Exhaust Header – Explained

Exhaust Header – Explained

Hello everyone and welcome to this week’s video today, I’m gonna be explaining exhaust headers and uh exhaust headers are basically one more step if you are working on getting a full new exhaust with larger diameter of piping throughout it So if you haven’t yet watched my video on cat back exhaust or my video on how to increase horse power via the exhaust should probably check out those first, i’ll include links in the description Now this particular exhaust header is a
Yonaka header for Acura Integra b-series engines and so I’m just gonna
be kind of going over this and how these are used to increase horsepower so the exhaust header is the first
piping after the exhaust from the engine exits through the cylinder head and
starts to leave out of the car, so the purpose of a performance exhaust header is clearly to increase horsepower Now it does this with two main ways: first of all, it’s going to have larger
piping so for example with this Yonaka header it’s going
to have one in five eighths piping for the primary pipes coming out and then it
is also going to have a 2.5 inch collector, the collector is where all of
the individual types join together and then go out to the exhaust as one
throughout the rest of the system. So, the other thing this does is it supports
scavenging, so the longer these long tubes support exhaust scavenging so if
you’ve watched my video on how exhaust can be used to increase horsepower you should be able to understand that as
far as how scavenging is done in order to increase horsepower. So one of the things that’s common with after market exhausts, especially in the Honda Acura Japanese market world
where we’ve got four cylinder engines is a four-to-one header or a 4-to-2-to-1 header
and basically all that is is describing how the piping joints together and
finally forms into one so the 4-to-1 you take all four and then
they just go to one just like the name is when the 4-to-2-to-1 two of the pipes
joined together and then finally the only after that so little difference and I
look at some dyno charts online just kind of see some main differences here
and it doesn’t look like there’s a huge main difference but the powerband
shifted a little bit hotter with the 4-to-1 rather than the 4-to-2-to-1 so this is a very exaggerated curve here, but basically you have torque on one side and RPM on the other the 4-to-2-to-1 header
is going to kind of have its peak torque a little bit lower rpm than the 4-to-1 header and once again at the graphs I looked at online it didn’t seem
to be a huge difference so it’s not anything major like I’ve shown here and
then both of them seem to have a decent advantage over the stock if you did have
an engine with a significant amount of power. So of course with these kind of
things with the larger piping you’re going to want to match it to your
horsepower so it’s not necessarily if you have very little force arranging
getting larger header may not be beneficial and I kind of go more into
this in my video on catbacks that’s kind of why I reference checking that out, but
Yonaka says the header that they supply is good for about five to 10
horsepower on the stock engines and of course that’s more effective if you have
a more powerful engine. One of the things with these pipes is
the large you create these individual pipes and larger the collector is your
kind of shifting where the peak torque is going to occur to a higher rpm so
larger piping you’re going to have a better flow at higher rpm when you’ve
got a lot more flow so it’ll kind of shift that torque that peak torque up
into the higher rpms. Some of the challenges
involved with an exhaust header, especially one with longer length pipes
is that the install can be kind of a little more complicated where you may have to remove some
components, move components and also weld the end on to the catalytic
converter or the rest of the exhaust that you’ve got going on also you can run into clearance issues
especially with lower cars as this exhausted or maybe the lowest part in
your car and so if that’s the case you want to make sure that’s kind of
protected or that it’s not really that low for the area that you’re driving in so just taking a look at this Yonaka
header, this is a stainless steel header and you can see the one and five-eighths
inch piping heading down and that all means up to a collector and then at that
collector you’ve got a 2.5 inch piping and that’s the outer diameter so the
inner diameter is actually little bit smaller and then here is where you can i
install the o2 sensor. I can just place that right in there. So, thanks for watching if you have any questions or comments feel free to leave them below and I will include a product include a product link in the descrition

About the Author: Michael Flood


  1. hey wat about if i have an s4 with bigger turboes and i have it straight piped 3" exhaust and i wanna put a stock muffler back on am i gonna be losing that much power or? (because of the stock muffler)

  2. i have a 99 integra with a b18 (non vtec) will this header fit it. I know it said for all B series i just want to double check.

