We progressively narrow the tailpipe - when will the car refuse to run?

Grab some G54 merch here - www.en.garage54.ru/
How tiny can the tailpipe be for the car to still be able to run?
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[@MuddafukhingdisKUST]

this is a car's equivalent of getting constipation.

[@droseyz]

😂😂

[@wildfirephoenix2262]

lol so true 😂😂🤣🤣🤣🤣🤣🤣🤣🤣🤣🤣🤣🤣🤣🤣🤣🤣🤣

[@towerofresonance4877]

I heard a big thunderclap after reading this.

[@SoulAir]

It's more like covid

[@boknow5506]

I wonder how much muffler back threw the air filter

[@docgiggles130]

U-Haul rental trucks in the US used to use exhaust restriction as a speed limiter. I know this because a rental truck I was driving blew the pipe off under the cab when I was driving on the highway. I was doing the limited 63mph when I head a loud bang, back of the truck bounced as it ran over the part of the exhaust that fell off, got very loud and the truck suddenly started to accelerate. It hit 80mph before I lifted my foot. I pulled over and crawled under to see what had happened and found it had dropped a 4 foot section of pipe off. After making sure there were no wires, fuel lines or anything else that could get burned, I got back on the road and finished my drive. I was amazed at how much better the truck ran overall.

[@Christdeliverme]

Terrible on fuel economy with exhaust restriction

[@mysock351C]

The bad ol' days before ECUs and electronic limiters. Same thing with school buses. Used to see them with the squashed tail pipes, and yet they'd be bitching about fuel costs and diesel emissions. Well duhhh...

[@docgiggles130]

@@mysock351C Honestly I wouldn't be surprised if U-Haul still used exhaust restriction as a speed limiter. They are not the ones paying for the fuel after all.

[@Shannon-Smith]

Back in the old days, we used to put blocks of wood under the accelerator pedals so people could only put their foot 1/2 way down for the same effect.

[@brentsnocomgaming7813]

Honestly I reckon they still do, I rented a U-haul van recently and even tho it had the V10 it was slow as all hell, even unloaded, and it was the strangest sounding V10 I've ever heard.

[@ShiestyFilmz]

this man acts out all my intrusive thoughts as a mechanic i love it😭

[@linksadude1]

Same!

[@alexutzusrl100]

Shower thoughts

[@DigBipper188]

that 10mm one is basically like driving a diesel car with a clogged DPF. Fun times.

[@iuse9646]

Maybe even better depending on the condition

[@Eduardo_Espinoza]

Was thinking it ran like a diesel too, just by having the throttle open all the time

[@DigBipper188]

@@iuse9646 it has to be fairly severe to cause the engine to struggle to rev in all fairness. Usually it'll throw DPF restriction codes if it sees around 4PSI pressure differential across the DPF and fails to do a regen due to insufficient EGTs. If a static regen or the right driving conditions aren't met to do a mobile regen it will just worsen until you can barely get it to rev.

[@drsquirrel00]

One thing to remember that the difference between 10 to 15 is much less than 15 to 20

[@crapcopter]

As soon as the dpf throws issues, just delete it hahahaha

[@benjaminrich9396]

It's a shame a pressure gauge wasn't measuring the exact back pressure for each of these. I'd be interested. Great video though. :)

[@gabrielv.4358]

I bet 1 bar lol

[@Wasophangen]

@@gabrielv.4358more i think easy 5 bar

[@MarkoDash]

Or the velocity of the exhaust coming out, I'll bet it was really moving at about 10mm

[@volvo09]

Did you see the video where they put a ball valve on the exhaust to try and explode a muffler? There was some pretty high pressure, i'm guessing around 4 or 5 bar just from the sound and how that thick heavy muffler deformed.

[@nickoloes]

Was going to suggest this myself...

[@mannbat]

The difference between 3mm and 4.5mm might not seem like much, however the volume that can pass through is more than double, so it's actually quite a significant step up.

[@mann_idonotreadreplies]

cool story bro

[@paradiselost9946]

pi r squared

[@waldolemmer]

2.25 as much, to be exact

[@DjClarky78]

@@mann_idonotreadreplies That's maths.

