Megaphone & Collector extensions - Dyno Tested - Gold 4age

Dyno testing various shapes and lengths after headers / extractors. On a na 4age
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Insta : @garage4age
@Garage 4age

[@Garage4age]

Was planning on doing some more open header tests, but far too loud. Especially with the megaphone. Testing with a muffler is more relevant to what im doing, and guessing most people watching this. The real time graph freezing, was the pc/sofware recording the screen frizzing out due to the noise. I'm having to fight the odd zombie now after awaking the dead. The megaphone makes a fine weapon for that. Anyway looks like heading in the right direction with megaphone and downsizing collector outlet. Thoughts?

[@willdavidson4599]

I think moving the the start of the megaphone closer towards the collector would improve scavenging as the expanding exhaust gases would increase "vacuum" at that point. Much like the Venturi in a carby?

[@juhonmoottoripaja2443]

What about calculating a "proper" megaphone collector? The lenght would probably be near 350mm +/-20mm and choke section around 46...49mm (length 25.4mm). Megaphone start 47-50mm and end 67-71mm, with reverse cone length 31.8mm and end to 58-62mm. These are just very rough numbers, just as an example. Your test proves the megaphone collector seems to work, even tho length and other measurements may not be near the "optimal". I know atleast Pipemax can be used to calculate e.g headers (many designs) and the whole exhaust system length or just the collector. If you give all values required to calculate headers/collector , I can send you the measurements Pipemax gives - for testing purposes. Would be very interesting. But its not really an expensive software if you work with n/a engines, and do cylinder head work, intake manifolds and headers. But I want to thank you for the amount of testing you do. It's interesting to watch!

[@Garage4age]

@@willdavidson4599 It was like this in the last run in vid, didn't like it. Although good chance that the choke point was too big for it to work. Hence why the first megaphone setup tapered down before going back up

[@Garage4age]

@@juhonmoottoripaja2443 It isn't actually too far off those numbers. the choke point is 50mm od, so 47mm ish id. the megaphone angle probably isn't too far off either. is roughly 7 deg included angle. just goes up a lot bigger, as the plan was to cut it down to see what effect it had. would be interested to see what the pipemax program spits out. email if you like [e-mail]

[@TomoReso]

It would be logical that the first cone would help exhaust scavenging, but reverse cone is a surprise! Thats basically two stroke engine exhaust haha. I believe the longer the first cone, (less angle) the flatter the dyno result. (longer scavenging duration). The same goes in building the exhaust for two stroke. And same applies for reverse cone , but, reverse cone is here to build back pressure. Having larger angle should help scavenging on shorter range of rpm with better peak hp... and reverse cone too, but i somehow doubt that reverse cone lol. Reverse cone builds backpressure over the certain rpm range. Maybe when the valve overlap happens you could actually have some gains, at higher rpm? I was sure it could help (without reverse cone) to flatten some bad rpm range. And placement is crucial. Closer to the head favors higher rpm while lower rpm usually suffers. And vice versa. Your placement is pretty far, which is good for lower rpm. Tho this does apply for two stroke, i dont know how 4 stroke behaves, so your video is pure gold :)!

[@kujtek]

this channel is basically live automation game stream "lets change a little bit and run a dyno" lovin that

[@apesplanet3301]

well yor not learn anyhtinh, hes simple stuck with that engine with the same power just slight differences

[@kujtek]

@@apesplanet3301 thats all about it, you can clearly understand what makes difference or not

[@bass2762]

@@apesplanet3301obviously small changes arent supposed to give super big changes, the main idea is just to test what changing a variable does to the overall equation.

[@glenlancashire7974]

Dude it looks like a two stroke pipe!

[@jonathonbisset5328]

This mythbusting is awesome. Keep it coming

[@MrAndrius12]

These videos are so good and unique, that it makes me wonder - what morons keep putting thumbs down? We should be encouraging channels like this to shine!

[@kawaiirunnersdriftclub]

I love these testing videos. We can learn much from your experiments! Keep it up!!!

