisy and
since the stock exhaust manifolds have heat shields on them and the fancy ones
don’t, you stick headers on modern engine you can make the engine
compartment get way too hot, it’ll mess with the electronics and all the
wiring of a modern car and since you generally driving on the
street, these modern engine designs their stock are designed for generally
stop-and-go city traffic where they do most of their driving, not going top-end
a 130-140 miles an hour, so putting headers on any modern engine
it’s a dumb thing to do for something you’re driving every day on the street,
so now you know why it’s a dumb idea to put fancy headers on a modern car that
you’re gonna drive every day, sure it’s certainly fine if you’re building a race
car, for driving on the street that’s just stupid these days, because you’re
not gonna gain that much horsepower for the relatively large amount of money
you’re gonna spend putting the headers on and then having the system reprogram
to accept them correctly, so if you never want to miss another one of my new car
repair videos, remember to ring that Bell!


  1. Scotty Kilmer October 12, 2018 at 1:32 pm

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  2. Ky'mani Ar'min September 15, 2019 at 12:38 pm

    I respect Scotty as a mechanic, but damn if imma pay for a car ,I'm gonna do wtf I want to my car and enjoy the ride. In my state theres no EMISSIONS TESTING. So rev up your engines 🔥😈😈

  3. Rat Rod Studios - DRR Customs Ltd September 15, 2019 at 12:41 pm

    Any modern ECU will slightly remap the fuel injection to compensate for the headers. That’s what the upstream o2 sensor is for. But if you’re a mechanic you would know that. There is no reprogramming needed. Not sure who told you that.

  4. hondurasallday123 September 15, 2019 at 7:59 pm

    Scotty for president 2020.

  5. Dadlegz September 16, 2019 at 1:37 am

    I always run a high flow cat when I mod a car, also heat wrap on the headers 🙂

  6. Damian Smith September 16, 2019 at 3:08 am

    I'm sure Scotty does know that LONG TUBE HEADERS come in different variants for street and racing and they also have HIGH FLOW CATS built into them which doesn't get rid of the CATS and still keeps you legal……

  7. Preston Graham September 18, 2019 at 12:18 am

    Cast is heavy , holds heat, and doesn't brake…. what cars has he been working on I've seen tons of cars with cast crack at night heat spots.

  8. Preston Graham September 18, 2019 at 12:24 am

    What planet does this guy live on? He says some normal common knowledge stuff but then says a few somewhat incorrect things based on assumptions. High end headers are pretuned from the manufacturer complement the factory ECU. Maybe some with the use if a basic data logger/reflash unit. There are other dumb things he says but I'm too lazy to keep going. Night bros.

  9. Chum Lee September 18, 2019 at 12:35 am

    how u gunna put headers on a car that already has a turbo

  10. Broke September 18, 2019 at 3:28 am

    I only put headers on my Toyota Cilica.

  11. Jeremiah Valeska September 18, 2019 at 4:06 pm

    John Lennon sounds like Rod Stewart

  12. Kobus Oelofse September 19, 2019 at 6:52 am

    My friend put headers on his chev spark 1.1 . While keeping everything else stock. Well he had too since the end of manifold was so rotted. Car sounds nice and grunty without the loud noises. My rav4 1995 Toyota is stock though, roll like that. The engine is so lame but the reliability that comes with it, just overshadows everything

  13. streetracing plug September 20, 2019 at 10:36 am

    I beg to differ it's a bad idea to have a header on a daily driver

  14. Chaotic Video September 20, 2019 at 9:41 pm

    This guy literally panders to his age demographics and that’s it.

  15. Cody Jackson September 21, 2019 at 3:55 am

    I think I'm tired of hearing your mouth !

  16. Logan Gamache September 22, 2019 at 8:36 pm

    Does he hate all engine mods, shut up my guy

  17. Ben Krom September 22, 2019 at 10:34 pm

    Sorry Scotty, but headers and exhaust manifolds are the same. TUNED headers are different than headers. I've put TUNED headers with performance catalytic and converters on, and reaped the rewards. Many misrepresent exhaust manifolds as TUNED headers. Not the same !