[@Mantis_Toboggan]

@@DjClarky78 imagine mathing

[@Dataanti]

When I was a kid, me and one of my friends clogged his dads tail pipe on purpose, just being destructive brats i guess. I remember that it stayed clogged for days until he noticed flies were gathering around the tail pipe (we used many potatos... and it was hot summer days, with the heat of the exhause system, it was rotten pretty quick) turns out the car did not notice to much because there were exhaust leaks throughout the system, which he then found out about XD

[@huzudra]

Once used an apple to plug the pipe on a friends car to confirm a leaking exhaust manifold gasket. Started the car after replacement forgetting the apple in there. Shot the apple across the street after about 10 seconds!

[@eklhaft4531]

I used to own and old Lada. I always smelled exhaust gases inside so open window was a must. Interestingly though it always passed the inspection :D

[@Spirit01_official]

😂😂😂

[@DUKE_of_RAMBLE]

Was this at all inspired by the movie _Beverly Hills Cop?_ 🤣 If not, the main character shoved a bunch of bandanas in the tailpipe of the cops that were observing him, allowing him to ditch them. 😊

[@SoldfMC]

How many headbolts can you remove before the engine loses all compression.

[@Dragoslav_MD]

Two is usually enough

[@johnbelwell2461]

Northstar V8 entered the chat

[@nowiecoche]

@@johnbelwell2461 😆😆

[@romangervaise35]

Damn genius ! Just hope the head doesn't fly in your face

[@johnfloyd2551]

How fast can you change the oil with the engine running before it blows up?

[@ogwubba]

Normally I wouldn't watch non english speaking youtubers, but this guy has quality content. Keep it up Garage 54!

[@Gizmos_and_stuff]

Same! I also like the translator's voice :)

[@atticusnicol151]

I'm surprised they didn't lose the 10mm one 😂

[@alexfelice4676]

needs more likes

[@ant16rst]

I think an economy test would be interesting with these exhaust tips!

[@cahydra]

Imagine someone makes a game where you can customize your car in all the ways that these guys have

[@yz934]

There's a game called automation, check it out

[@ATruckCampbell]

@@yz934 I play it, but the level of customization isn't and never will be anywhere close to what these Slavs can do.

[@nicholassadler3520]

BeamNG is also pretty cool, been playing it for years

[@chickerinoradio6617]

beamng is the closest right now with constant updates every few months, some people have gotten crazy things running in there, like a theoretical 100k rpm engine through mods, but it doesnt have the customisation level of modifying the exhaust diameter yet for instance

[@Ross-ql9fi]

The garage drinking in Detroit is the game you want it's expensive for good safety but lmk if u have the $

[@oldsoul5263]

Dyno time!! Please! Pretty please! Lol It would be interesting to see what the first couple restrictions did to hp being he mentioned something about feeling a little improvement.

[@AlbertDongler]

Reversion

[@crimsonhalo13]

"Is the diameter of that orifice sufficient?" A question as old as time.

[@KrasYnek]

I've got an idea. How a bout making a valve in the exhaust that would close when brakes are applied to make it an exhaust brake?

[@Dimondminer11]

Oooo thats an interesting idea

[@BillCut]

Brilliant

[@matthewmorgan582]

There is something very similar to that called a jake brake. They use them in semi trucks to keep the brakes from overheating. Exhaust brake wouldn't work because when you let off the gas it stops injecting fuel at least in an EFI engine. Jake brakes work by opening the exhaust during compression and basically turning the engine into an air compressor.

[@KrasYnek]

@@matthewmorgan582 I'm aware of those and I wanted to create similar thing. And I think it Jake brakes actually work by not opening exhaust valves till much later in the exhaust portion of piston movement. Hence the cool sound. It would also work on Lada as fuel injected or not it still pushehs some air through the engine. It's even proven to work during the video when a very small hole is on and Wlad let's off he says himself that he can feel strong engine braking.

[@Vicus_of_Utrecht]

@@matthewmorgan582 You can even see him lunge forward lol

[@TheChrisLeone]

Thank goodness there's a translated version, this is one of the best automotive channels I've ever seen. Good combo of funny moments, good engineering, and answering random but very interesting questions 😊

[@boronat1]

it would be interesting to see the powerband graph on each hole diameter

[@Zach-ju5vi]

I think you'd see the power band shift to a lower rpm.

[@BlackCatRedScarf]

Since that's a carburator engine, it would be interesting to observe the mixture with a wideband oxygen sensor.