[@derxKai]

"Loud noises" xD xD Thank you Brotha. =)

[@martincoufalik9101]

Damn, that amount of work, thank you dude

[@GapSauceYoutube]

This is exactly the kind of content I need for my soul 😆 Thanks for going to the effort, I'm all about the back to back testing. I may try a similar style collector extension myself.

[@MrGivmedew]

Dude this is the best video I’ve seen on your channel! It just reminds me of how much we missed in the 90s and early 00s. It’s so amazing that we are still finding HP without technology except maybe the technology of making discussion and sharing knowledge easier. I mean I’m doing an engine swap I did 20 years ago (H series Honda into hatch) and there have been countless low tech improvements!!! It’s so amazing!

[@BushidoDriver]

This is awesome! Keep up the experimentation!

[@carSketcher]

Awesome testing as always. Good to see some evidence of lots of reading! Bought some merch, keep up the good shit.

[@jonnyretro2235]

Best tuning channel on YT. 👌🏻

[@Josh.Bowen.086]

Great, and interesting information. I’m close to being ready to build an exhaust for my 7AGE AE86 and this is very interesting to watch. Of course not an apples to apples comparison but good to see what may hurt what may not when planning my set up.

[@brianrichards782]

Very interesting and fantastic content

[@saxmusicmail]

There are formulas for the header, expansion section and the reducer section. I think these were in the "Two Stroke Tuner's Handbook" by Gordon Jennings. The book is long out of print, as far as I know, but a pdf can be found online. The lengths all depend on the tuned RPM. The diameter is related to the engine's displacement, how much air has to be moved. While it can be used over a range of RPM, it REALLY comes on strong at the tuned RPM. Often a muffler section is built over the reducing section, seen as a cylindrical pipe starting at the weld between the two cones. When run at resonance, with a 2-stroke, some of the air/fuel mix is drawn through the cylinder out into the header, then before the piston closes the exhaust port, which is taller, and therefore closes after the intake port, the air/fuel mix in the header is rammed back into the cylinder before the exhaust port closes, actually giving a supercharged effect.

[@monoracer_]

Awesome test, i always wanted to try stuf with expansion shaped tubes aswell intake as exhaust!

[@TheBukesde]

You are a crazy man, I love it! 😁

[@davidcakers6818]

I'm glad you put Brick in the intro, I have some much more energy now that I don't have to do the LOUD NOISES drill every time I watch one of your videos...

[@johndelta00]

Gotta appreciate the effort here.

[@Julezaz]

Thanks a lot! I hope in summer do some modes mr2!

[@bunning63]

I remember the air-cooled VW drag racers ran megaphones straight out the back, actually think they still do. Apparently worked well for them.

[@onemantwohands5224]

I dunno about you guys , but i feel lazy right now 😂❤ love it 😂😂

[@30YearOldBunta]

Having a high velocity in the intake and exhaust can make for huge gains. I wish I had more room in the engine bay for long tubes.

[@suronsoon8913]

Love the extractor, hopefully one day you make me one,,,

[@robingroeneveld4169]

Really nice and informative video's! Try a cone just after the collector, with different reduction diameters. You should be able to pick up a few kW and smoothen the torque curve....

[@MotoresAspirados]

I missed the subtitles, thank you for your tests.

[@simonbergamin167]

Hi you're video are awesome. Could you put a turbo on the exhaust of naturally aspirated engine ? I've always been wondering how big is the flow restriction induce by the turbo (which is the normally compensated by the boost on the intake side but anyway). Cheers

[@josemelendez4080]

Saludos eres un duro en tunning 💪💪

[@user-ho7qy4tx6v]

what i gathered from watching your video 1. not enough breathers = burning oil 2. your engine power output is not restricted by the exhaust. 3. you could have logged the AFRs on every run to see how much more or less air is flowing from the exhaust. I suggest that you do all the power mods like cams and turbo that will make your exhaust the restriction and do the test again and you will see how each affects power output

[@Garage4age]

1. Engine was built from 3 worn out and broken engines. only new parts in it were the bearings. not a breather issue 2. That's not the point of the video, 3. power curve shows the same thing. AFR change with the same injection rate is the poor mans dyno. if goes leaner you are making more power I wouldn't be testing megaphones and collectors then. I'd be testing how restrictive the exhaust is Some things need to work with other things, but good science is testing something without the influence of another thing. If went from a restrictive exhaust to a non restrictive exhaust, that happens to have a megaphone or different collector. there is no way to know where the gain / loss came from

[@user-ho7qy4tx6v]

@Garage4age how do you know for sure? 120kw is a very very good power output for a 4age na even at this power a 2inch system would yield the same results.