  18. Garry H September 24, 2019 at 1:22 am

    Scotty are we Aloud to have a motor..lol..headers and mod parts have been around since the 50s..
    And even now lol..99% of the people are happy at the perfromance they get..

  19. Garry H September 24, 2019 at 1:23 am

    Scotty wants you to have a 1 inch pipe……

  20. Garry H September 24, 2019 at 1:26 am

    Scotty you should just stick to cleaning up your garage..

  21. Jake The Snake September 24, 2019 at 2:20 pm

    You're like someone's dad who thinks everything is a waste of money.

  22. dustyak79 September 25, 2019 at 1:39 am

    Scotty Buzzkilmer "engineers designed these for a reason" Also Scotty those damn engineers what were they thinking. Engineers " we also design the after market parts"

  23. Mark Love September 25, 2019 at 5:21 pm

    Headers are the last part put on? 😂 no , headers are far more efficient , than a typical cast iron manifold. This whole video is full of bad information… I’d stick to being a parts changer if I were you

  24. Michelle Lopez September 26, 2019 at 7:43 pm

    Scotty's full of bull dump..he thinks he's the only one that can rev up his engine

  25. Garrett Chapman September 26, 2019 at 10:38 pm

    Scotty before you install a turbo, you have to install exhaust turbo manifolds first….lol

  26. zack attack September 28, 2019 at 4:31 am

    Scotty your such a downer

  27. M N September 29, 2019 at 12:37 am

    Why not to put gas in your car.
    It will make your car move
    It cost money
    It will move faster than his walker with tennis balls lol
    Oh yah so the sound wont make his hearing aid squeal

  28. Juju Dudon September 29, 2019 at 2:44 am

    Smh glad I never subscribed to your channel. Scotty you getting old my guy just retire already DONT REV UP YOUR ENGINES lol it’ll catch your car on fire

  29. None yo Business September 29, 2019 at 1:55 pm

    Hypocritical of state laws they go after cars for being loud yet motorcycles are way louder

  30. Miller Goon September 29, 2019 at 10:43 pm

    Very very smart answer makes me think twice now 💯❤️😁 thank you Scotty 👍🏾

  31. Stefano Varela-Baez September 29, 2019 at 11:01 pm

    Oh god not high a flowing exhaust

  32. GabrielKish September 30, 2019 at 12:13 am

    Ive installed long tube headers on every car I've owned (except my Jags as no one makes em) and they dramatically increased the power. Rarely are stock manifolds more than an afterthought on engines. There are exceptions but most factory manifolds just SUCK!

  33. Duwayne zl1 September 30, 2019 at 6:42 pm

    He says more power and flow better

  34. Eric Schlegel October 1, 2019 at 1:45 am

    Your hands are too clean for you to be giving me a “why not do this to your vehicle” video.

  35. The Stupid One October 1, 2019 at 2:26 am

    You can remotely tune most vehicles with EFI now, just buy the parts a tuner has experience with on their platform and they'll upload their tune into your vehicles ECU. Not that difficult Scotty.

  36. Luke Blaikie October 1, 2019 at 10:25 am

    Sooooo you put a turbo on , then headers … ime confused

  37. jaakko200987654321 October 2, 2019 at 3:32 pm

    i just drive my car without any exhaust, straight out of the head, zero exhaust restriction

  38. Sling_ _Sh0t October 2, 2019 at 5:23 pm

    Lmao stupid af.. On most "performance cars" the cats are not attached to the headers..

    You get coated headers so it cools better than stock manifolds..

    Get shortys for close to stock performance

    And not every car do you need to reprogram everything lol

    One of the worst videos ive seen

  39. Anthony Ellison October 3, 2019 at 2:51 am

    Scotty: you can't remove the cat from the car

    Me: watch this

  40. Star Boy October 3, 2019 at 4:56 am

    Scotty is great, but I don't think he knows just who puts those kind of mods on their cars. Yelling, "oh it cost money and it might break your car if done incorrectly" isn't exactly a deterrent rather it's a challenge to some.