[@throttleblipsntwistedgrips1992]

The amount of blowby would be the data you want. Intake is still going to see around the same amount of vacuum, at least at idle. Fuel curve really isn't going to do much in a carb, since it's velocity fed anyway

[@CarsandCats]

@@throttleblipsntwistedgrips1992 Not true. The more backpressure, the richer it will run. Same reason when you go to a free flowing can on a bike you have to go larger on the jets (opposite situation).

[@boknow5506]

​@@CarsandCats ha Mercedes has four cats yes two by two and 16 spark plugs yep on a V8 those Germans still sticking it to us

[@matthewmorgan582]

@@boknow5506 It's a Mercedes. Dual spark plugs burn more efficiently. It's all for emissions.

[@boknow5506]

@@matthewmorgan582 emissions ha so if I pay for more cats and the weight and more fuel how is it saving emissions

[@exploranator]

I theorize that if you increase backpressure and increase performance, then the car was running too lean before modification.

[@asjmpickle]

I had a 3.0L Cressida with twin 1" straight pipes from header back. I thought they were 1.5" until I measured it because it looked smaller than I thought.

[@dream-zf1th]

very cool car

[@TonicofSonic]

What about 6 mufflers for a shot at the world's most quiet combustion vehicle?

[@jackfrombg4498]

Garage54 really needs a dyno. Seeing the numbers during these tests will be just PHENOMENAL.

[@jasonschlencker8108]

Great vid! 25mm exhaust pipes were used on heaps of small 4 and still 3 pot cars today. The pipe restriction would have more of a impact on performance if the engine was a larger capacity. Regards, Jas. VK4FJGS Rocky Qld.

[@adarshsunil7711]

This guy never run out of ideas 😂

[@75novaguy73]

Garage54 answering all those what if questions we have. Great vid

[@adrianhoeben5783]

Thank you for this episode, I have always thought of this as a kid but have never seen it done, very entertaining keep up the good work.

[@tobythewhale]

last year my catalytic converter failed on my pontiac with a 3800v6, it had turned sideways, and when it did that I recall that the pressure backed up so much that it sounded like and old steam locomotive and would not go faster than 20-25mph and would not rev very high. the explanation from the mechanic was that the pressure was trying to escape from the engine seals itself because the exhaust pipe was blocked so badly.

[@amplify3735]

Such a valuable channel on questions that are never answered re vehicle mechanics

[@Grimm-Gaming]

Now i really wanna make a set of 8 separate 5 mm exhaust headers for a v8. But full length so u get an army of extremely angry bees out back

[@BillCut]

I was thinking similar. But more like 20mm pipes

[@Grimm-Gaming]

@@BillCut how about gatling gun exhaust but dual individual headers lol. 16 exhausts all going different directions for like a burnout car. So everyone gets the same sound no matter what

[@Jandejongjong]

Crazy how this old race barrel stil got a close exhaust system. No leaks at all.. respect to the old car being so good and solid.

[@SkyChaserCom]

You guys test the most amazing and bizarre concepts. I love it!

[@StephenTillman]

Seriously. These guys just do anything.

[@heywoodjablowme8120]

Guys like this keep the Russian military going. Just think of all the blown up tanks that are being put back together.

[@nikolakarovic5964]

Same concept Bmw give me with 320d & Dpf.

[@arcopierik3894]

This is how we made our expansion exhausts in the mid-eighties. Empty a standard exhaust, and then always mount a plate with a smaller hole on the end.In this way we could experimentally make a somewhat better (faster acceleration) exhaust than the original. They were also often better than the cheap expansion exhausts. This was for mopeds with a cylinder capacity of 50-70 cc.

[@TheRandomActivity]

How was fuel economy difference? Worse or better?

[@NerdyMeathead]

Call it the earth saver car emissions device. Sell it for 20 bucks to everyone in California and get millions in govt grants for being green. Profits!!🎉

[@snipesy]

Every youtuber ever: "Today, I'm putting a MASSIVE exhaust on my project car..." Garage 54: "ˢᵐᵃˡˡᵉʳ"

[@tomtheraton3058]

Never runs out of Idea 😂

[@flyguille]

Exaust cap diameter is not equivalent to exaust pipe diameter. A pipe of 10 will have a lot more fluid resistence than just an end cap of 10 .

[@PeaStalks]

If I had to wager a guess, I'd say the (30) smaller diameter exhaust improved velocity and helped with scavenging.

[@beatlezyt]

I love how they look like there having so much fun! 🔥

[@ImTheShepard]

This channel is just amazing.