[@Garage4age]

@@user-ho7qy4tx6v big exhaust simulates exhaust ending after headers and collector section. if tune those parts right without restriction after them. can retain and even gain bottom end power with big cams (as well as the top end gains) over a stock cam engine. this engine makes more power everywhere than a stock engine and it runs 284/278 cams. It makes good power as it has all the good bolt on parts from my good engine which makes over 160kw

[@osvandremolinari]

Very good these tests, continue with this work, greetings from Brazil

[@MotoresAspirados]

Olha, um brasileiro só de tocaia kkkk

[@osvandremolinari]

@@MotoresAspirados brasileiro tá em todas, 🤣🤣🤛🏻🤛🏻🤛🏻

[@MotoresAspirados]

@@osvandremolinari tem os projeto loko aí tbm?

[@osvandremolinari]

@@MotoresAspirados começando hehehe qual seu insta?

[@MotoresAspirados]

@@osvandremolinari tenho um mas não uso muito, não aprendi a mexer kkkkk motoresaspirados

[@gedas3419]

Maybe you would try a few different header length and diameter setups? Like building an adjustable length header. F.e. starting off with a desight which would let all 4 go to collector as soon as possible, and just add extensions and try which would be best. Maybe even through the hood setup. Cheers for such a great videos, mate.

[@Garage4age]

Ive started to build some new headers, to drop in the same place. length will be the same, but will be making a few other changes. may do length at later date.

[@woodzy575]

Great video, you could try that setup but 3", 6", 9", 12" between header and that pipe to see if you can tune to get the negative pressure wave back to the exhaust port at the right time. great results. Thanks

[@ardisian]

Kind of what I was thinking too

[@Garage4age]

Yeah definitely the part that responds best to changes. Will probably try a few more things, to get it closer. but really need to wait till the good engine goes back in to get it dialed in.

[@tarantula441]

I am so glad u muted that ugly turbo sound on the intro that used to destroy my ears. Love u man! Awesome content as always

[@suronsoon8913]

Got your t-shirt, decel and sticker delivered, looked cool brother, I’m promoting you in Australia already...

[@suzukisport1]

I thought he already was an Australian?

[@tortron]

@@suzukisport1 not enough white leather interior and 22" simmons for that to be true

[@suronsoon8913]

I think he a kiwi, he love his dyno shed, including his sheep....hahaha, just joking bro...

[@turbotyoma]

Just love your channel! Tell me please, do you make AFR corrections with each mod or not?

[@Garage4age]

Yeah afr is corrected if needed

[@s2000Macedonia]

Great video..megafone (gern pipe) works..just a lot of work to try it out but i think its worth it..i didnt get it..does a short collector or long work better.. maybe try putting a smaller megaphone in the back of the car and a muffler and a longer collector pipe..this would be considered real world use i guess..

[@tonyfoxxbuilds1920]

I like the sound at 6:11

[@TheGuruStud]

megaphone on a performance engine will actually make a decent upgrade - interesting physics. It doesn't even need to be that long.

[@chipsnpeasifuplz]

2 stroke pipe on a 4 stroke 💪

[@DavidLyon]

A horn muffler might not be as good as a reverse-horn muffler. What I mean is that as the gasses cool from the engine they contract. So going into a horn means that they need to lose energy and that energy will come from the engine power. Many new cars therefore have a restriction just before or after the muffler to keep the pressure up and flow-rate going faster.

[@appelmelk5664]

Nice 2 stroke pipe bro

[@magnusdanielsson2749]

Always interesting so watch your vids. Have you tried anti-reversion chambers on the exhaust? Also a 4-2-1 headers is claimed by many to be superior. Had any thoughts on that?

