Blowoff Valves

>horsepower is irrelevant (ftfy)

Well if you put a BOV in a slow car that is making under 200hp, it's kind of like ricing your car to look like an F&F dragster even though it's completely stock under the hood and is under 200hp. You're just asking other cars on the road to embarass you.

compressor surge and wastegate flutter

not this

Another trip to filter under "fucking idiot ignore forever"

Not too many turbo cars under 200hp, unless they're diesel.

You don't even hear the wastegate on modern rally cars.

please explain how that means anti-lag makes chirping noises

WRC cars with antilag keep the turbo spooled off throttle, the chirping they make is the turbo huffing air against the closed throttle body while off throttle, and then having that pressure wave come back through the turbo. Each wave is just as loud as the turbo stays spooled from the anti lag.

On a street car the first pressure wave is the loudest, and then they peter out. How long/spaced out the chuffs are is determined by intercooler size, piping diameter, and length, as well as how big the turbo is.

You mean how it's the antilag system doing that whole chirping noise? lol
The antilag keeps the turbo spooled, the flutteringnyou hear is essentially air pressure generated by the turbo that has nowhere to go.

You can hear it perfectly in this
youtu.be/2tP7T0g0zA8?t=47

They sound cool on big, laggy turbos, and are really fucking annoying on tiny turbos that spool up in a microsecond. An Evo will only vent when you want it to, but a lot of modern cars will just constantly PSH PSH PSH PSH PSSSSHHH no matter what.

it wouldn't be making that chirping noise if there was a bov you utter twat.

stop moving the goalposts because you were wrong

Are you genuinely retarded?
Who the fuck said rally cars had bovs?

Chirping noise = antilag
Flutter noise = literally air pressure generated by the turbo that has nowhere to go if the throttle is shut

Saw a new ecoboost mustang and heard it blowing off a lot, not sure if they all do, it sounded aftermarket to me. T b h it sounded too artificial

>Chirping noise = antilag
yeah nah. just stfu

EH MISSUFIRINGU SISTEMMU

Anti lag sounds like a machine gun going off. Extra unburnt fuel dumped down the exhaust via retarding the engines timing.The explosions down the exhaust help keep the turbo spooling. The other noises you're hearing when the rally car hits the jumps is the engine bouncing off the rev limiter.

- Chirping noises are usually when a turbo car is not running a BOV and has the valve blocked off. It's air that's meant to be dumped to atmos going back against the turbo causing flutter.

-

I think what he's saying is that the chirping noise is a byproduct of the antilag, like I did in .

yeah, it's called damage control

youtube.com/watch?v=_K0LFadOKBc

I know antilag sounds like a machine gun. I was just saying that chirping noise was the result of antilag.

Exactly...
It's literally pressurised air being bounced off.
Some of it is the wastegate venting, but it's not THAT loud.

Nah, you just can't read.

You're fucking retarded m8

>ZOMG yes. Pulling away from a stop at anything other than the lightest throttle input. Pssssssht!

just add more washers/tighten the spring.

>I was just saying that chirping noise was the result of antilag.
what about when it isn't?

>zomg

Please hang yourself as soon as possible.

> tripfag
> incharge of being wrong
Just another day on the Mongolian Yert spinning board

It is. The antilag keeps the turbo spooled.
The spooling turbo keeps delivering pressurised air that is bounced off (chirping noise) and eventually the wastegate dumps the excess pressure (to prevent damage while regulating maximum pressure) so you get an additional "ssssss" noise or a light chirping noise.

>I was just saying that chirping noise was the result of antilag.
why not just say it's the result of being an internal combustion engine, or the listener not being deaf, or some other shit reason if you want to be retarded?

>you can only get sick flutters if you have anti lag
go crash your punto you silly fuck

>as if we weren't talking about rally cars
Yeah, go put a watermelon-sized turbo on your civic and enjoy your sikk wastegate sound while having your boost pressure all over the place.

WRC cars only chirp if they have the anti lag turned on. If the driver flicks the antilag switch off, it'll tsu tsu tsu just like a regular street car.

The chirping sound they make is very similar to on throttle compressor surge, as the conditions are very similar (high boost, air unable to get into engine, starts forcing back through the turbo, yet turbo still spinning at full speed, causing compressor surge), which is really hard on turbos. At the end of every stage, the first thing the driver touches is the anti lag switch to turn it off.

youtube.com/watch?v=nCj6Spwl1CU&ab_channel=synaptic1

found a video

Tuning with a BOV will improve throttle response slightly. Adjusting the spring preload gets rid of a lot of annoying venting. I've got a GFB deceptor II with an adjustable ratio of vent/recirc... I have it venting above 11psi and seems to work well. Better than the factory by pass valve which get loose as old balls...