  41. SPECIALIZED AUTO DETAIL AND RESTORATION October 3, 2019 at 4:57 am

    Riiiiiing up your smog plugs !!!!🏎️☎️🔌🔰🔰🔰🎌🏁🏁

  42. Crazycatman October 3, 2019 at 6:05 am

    Higher RPMS…. Racing… Street Driving???? Nah. I just floor it all the time, responsible tho. 2JZ sounds good.

  43. Crazycatman October 3, 2019 at 6:06 am

    Nah… headers first. You can't do turbo before headers, what are you talking about?

  44. Crazycatman October 3, 2019 at 6:08 am

    Screw it, I'm buy some "fancy" headers and yell through them, at Scotty! Money well spent!

  45. booostedtc October 3, 2019 at 4:50 pm

    Dont know what your talking about sorry

  46. RPG Features October 3, 2019 at 11:48 pm

    Have long tube headers on my 98 2 door Tahoe with hooker long tube headers at 90k. Still running strong with 220k

  47. illestfive0 October 4, 2019 at 12:08 am

    imagine building your motor, boosting it, AND THEN putting on headers…Scotty wtf lmao

  48. jonnda October 4, 2019 at 1:45 am

    Not every car needs the ECU to be reprogrammed for just a small boost in efficiency, Scotty.

  49. Alan Albright October 4, 2019 at 2:03 am

    Well I have a mechanic that inspects my truck even tho its technically "not street legal" and I dont have cats on my truck either so…theres that

  50. Mike Arellanes October 4, 2019 at 3:52 am

    This old fart can never say anything with out yelling….and he always says the opposite of what your soposed to do…

  51. happytimes724 October 4, 2019 at 5:40 am

    Thank you Sir. Great videos. I've been watching for years.

  52. Richard Kager October 6, 2019 at 1:10 am

    Anybody wanna' buy some headers?

  53. Jeremy hare October 6, 2019 at 3:47 am

    I hate this dude lol

  54. RNLJR T.C.B October 6, 2019 at 7:47 pm

    There's only one reason i like loud exhaust, i enjoy the dirty looks from my neigbors…..

  55. munajj khan October 7, 2019 at 11:09 am

    This guy is a CANCER to the car community

  56. Rasool Woods October 8, 2019 at 12:46 am

    Great advice for people that don’t have disposable income to throw at cars. Or men with 6 kids and a stay at home wife 👩‍🍳.

  57. Koda Reviews and Unboxing October 8, 2019 at 3:00 am

    Cracked manifold gotta keep it

  58. Dio Black October 8, 2019 at 8:46 am

    The one Scotty video i can say he's wrong.

  59. Tina Einstein October 9, 2019 at 5:22 am

    Next up: Don't start your engines. It will wear out your car.

  60. Lopez Art October 9, 2019 at 8:01 am

    You’re in Houston!!!!!!??????? Badass

  61. ninja z084 October 9, 2019 at 11:31 am

    My vrx has extractors stock . Better than cast iron to heavy.

  62. Pontiac Maniac October 9, 2019 at 8:10 pm

    No cats is the best way to go

  63. Jay October 10, 2019 at 2:15 am

    Rev it up. Your wheezing choked air intake and dont let any excess air out of your stock engine. I mean really? I like some of this guy's videos but he for sure don't like modified cars or trucks. Oh I'm sure he has a very restricted stock muffler as well.

  64. philmatoph October 11, 2019 at 3:21 am

    this why older cars are so much better for mods these new cars needs to reprogrammed for everything that you do to them .

  65. xBlueBerry October 11, 2019 at 8:08 am

    Honestly scotty is an old mechanic. And doesn't know all about modifying cars

  66. john mykel October 11, 2019 at 2:55 pm

    No hate but it’s funny. I have long tubes on my mustang with no cats and I live in mass. And I just passed Inspection some how lol.