[@riseabovw]

yeah.... here in sweden as you know they reign supreme :D there is power in the midrange to be had with 4-2-1 for sure .... otherwise motordesign wouldnt run them :D

[@magnusdanielsson2749]

@@riseabovw on the other hand people like ”headers by Ed” claim that a properly designed 4-1 header always makes more hp

[@BiTurbo228]

@@magnusdanielsson2749 4-1 will make more power as its design favours the top-end. 4-2-1 has a broader effect, so your midrange will be fatter but your top end won't be improved quite as much as with a 4-1.

[@cirokietyka692]

Plz next lightweight flywheel vs heavy Saudações do Brasil

[@ShortysTRM]

Dude, again, fun to watch the fab and crazy to see the results that I didn't expect at all. Since you've been testing the increasing/decreasing diameter theory, think you could make a megaphone that transitions over a longer distance, but still doesn't become ridiculously large? Like 3"-5" but 4 feet in length? I see how hard it is to fab them, so I know it's a pain, but your "subscribe" message etched on this one made me subscribe, and I don't subscribe to anyone usually lol

[@Garage4age]

Yeah can probably run a little bit lower angle. this one is getting towards the max it should be. once i'm happy with a setup. plan was to make an oval item that fits under the car and hope it still works the same.

[@rolandotillit2867]

I have a good idea, try a two stroke scavenger exhaust after the megaphone tapers back down, then put the muffler after that.

[@TheSol115]

More more more videossss 😛🚀🚀🚀🔥🔥🚀🚀🚀🚀

[@tuomashayrinen4763]

This is getting close to my setup. Try it with a merge collector.

[@brycelevipillay]

Hi please do a test 4-1 vs 4-2-1 headers. Also the affects of different size exhaust coming out of the header and what that does to torque and power

[@remybrouwer8700]

If I see all the runs, it seems to me that the pipe is actually a little large on diameter, for the size of the engine and the output, 2.5" IMO is killing velocity and there for scavenging, I do believe that 2.25" is the magic bullet but make that pipe section from the collector to the megaphone a little longer for about 8", and the transition from the collector to the 2.25" as smooth as possible so the velocity increasy is more effective and there for the scavenging, you will need to see what will happen to Cyl #4 AFR.

[@johnpublic168]

Great tests, Love your data gathering. I found that the collector length is very important. What is the Meg divergent angle.

[@Garage4age]

around 7 degrees included angle from memory

[@johnpublic168]

@@Garage4age 7 to 11 degrees seems to work well the bigger the angle the shorter rpm band it's effective. And becomes sensitive to tuning.

[@luistorreslopez2761]

Me gusta todo los trabajo

[@Stephan.Martin]

Thanks for all this tests! Would you give alternative fuels a try? Like switching to E85 (Ethanol) ? Should give more room to ignition

[@MrGivmedew]

Do we know the availability where he is? It’s all over the US because of corn but I wonder about his area…

[@Stephan.Martin]

@@MrGivmedew good point, here in europe its disappearing now. but still it would be interesting to see :-)

[@ToolsOutsideTheBox]

Interesting. What about adding a resonator?

[@wraithgard]

Im trying to maximize mid-range power on a stock 4age big port. Should I just use stock runner size and lengths? Would longer/larger runners only decrease my power below 6krpm? I'm trying to figure out my best setup between stock, 20v ST header, and TRD 4-2-1

[@tiitsaul9036]

Interesting.

[@copisetic1104]

Reverse cones are really hard to get right on multiple cylinder engines. I have run countless simulations on prof Blair’s software.

[@SMVB-cl6oc]

Can you test if octane booster can be used with 98? As in can you add more timing if you mix them

[@50cal974]

What about comparing smaller middle box vs bigger back box and vise verses?

[@hannurissanen9971]

You should use a can having huge overlap, when using really sinking pipe.

[@thebowtieguy777]

Are you gonna try out different megaphone sizes?

[@apcjonker]

Have you ever considered going on Patreon? I would support you for this great research.