>Friend's Mini S has 187HP and a BoV
>My Volvo C30 T5 has 230HP and no BoV
CBTs a shit, I want the douche sounds

I have an intake and a diverter valve bypass for my tsutsutsutsu noise.

It's very subtle and is only audible at peak boost, so it's very sexy.

I disagree my stock bpv leaks under higher boost levels sometimes the best upgrade is to convert to a blow through system.

theres so much misinformation in this thread it's mind numbing.

If you vent to atmosphere with a MAF based AFM you're officially retarded. No matter how much you're venting. Never vent to atmosphere if your car uses MAFs.

unless the maf is a blow-thru and placed after the bov.

retard.

Still dumb to vent to atmosphere. You can recirculate the extra air to keep the turbo spooled between shifts.

>reading mjet's posts itt

Mine leaked too so I got rid of it and welded the bung shut.

"Wastegate chatter" got me good. Better not to correct them, it's more fun that way.

It's not as much air as you think.

There's also autos and guys that use NLTS

Very little air is reintroduced. And when you are making enough boost its better to not have to worry about surge.

It's enough to cause afterburn in the exhaust and excessively rich conditions if you slap one on a stock turbo car with no other work. It's also significant enough that EFR turbos are a thing.

NLTS is neat but you still want to maintain transient response even if you aren't shifting. If you get on boost, let off the throttle, then get back on the throttle an atmospheric venting BOV is going to have worse response than a properly tuned recirculating BOV.

If you're going nuts with boost and airflow you should be moving to speed density anyways. If you're using a MAF based system the point still stands that you want to use a recirculating BOV.

>It's enough to cause afterburn in the exhaust and excessively rich conditions if you slap one on a stock turbo car with no other work

wtf are you talking about

> afterburn

Its called overrun friendo. And its not the cause. Moar fuel = cooler EGT's so you dont melt your turbo/manifold into slag.

I shoot flames out of my exhaust, MAP and MAF with a re-circulating valve.

>zomg

Compressor surge

youtube.com/watch?v=fq2ekzptguo&ab_channel=ToddLaurendet

tsu tu tu tu utut utu

Blow off valves are not needed, and are just for faggots. Do any race cars use them? No. Just another spot to get a boost leak.

Waste gate is not an interchangeable term with blow off valve...you're welcome

No, it's afterburn. Overrun refers to the coasting condition, afterburn is what happens when the rich exhaust meets outside air. It's called an afterburner in jet engines, not overrunner.

And shooting flames out of your exhaust is excessively rich. You should be targeting slightly rich mixtures for open loop but afterburn will damage your catalytic converter and exhaust.

i love my bov. ive had the car about a year and i still get on it just to hear it. i love the sound.

youtu.be/3pbUMXZvfi8

>zomg
>that pic

extremely underrated post

No shit.
You still almost don't notice the wastegate on modern rally cars.

Holy fucking shit I haven't laughed that hard all week.

OMFG tears

BOVs are okay. It's the ALS that's fucked up in a roadcar.

Doesn't have shit on the Audi IMSA GTO
youtube.com/watch?v=K7wrR42qcEg

tsuuuuuu tu tu

Is it possible to put a bov on 4 cyl diesel? I am thinking about ricing out my dads 2.0 tdi octavia

Nevermind, i found out why its impossible

>You should be targeting slightly rich mixtures for open loop but afterburn will damage your catalytic converter and exhaust.

> damage your catalytic converter and exhaust

> catalytic converter

If you live in an area that traps smog like LA or San Francisco you're literally slowly choking yourself to death from NOx, CO, and VOCs.

Stop decatting your cars.

>damage your catalytic converter and exhaust
>> catalytic converter
Glorious fireballs of freedom

The amount of additional emissions from enthuisiasts the remove cats is magnanimously dwarfed by the hundreds of thousands or millions of catted polluting vehicles on the road.

That's hardly true when your fucking car is emitting well over 10x legal limits and you're living in an area where the local geography causes a smog trap to form. Especially when every fucking "enthusiast" thinks they've found some special secret in decatting for more power.

No drop in a flood feels responsible.