[@gsp911]

The limiter on a Lada, is that when the valve springs can't keep up anymore? 😁

[@1987FX16]

Yeah, valve float/limiter. It's cheaper to use weak springs than to fit a computer. xD lmao Also it's hard to over rev a snap a rod when the valves slap the pistons at around 5500rpm.

[@gillespriod5509]

All carburated engines without timing modules dont have limiters, Lada engines are actually ohc and unlike pushrod old conception american "vee eit modor" engines ladas can rev easily well over 7500 without experiencing valvole float, let alone doing damage😂, with harder springs they can go 9k

[@gabrielv.4358]

Kinda, but it seems that the engine is very old too, keeping it from revving more. I mean, 6000 rpm is the limit, but the valves can probably go another 100 rpm's.

[@TwinShards]

Now we know we can install a ball bearing valve for engine braking along with a ~5mm hole to bypass the valve. This would be very useful for downhill ;)

[@rupe53]

As someone who has measured exhaust back pressure to diagnose bad cat converters in my fleet, I feel the engine starts to change quite a bit after 5 psi, although a seriously clogged converter will spike 20-30 psi on throttle jabs. The vehicle basically runs as if the fuel filter is clogged or the fuel pump (injected) is dying.

[@manfredmustermann6286]

10 mill is a tiny hole , that’s what she said 😂😂😂😂😂

[@markchapman2585]

Try a balloon on the 4 or 5 mm and see how fast it blows them up. Great video guys.

[@genehunsinger3981]

THAT'S "F"n funny!!!!

[@jameshedrick605]

I used to do that to my brothers car and he always thought it was backfiring till one day he finally seen the balloon on the tailpipe

[@LectronCircuits]

@@jameshedrick605 absolutely hilarious. Cheers!

[@dsxfab3747]

Would love to have seen a pressure gauge off the side of the tailpipe

[@rfiskillingussoftly6568]

Great video guys! Run the exhaust into the carburetor!

[@iamtheoffenderofall]

You mean make an EGR?

[@dunlie6838]

They already did in a video a while ago

[@jwalster9412]

It's not a pro changer, or a turbo, not even a supercharger, what do you call it?

[@jacksonledford6874]

@@jwalster9412 exhaust gas recirculation, many cars on the road have it today

[@jwalster9412]

@@jacksonledford6874 wouldn't also add some small level of boost to the intake?

[@ofp8574]

I'm surprised these little cars used such large diameter exhaust in the first place. Here in the US, if there were cars that small, they'd probably use about one inch pipe (25 mil.) I beleive a Slant Six Valiant uses inch and a half pipe, which is about 37 mil. I wonder if there's a big difference between a restriction in the end of the pipe versus the whole pipe being one continuous diameter. It'd be interesting to see how one of these would run if you blocked off the exhaust manifold and tapped it for a piece of fuel line.

[@t4terr]

This is real car science! Needs more attention

[@Maksimov1337]

Great way to test your manifold gasket! :D

[@venelprince6889]

also good way to blow out a perfectly good manifold gasket.

[@jasonbirch1182]

I would have liked to see a drive pressure gauge in the exhaust to see how high it got.

[@Nikkk6969]

Thanks for your English voice over man great channel 👍🏼

[@grenven]

One day Garage54 gonna be the first one to make flying cars lol

[@busyguy7479]

have to admit this is fun as always never a dull minute , wonder what could happen if u stuff a potato in the pipe ? love to see that kudos guys.

[@1987FX16]

Should have installed a 1 Bar pressure gauge to see back pressure with each size. And a crankcase pressure gauge because blowby has to be way higher.

[@DarkLinkAD]

Prob 100psi or so, prob 6 or 7 bar

[@gabrielv.4358]

yep

[@kylerenton4574]

Thanks for solving my problem!! I was trying to figure this out for so long and I just couldn't do it with my Tesla.

[@notavailable9919]

20-30 restriction while decreasing volume increases velocity which may actually improve exhaust ability, while below 20 increases velocity but not enough to compensate for restricted volume.

[@nedcrawshaw1868]

You should attach a pressure gauge on the exhaust to see what pressure the car is dealing with

[@jmptaz]

Now put a ball valve on the exhaust and see if you can use it as a brake to stop the car

[@thevalorousdong7675]

Been waiting for this!!!

[@garretfox7807]

You guys are awesome!!