[@Garage4age]

Thanks. I should probably look into it. At the moment it costs me more to make the videos than what youtube pays.

[@FineW_TurboM111]

How about trying if heat wrapping the whole exhaust makes it better?

[@MatthewWillard99]

PLEASE DO AN X to Y PIPE FROM THE BOTTOM OF THE HEADERS, X THE TWO BANKS TOGETHER! In theory should help scavenging? It’ll be a bit of work but I’m intrigued to see the power, sound and response differences!

[@MrOhai1337]

Hey mate, what brand dyno is this out of curiosity? love the vids!

[@Garage4age]

hey. its an old vane bed (now mainline) running dynotorque software.

[@martokisful]

Unexpected results 5kw is a fuckton, seems like the 2.5" section normalize the flow entering the mega. Could you try making the front section longer and maybe putting a muffler before the mega with and without a front section that normalize it? To see what the flow thinks

[@Funtik.]

Спасибо мужик 👍🏻

[@theartof...7755]

You should test an anti reversion chamber!

[@mopoworks7780]

Try making the pipe before the cone a bit longer. Should result in more low end

[@ricepony33]

I would think a more traditional shorter 4-1 header and a 2” exhaust with a muffler way out back would be the best real world solution. More bottom end and midrange with higher exhaust velocity and some scarification of peak numbers but less than a 4-2-1 header. Check out thecarpassion channel for an interesting look at intake lengths on the Miata.

[@Garage4age]

If you watch my previous videos, where i tested the 60mm exhaust. this isn't really the case. It lost a lot of power down low with 60mm all the way and a muffler at rear. the front section to the first muffler and placement is critical to making the low end power

[@matthewmorgan584]

I need to read up on the way exhausts flow, I am so confused on why removing the 2.5" lowerd the power

[@thomasroth4695]

Step headers? And a better collector maybe. Short intake runners for top end

[@jpm9014]

Have u make the collector smaller? Im waiting for your uploads, really enjoy your content, thumbs up!

[@Garage4age]

Will be doing some more development at a later date, when my good engine is back in the car. since that will dictate how small can go in various parts

[@tejdz1337]

try port matching intake parts !!! im very curious how much this does

[@Garage4age]

will do at some stage. As i want to say it will do next to nothing, unless very bad to start with. but have never back to back tested it

[@KarolisSiauliai]

Interesting as always. The headers manifold is the best which you always use, right? What diameter they are? Never thinked that a 2stroke looking pipe could be good on a foustroke engine.

[@Garage4age]

Yeah the "small" headers which are on the car most of the time were used in all the tests in this vid. they are approx 35mm id

[@KarolisSiauliai]

so generally in your car is better small header (35mm) with big pipe (3"), than viceversa, 38->44mm header with smaller pipe (60mm) . Are there some engine config where the big header and small pipe would work?

[@AmaroqStarwind]

How many mufflers does it take to make the engine sound almost silent?

[@BadAssEngineering]

Have you tried a straight 2.0 or 2.5 inch straight pipe? Maybe a smaller diameter would make better work of the exhaust pulses, 3" and megaphone seems like too wide for that engine to take advantage of

[@Garage4age]

Go back a few vids to the bolt on mismatches vid and the one after it. i tested a 60mm system. its the first part of the exhaust that matters

[@cumminsfj4586]

Header looks nice as. I bet this is hella loud in person

[@Garage4age]

Very!

[@juha-mattimalmstrom4095]

This "old skool"set up tested dyno early 60ties..motorcycles.. But todays evryfear it noise limits.. Track,road eaven dragracing..

[@vincentrobinette1507]

You'll find that the header primary pipes make a bigger difference, than what happens past the collector.