  67. Samuel Karlsson October 11, 2019 at 5:14 pm

    Scotty loves backpressure…

  68. Isaac Rodriguez October 11, 2019 at 5:33 pm

    So basically what he said at 2:12 was to get a tune Lmaoo he tried to make it sound more complicated so that people won’t buy them 😂😂

  69. Elbert Cates October 12, 2019 at 1:59 am

    I'm really starting to think scotty is jus the old neighbor who hates modied cars lol

  70. Adam Webster October 13, 2019 at 11:22 pm

    You kinda need special headers to turbocharge an engine…. I mean, you could use the regular manifold, but the plumbing work would be more complicated

  71. Hcc Tendeep October 14, 2019 at 9:13 am

    But it sounds cooler when I press the gas

  72. Vin Commons October 14, 2019 at 12:45 pm

    Sorry Scotty I got a high flow catalytic converter in the mail as I type.

  73. Vin Commons October 14, 2019 at 12:47 pm

    You are making my stomach hurt.

  74. 4U Appliance Repair LLC October 14, 2019 at 12:54 pm

    Modern cars self adjust. (To a point) They have mass air sensors and wide band 02 sensors. If you just did a header and intake. I bet you would see a increase of performance and not have to reprogram anything.

  75. SIgnature Home design October 15, 2019 at 4:52 am

    I have a rule of thumb for mods on my Ram… Do EVERYTHING this guy says not to do.

  76. John Dean October 15, 2019 at 4:54 am

    There is so many things wrong with what he is saying its crazy. I feel bad for people ignorant enough to believe him.

  77. Capri 82 October 15, 2019 at 9:56 am

    Scotty shaves his chest

  78. Frontofax October 15, 2019 at 10:50 am

    Ok Scotty I get it now I will just get a prius.

  79. DukatiDoctor TARDIS October 15, 2019 at 8:39 pm

    My car is carbureted and old enough to not have emission tests. I’ve taken my entire exhaust manifold off. It sounds cool!

  80. Uncomfortable Truth October 15, 2019 at 10:01 pm

    1. No, stock is NOT optimized.
    2. No, you don't need expe sive tuning. fuel injection adapts on it's own within reasonable limits
    3. No it won't "mess up all the electronics and wiring", freaking nutjob
    4." It's against the laaah!!!" So?

    Scotty Kilmer is right about half the time and full of crap the other half. IDK why anyone likes him unless they don't know crap and take it all as gospel

  81. Cal Ripson October 15, 2019 at 11:28 pm

    Everyone loves headers, but he is actually right. If you remove the catalytic converters you actually void your auto insurance because you are now operating a non-street legal car. Theoretically, if you get in an accident and hurt or kill someone and they find out you have a non-street legal car, guess what….you are now on the hook for all the damages. No insurance coverage.

  82. ACCT Ahmed October 16, 2019 at 5:50 am

    Scott can shut the hell up I'm putting a shorty header with a cafback system this week, don't care whatcha say.

  83. Gina Giroux October 16, 2019 at 2:02 pm

    Honestly every video is you telling people what to do with there vehicle. You are entitled to your opinions but you are more than often wrong. All you do is crap on anything you don't like.

  84. draco man October 16, 2019 at 6:32 pm

    Scott, your the Ozzy of mechanics!

  85. Lithuanian GLOCK31_NH420 October 17, 2019 at 5:51 pm

    This guy just likes cars to be fit for woman…. dont worrie scotty. Open headers on my car will go faster than your car you douch.

  86. Lithuanian GLOCK31_NH420 October 17, 2019 at 5:57 pm

    Heat tape to prevent anything from touching the stainless thin walled headers. You can imagine if a spark plug wire touches the red hot header.

    And you should have said installing headers on an emissions equip computer controlled fuel injected modern vehicle. But it can and should be done if your building a car to go faster than mine.