[@alf3071]

maybe cars could have a valve especially designed for engine braking, you would save brake pads

[@FuckTheState]

Gasoline engines don’t need anything more than the throttle body.

[@theplayer12312]

on certain buses/semi trucks, that actually exists

[@5.43v]

​@@theplayer12312 Pacbrake

[@NicCageForPresident2024]

I love the way the Lada looks I would love to get one here in the United States. Of course I'd have to drop in some kind of a badass engine nothing too crazy but at least something that's quick

[@kevinfitzpatrick5949]

Chevy 350 swap lol. Cheap and way more power than needed for a lada

[@mikeboy337]

lada's are awful lmao. interesting but, awful.

[@d3faulted2]

Exhaust restrictions are pretty common on 2-strokes. Either the port or spark arrester plugs up. They'll start but as soon as you go to rev they fall flat on their face.

[@volvo09]

This was a good one!

[@daniellambert726]

They could have used a ball valve.

[@gordonthomson7533]

Hard to calibrate for comparison. This is chartable...if they'd actually measured any output result 😂

[@daniellambert726]

@@gordonthomson7533 Actually, given that the exhaust pipe probably has multiple leaks, I think the variable that has the most importance and impact on the engine's behavior is likely the internal pressure. That being said, I'm not a specialist, these are just suppositions :)

[@twocvbloke]

Great way to add a speed limiter.... :P

[@MDE_never_dies]

The holes started at “Ready to settle down” and ended at “Trying to find myself”

[@harlieburke3497]

I love y’all’s videos ❤❤

[@Stonet420]

My recommendation is, put a floor stopper behind the gas pedal, it will ensure you get the same results everytime. Basically put a stopper half way on the pedal, so each test you can floor it without worrying how much gas your giving it. Each test will yield a different result knowing you had the gas pedal in the same exact position as all the tests.

[@technician-tony]

Yea but he basically runs full throttle now so,

[@demil3618]

Diesel engines use exhaust brakes. So I wonder if you could fit a flap into the exhaust and see if there is usable back pressure braking as well.

[@mann_idonotreadreplies]

If ur thinking big semi trucks then NO!

[@demil3618]

@@mann_idonotreadreplies …I was thinking about fitting it to a Lada.

[@Fireship1]

Love this channel!

[@ubozkurt]

This man is the man who made all my dreams come true.

[@FHBones]

I would like to see how to smaller holes changes the cars feul consumption. Will it be better or worse? 😊

[@mann_idonotreadreplies]

wors of course.

[@willierule3744]

I would really love to know what the temperature is doing of the engine does the temperature of the engine change? Does it overheat? Does it run hot cold or cooler I mean are you would think with that all the brake pressure it would run hotter, so I’m wondering if you’re forcing the engine to overheat while you drive and how far can you drive on that thing with that little tiny hole in the engine or in the exhaust I mean

[@josh20109]

Glad to see you're still making videos, hope everything's okay for you with everything happening in the world at the moment

[@joeyf504327]

4 stroke engines do not need back-pressure. They need exhaust scavenging and velocity which is achieved through tuned resonance. Choking down the outlet changing the tuned frequency of the engine and it was obvious that the full exhaust is too big for the little engine. This is an effective method to lower HP and the red line for teenage drivers!

[@5.43v]

Let's see what the sawzall says about that

[@matthewmoore757]

At 5mm you've created a Jake-Brake. LOL!! That might be an idea for a video. Create an exhaust brake for a Lada. :)

[@joeyf504327]

no, an exhaust brake. Jake-Brake is decompression at TDC of compression stroke.

[@tOxIc_TrEaSuRe]

for breaking divert an adjustable amount (not 107%) of exhaust to an air compressor tank then blast the gasses back into the intake manifold as a compressed gas supercharger after the pedal is past half way for acceleration booste.

[@volvo09]

They should try a diy compression brake.... Just a ball valve on the exhaust, haha😂

[@David-rj6qn]

Good channel, a lot of cool videos. 😊

[@standard-carrier-wo-chan]

This is quite literally what they do in modern NASCAR to limit car power, except they do it on the air *intake,* not exhaust.

[@alf3071]

I wonder what diameter is equivalent to a dpf in a diesel engine

[@DavixDevelop]

Someone in the comments mentioned that It's 10mm.