[@jamest.5001]

So it's about like an expansion chamber but for multiple cylinders? I thought about something like this, but for the down pipe on a turbo, say if it's a 3" outlets, have about 4-6" of 3" pipe, then go to 4" maybe 5" for about 3" -6" possibly 8", then backto the 3" with up to 180° of bends , probably it would be best to have the bends in the larger pipe! Be at a bend has the same effect as a smaller pipe, dropping diameter over about 2-3", but I guess the same pipe could fit on a header collector, The swirling chaos from a turbo, can likely take advantage of the larger pipe to get the flow in order as it is reconstructed as the pipe diameter is reduced, it can be difficult to build if tooling is a issue. I would like to see it tested !! Maybe it could offer gains over a open turbo, and a standard head pipe,

[@fernandohood5542]

Difference will be shown in the the size and length of the primary runners.

[@babaadonf]

It's like a 2t... . If you look, some header have a megaphone just after the 4 in 1...

[@yurivistavkin4740]

👍

[@kingmarz3635]

Hey man where abouts you at in NZ? Can you tune me truck?

[@rolandotillit2867]

Apparently the megaphone needs to be 4x the displacement of 1 cylinder or twice the displacement of a 4 cylinder engine.

[@thegabrielcwb]

If you put the muffler before the mega, wouldn’t the mega work better than this setup?

[@jameshinged3002]

For the first portion of the megaphone what was the tamper angle it expands , and for the second what is that one dis expanding looking at a catalog at precision made cones to slap onto my car (Ik every car will be different I have the id od set just confused on the expansion angle )

[@Garage4age]

This one was around 7degrees from memory. Can't remember what the reverse cone angle was. Different angles will work better Different rpm

[@jameshinged3002]

@@Garage4age this is what I saw on coneeng , 13° was for high hp, 9° was a comprise of 7° and 13°, and 7° was low end , and let me clarify the cone that is the inlet to 2.5” adapter is the reverse cone then met with the 7° cone correct

[@ocsotdi]

Next test tip.. Helmholtz resonator? 🙂

[@athiam152]

Noodles FTW

[@AmaroqStarwind]

"The complete accessory kit includes... Silencer, Loudener, and _this_ is for shooting down police helicopters!"

[@jute91]

Try dropping the outlet of the collector to smaller size. You should try where it starts to resist the most. step it down by every size you can find. Google Laval Nozzle to find out what I mean

[@Garage4age]

Yeah that was the plan next. I'm actually making some new headers that will make it easier to run a smaller "choke point"

[@Liveforeever]

So a 2" choke point gave best power low down and high up?

[@Garage4age]

looks like the megaphone is helping a little overall. and the 2" choke point helps the bottom end. As when changing to the 2.5" section top end is the same, but a loss down low. I'm interested to see how small can go on the "choke point" before it losses up top. or stops gaining down low

[@Liveforeever]

@@Garage4age what is the megaphone doing exactly to overcome the choke point?

[@Garage4age]

@@Liveforeever way i understand it, is its some kinda wizardry. that lowers pressure on the engine side of the choke point. so should be able to run a smaller choke point to increase scavenging. the angle of the megaphone has to be correct for it to work

[@MrIngorodrigues]

Try thermal wrap

[@s4ripper]

The first baseline dyno has your normal 3in exhaust?

[@Garage4age]

Yeah is the normal 3" system on the car, which works pretty good. so any gains over that is doing pretty well.

[@s4ripper]

Are you using the same baseline exhaust with your other more powerful engine too?

[@user-ys7hz9ls6x]

Heat isolation, please!

[@williamwarner3982]

Head pipe is too big for the power. Try 2". 1.5" maybe a bit small but a good match for under 150 HP. Love the megaphone. Hehehe.

[@Garage4age]

Has 1.5 inch primarys. They good for over 200whp

[@williamwarner3982]

@@Garage4age yepr. Just stating you can go too big.

[@dog283spec]

This is making it look like it's worth it to spend making a megaphone with reverse cone.

[@piciu256]

So, I reckon by having an empty cat box directly by the manifold (factory spot) I'm losing a bit of low end torque 🤔

[@Garage4age]

replace it with the biggest glass pack straight though you can fit

[@piciu256]

@@Garage4age good advice, might do, they aren't too expensive, might remove the terrible resonance noise while at it, I'm not too concerned with power as it has enough grunt down low for general driving, but I really don't like what hollowing out the cat did to the engine sound.

[@fuzz378]

why not 421?