  3. Hi can you make an explanation video why inline four sports bike produces a roaring exhaust sound and why a single cylinder or v twin engine won't.

  4. i have a question, whats the difference between SHORT and LONG tube? (exhayst manifolds)
    i wanna put top mounts for my nissan 300zx z32 (vg30dett) and i was wondering if i have any problem with the long tube.. :/

  5. what kind of headers should I get, I have a 2.3l i4 with roughly 100hp, it's already straight piped just wondering if 4-2-1 or 4-1 is better. Also I'm getting them custom made.

  6. sir my question is if the if i have an v6 so should is use two 3-1 exhaust header?? ,n sir can u help me if i want to make an v6 engine which can produce around 600hp , but still i want a bit fule econome so if i m in 24h race i will make less pit stops in the race
    plzz reply , TYVM

  7. Will i need to take off my performance headers from my car if I want to install a turbo? I saw that for most turbo kits they need a specific "turbo header". Sorry for a newbie question I've just really gotten into car modding. I installed headers/catback exhaust and a Cold air intake and its been really fun to feel the extra 30 hp it's all given me and want to take it a step further. Please and Thankyou!

  8. Hey Mate,
    Could you do one for a turbo vehicle?

    I have heard many mixed things from both forums and experts all contradicting each other

    Cheers, keep up the awesome vids love them

  9. Hi Sir, I watched your videos and feel impressive! What amazing! I am also a fan to refit my vehicle and desire to improve performance for acceleration. But recently there is one issue making me confused and frustrated. So i really want to consult with you to get suggestion from you. My vehicle is Jaguar F-Pace 3.0 V6 supercharged gasoline. I installed a pair of downpipes with 200 cell catalyst converters in series respectively(see attached photo) instead of original one. And I tested the acceleration and found out there is torque lost at front range and no any improvement at mid&later range….i don't understand where it goes wrong. I am really looking forward to your reply. Thank you very much.!!

  10. im planning to remove my resonator and upgrade my pipes into a stainless steel 2.5in pipes and change my stock muffler into a freeflow muffler.. my question is can i gain a horsepower into it?? thanks for more info you shared

  11. i really wanted to know why there's a stainless steel aftermarket exhaust headers costs like 1500 $ and another company selling another stainless steel headers for 750$ how can you tell which is better and what makes the difference between them ?

  12. I want a Subaru UEL header like rumble but can't because I have no exhaust manifold, is it possible to get the same rumble effect I make one pipe on the catback longer than on the other side?

  13. Can you make a video on how a powerbomb header works and wether or not they create power? I look all over online and it seems to be a 50/50 on results.

  14. Is there a specific equation that you could use to determine the best, most efficient diameter tube to use based on engine and desired horsepower/torque? For example, if you have a 5.7L Hemi and want to produce 500ft/tq. What diameter tubing would be best?

  15. I've a small amounts of fund& I dont know which upgrade is better for torque of my car. My car is 1.2cc with mileage close to 200k. So, should I buy an aftermarket alloy rims to replace stock alloy rim which Very heavy or replacing stock header to 4-2-1 header? Hope somebody could help me out, thanks🕵

  16. I like that you talked a bit about the types of collector designs.  If you look at some of the nascar cup car headers, they have various designs including 4-1 and 4-2-1 for each cylinder bank, as well as various pipe diameters of each step.  It's really just tuning based on the track they're running, but it's surprising to see so many different configurations.

  17. Either you read a few pages or u watch this guy. The physics behind it is important to know for your next step in truck or car mods! Thanks bro

  18. I suggest you to talk about the droning effect . I've installed a 4-1 OBX header with a magnaflow catback on my golf 2.0 and the droning inside the car is just sick, destroyng my ears. I caped one of the output pipe of the muffler to retain some back pressure. returning like standard "performance" it fix the noise quite good, but it no longer work very much now. at least ,I can just remove the cap if i want …

  19. Hello, I have a 2000 F150 4×2,auto trans,4.6 V8 2 valve engine.
    Will short tube headers make more hp/tq on the low to mid range,or will it make it at the higher rpms?