[@nanab256]

imagine make engine where thtottle is on exhaust side xd

[@regesman7]

That would be interesting

[@gabrielv.4358]

The trottle body would melt, lol. But if it was at the tailpipes end maybe it could work

[@nanab256]

@@gabrielv.4358 egr, wastegate, exhaust throttle-it work perfectly fine on most of current engines, i dont know even one case when it melt

[@slowcarshop]

this channel is incredible

[@Universal.G]

best episode in a long time.

[@quartzcyanis]

i wonder if it would be possible to do the same thing on the intake side too

[@farvatron]

It's called a throttle bro

[@volvo09]

Yeah, that's what a throttle body is. Idle is like a 1 or 2 mil hole, and you go up from there.

[@4ri8]

What do you think a throttle body does?

[@Lacinakk]

@@volvo09 they can try it on a diesel

[@kaboooom2000uk]

Same principle as an exhaust brake on a truck. if you added a gate valve you could use it to slow down.

[@David-yy7lb]

Weld a bung at the end of the exhaust so you can put and air pressure gauge near the end on top of the tail pipe and see how much back pressure you get with each smaller hole you screw in the tail pipe

[@four20nz7]

Yes slightly restricting the exhaust builds more pressure and can actually give you a performance increase, especially if your car has VVT-I..

[@smoothbraindetainer]

That's the biggest misconception some idiots believe. No "back pressure" is good. At all.

[@JOHNKESSLER88]

Run the exhaust back to the intake and see how long it'll run.

[@mwbgaming28]

They already ran a car on exhaust gas

[@Paint0nBrush]

You could tap a pressure sensor on the capped exhaust pipe and find its maximum pressure before it stalls.

[@ashokmallappally_9600]

This guy is answering the questions of the universe 😂

[@EmDzei]

Seems you need to have dyno (dynamometer) on your garage; the 30 mm hole seems to give best result. If only motorcyclists could see this video. Here in Finland, there are a lot of motorcycles that make noise so loud that the blood literally flows from the ears when driving past them.

[@ohm1945]

? As in the percussion actually causes damage to the ears ? Surely that’d be or will be coming illegal.

[@GoldenCroc]

Larger hole and louder (less noise dampening) makes more power... within reason, If the engine is set up properly. If their 30mm made the best power, thats because something is not optimal with the engine to begin with. However, with that said, you can shrink the hole and reduce the noise quite a lot from a "straight pipe" without losing much power. The reasons many motorcyclists use loud exhaust isnt primarily because of more power, but because they like making the noise...

[@traBylliB]

After you welded the threaded piece on, you should have just used a series of reducers. I think this would result in less back pressure that you get from a flat piece of metal with a hole in it.

[@gristlevonraben]

you guys are awesome !

[@johnisabella5148]

It's possible that restricting the pipe a little could give you more torque

[@alf3071]

how does that work?

[@johnisabella5148]

@Alf if you watch dyno videos I don't know how it works but you see big upgrades in horsepower with a short downpipe, you lose horsepower with a long exhaust but somehow can gain torque

[@johnisabella5148]

@@alf3071 Steve Morris has a video that explains it a little

[@IvanOoze1990]

back pressure giving torque is a myth

[@Spike-sk7ql]

Backpressure=bad. Many guys, far smarter than me have proven it with data to back it up.

[@SocketSlinger]

Pull the car with a chain in gear and see if it will explode the muffler, destroy the engine, or slide the tires 😮. Ty love your videos.

[@5.43v]

It's hard enough to pull start them with a functional exhaust so they're gonna have to weigh it down a lot

[@Grafyte]

Keep in mind that a 4mm diameter hole has almost 2x the surface area of a 3mm hole, and a 5mm hole has almost 3x the surface area of a 3mm hole. It looks like a tiny amount of area, but multiplicatively speaking, it's a huge difference on that scale. Also 10mm diameter has less than half the surface area of a 15mm diameter, so that's also a huge difference, not to mention the 4x difference between the 5mm and 10mm.

[@bullzye101]

awesome stuff LOL .. big thumbs up

[@Homme_Pur]

that's probably making some kind of crude EGR, that's actually impressive

[@demolitionman9307]

I'd like this experiment re-tested, i'm curious on how the back pressure effects fuel efficiency. Is it possible to use exhaust restriction to save on Fuel?

[@TonicofSonic]

Intake side. Back pressure blows seals. Just drive slower and accell in the peak torque range of the engine for max efficiency.