  87. JackedJay October 17, 2019 at 9:24 pm

    Headers don't do much to backfire, my 04 Monte Carlo SS backfires with it's stock headers (I know headers and Manifolds are different but the Monte Carlo was built with them). All headers do is allow more flow through the cylinder as the exhaust valve opens. Manifold restrict this which can eventually cause damage to an engine in colder areas.

  88. Steven Marzullo October 18, 2019 at 4:58 am

    I put headers, intake, exhaust on my daily Acura TL and loved the gains it made, kind of loud but I never got pulled over for it. If you were not in the gas it was quiet enough to not even notice it.

    I ran stainless steel headers a 2.25" stainless steel flex pipe to a oem style cat, to a 2.25" resonator then it Y'd out to dual 2.25" straight pipes. No beyond 60 degree bends. Put autozone crome tips on the end of the pipes and it looked completely factory.

  89. MisterTonyG October 18, 2019 at 5:52 am

    This video is meant for people that don't know much about cars and all they do is either a CAI or headers and that's it. Headers and all that jazz are fun just as long as you are knowledgeable and you do it right with an endgame in mind. Obviously some vehicles are worth sinking money into and some aren't. The bigger your engine, the more potential as well as reliability there will be. Please research and inform yourselves. There's no hurry, take your time and double check everything. Do it right the first time.

  90. Darndiddlyarn October 18, 2019 at 6:58 am

    I'm surprised how 99% of ya'll completely missed his point. He's right, headers on a daily commuter are a complete waste of time, on a sunday car by all means put on every mod you can get your greasy little fingers on. My L98 gives me all the revs I need for the street with stock manifolds.

  91. Aaron Hamilton October 18, 2019 at 8:02 am

    LOL, what a goof

  92. Owen Conner October 19, 2019 at 1:23 pm

    I bought my headers for like 400$ from speed engineering and gained 23hp after re-tune(150$). So 550$ for 23hp was wort it big time. The biggest gains were actually under the curve at lower rpms. Buuuut, I don’t drive it every day, though I certainly could. But I agree that running headers on a daily is kinda dumb unless it’s making really big power. Not a 200-300hp ricer

  93. RevrendPD October 20, 2019 at 12:33 am

    Not sure where you're at but it's not illegal to not have a catalytic converter installed here. Hell I don't know how many I've thrown out and replaced with straight pipe.🤣

  94. Anonymous Person October 20, 2019 at 11:47 am

    Scotty if it’s too loud your too old. You sound like my grandma

  95. TrackMasterNate October 20, 2019 at 5:00 pm

    But headers make more power scotty

  96. David Salsedo October 21, 2019 at 7:43 am

    #1 reason to put headers on your car – Cuz racecar

  97. Anton M October 21, 2019 at 1:15 pm

    How else would one achieve a louder deeper sound if upgraded intake and headers with a tune is "just dumb." ???

  98. Charles Wilson October 22, 2019 at 11:45 am

    Lol if u drive a quite car in my area u belong in space. No one wants to deal with your boring swwwwwwwww sound behind the wheel

  99. omaduskilas October 22, 2019 at 9:15 pm


  100. Michael Mitchell October 23, 2019 at 1:51 am

    Normally I'm a quiet spectator, but I do need to interject here. I put stainless headers on my '03 Hyundai Elantra as an economy fix for my stock manifold, which was cracked in two places and creating noise at high RPMs. I got the stainless headers for about $80 on ebay, while a stock manifold+catalyst assembly would have been $280 at the absolute cheapest. Granted, I did have to go to a muffler shop and have my resonator pipe lengthened, but aside from that the new stainless headers were plug and play. I haven't noticed a major difference or increase in power or fuel consumption, but I can say that the engine runs very smoothly, and I have taken the car on multiple cross country trips. My O2 sensors have been doing a fine job of accounting for the difference in air/fuel. Elevated engine temps are a thing, but I don't have to worry about those either because of the hood scoop I added. Just some food for thought.

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