  20. okay so hears a question for you that I've always wanted to know. i drive a subaru and the have a 4-2-1 exhaust header. now in theory if i ran duel exhausts from both sides of the motor basically covering the header system to a 2-1 would that increase power efficiency and whatnot? I'm VERY curious to know.

  21. I apologize if you covered this, If you want to replace your stock exhaust header with something with larging piping, how would you connect the larger piping to where it connects to the engine? I'm guessing it has a specific diameter. I didn't know if there was another piece you would connect to make it fit or not. I love you videos I'm learning so much.I also have a vw rabbit a/t 2007 2.5 that I would like to start fixing up.

  22. got a DOHC B16a3 VTEC DEL SOL, with this style 4-1 header? had clearance issues now swapped out for a better 4-2-1 style with 4-2 in Y shape to – 1 2.5inch collector, seems to helped my lower RPM tourqe curve? allot better than the 4-1 did??

    B16a3 Vtec stage 1 cams (NA) mildly tuned ecu chip? (lloking to get an Eng. management system, or a Hondata ecu kit?

    tips on finding the best Vtec point or Crossover? im new to the Vtec B series

  23. Can you do comparison for ceramic coating for exhaust headers and some kind of thermo isolation tapes for more performance of engine? Is it true, cost-effect, etc.

  24. I’m guessing you can’t just replace one side with headers while leaving the manifold on the other side?

  25. Bloody Hell ! kathrynck I Fully Respect your Knowledge and I do Like your Comment BUT I had to go and have a Lay down half way thru and I'm a Car Technician L.O.L. 
    Very Educational.

  26. why isn't a "two point five" inch pipe called " two and one half" in pipe? in line with other measurements like 1 and 5 by 8 inch etc? OR just stick to the more human decimal system? good explanation though..liked it

  27. In the title description it says "how headers increase horsepower…In this video right off the bat you say the longer tubes increase scavaging which increases horsepower-watch my other video to learn how scavaging affects horsepower???I stopped the video at that point,typed this comment and moved on…

  28. Engineering explained… Can yiu make a video about engine heats externally?? And may I ask. Are headers wrap recommended?? if so, how much hp increase should I get?

  29. Could someone tell me what a test pipe that connect to these are for? Like in what situation would I want a test pipe? Cheers

  30. Nice job on this video. You really should discuss the primary pipe length as it is the single biggest factor for the tuned header. A shorter pipe length move the peak torque higher up the RPM band while a longer pipe length moves this down the RPM scale.

  31. When installing headers is it best to get tuned same time or it doesn't matter? As in causing damage.

  32. Heyy saw alot of awsome things on your chanel and in the comments I'm jus a guy working to make my car fun…. But here is something that I was hoping to get some fun ideas about I have a D16y8 550cc injectors nothing touched in the motor yet lol but I do have 4-2-1 headers jus got them I have a wider exaust and resinator 3 inch now will this cause some back pressure but still allow breathing properly in theory I'm about to bore the headers before I install for a smoother gas upstream down stream exchange it makes sense on 4-1 and why its better any thoughts and yes I will keep updated on my results I have videos of now w the factory headers and swapped injectors factory exaust id love to hear some input and haters please apply I love hearing all thoughts

  33. Do you think that by tunning the lenght of the primary runners on a 4×1 exhaust of a regular inline 4 cylinder engine (flatplane), one could tune it to sound like half V8 (one bank of the V8 engine)? I've tried to think of it as the time each of the 4 exhaust pulses take to get to the colector and thus interfere each other, considering one side of a V8.

    Another example: the crossplane crank inline 4 cylinder Yamaha bike: it sounds amazing because it is a 'half V8'. I've tried to think of the mathmatics of the pulses interferences as the time it gets to hit the collector, by selecting different lenghts of primary. It would probably hit performance but possibly create a great sound. And the performance loss could be offset by boost.

  34. I am thinking about replacing my exhaust header in my 2014 miata with a GWR roadster sport street header (catted). Would I be able to feel the difference in performance and is is worth the money and time?
    Please advise. Great videos by the way.

Leave a Reply

Your email address will not be published. Required fields are marked *