A front mount intercooler, blocked bov, and a pod filter will give you louder, longer doses. Metal piping cause louder and more echoing flutters than silicone piping :)
You guys understand its not bad for such a surge on a turbo fitted with anti surge housings or have a full compressor shaft. I say this because IHI turbos found in Subaru's use a hollow shaft that is prone to breaking with repeated air slamming against the compressor wheel from the opposite side
Next pay I will be trying ut one of these babies for my Evo. was always againsy it due to no real informative explanations on setting the GFB up. CHeers dude.
I always thought dose wasn't the same as true compressor surge. With true compressor surge being the turbo boosting incorrectly (e.g. Operating on the left side of the 'surge line' on the compressor map like you explained in the last video).
ndh8 it is operating above the surge line. as the air has nowhere to go (throttle is closed) the compression ratio increases greatly (y axis on a compressor map) and then stalls as the ratio is too high.
ndh8 you are correct. But so many people are dumb and always call this "compressor surge" and bash you when you try to explain otherwise, its easier to just play along.
Both are "compressor surge." The flutter when you lift your foot is just the additional compressed air escaping through the turbo. Open throttle compressor surge is the bad one, that's when you're under load and it flutters. Which is as you said, turbo boosting incorrectly. Producing more compressed air than the engine can physically take. THAT type of compressor surge is bad for the engine. Turbo flutter is not bad.
I have trouble picturing someone buying a part which sole purpose is to avoid flutter, and then set it so it flutters, even partially... but hey, to each his own i guess
It's probably easier to just set a BOV to do it rather than to remove and block off the factory BOV. Aside from that, having the BOV in place means you can switch whenever you need to.
I have a suggestion for a new video. I have a Subaru BRZ with a rotrex supercharger kit (Jackson Racing) which has a very basic bypass valve. I noticed that the other rotrex kit for my car from kraftwerks uses a proper blow off valve, a lot of guys run a turbosmart Bov on them. What difference would switching to a BOV from a bypass make?
I have the same exact BOV for my 01 Legacy, it doesn't reallyale any noise, even though it's been opened up, I'm not sure If the build up of air through the Intercooler from the turbos has any effect on it (since they both come in during different times)
I have the one before that and it's ment to be hybrid dual port full atmosphere 50/50 non adjustable but can't get it right with idle I only have the adjustment screw to go bye.
Still pretty interested in the effects on the turbo.. Pretty certain that 'the dose' wore out my 3076 VERY quickly on my stagea. But of course i assume the amount of boost you are.. surging.. is gonna make a big difference.. and the mass of the core.. tiny turbo.. probly not so bad.. big one.. probly not so good.. But also curious about stock RB25 turbo's.. because they are journal bearing..
It literally does no harm to your car. I've seen cars with 20+ psi with NO bov. It's just a myth. If you have a really, really cheap and nasty turbo, maybe it will shorten the overall lifespan. But by fuck all
He said at the end of the video that it puts extra strain on some of the components, but it's unlikely to cause failure on it's own, as people have been doing it for years without issues.
so, for turbo cars that aren't WRXs, just tighten the pre-tension screw to eliminate flutter and loosen for flutter? I have a ol' school Blitz super sound BOV from Japan
This feels like stancing your car and then liking the sound of it scraping. To each their own obviously, I can appreciate the money and effort you put into your car, but I can't help but think you're handicapping it on purpose.
Are there any benefits to compressor surge other than the noise? Rally cars seem to have a lot of surge (you always hear the flutter...) so there must be a reason why they don't run BOVs... Wear and tear obviously doesn't concern them beause a race car doens't need to last 20 years, but there must be a benefit to it for them not to dump the boost?
It slightly aids with spool, as the compressed air isn't fully expelled (like with a bov) it doesn't need to re-compress the air in the intercooler and so on. Personally I believe it gives slightly better response, but nothing major.
aaaah, yea that makes sense... I guess they figure it takes slightly less time to spool the turbo back up (because lol anti-lag) than it does to re-compress the induction plumbing. Then there's the advantage that when you step on the gas pedal, there'll be a volume of air already at the manifold for the engine to suck in. Sticking to my standard re-circ valve and a cone filter for the noise myself, but ye, TIL.
No, a boost controller manages the amount of boost the engine builds up while you're on the gas (power). Compressor surge and Dump valves are about managing how quickly you get back on boost after lifting off the gas (response). However, if someone's looking to get some more power- I'd start with a boost controller before tinkering with surge and stuff as well.
Blocking your BOV is not illegal in any way. Running an atmospheric venting bov is illegal, because they claim it puts unfiltered engine gasses into the air. Which we all know is ridiculous. But anyway, Recirc bov is fine, blocked bov or no bov is fine, atmospheric venting bov = illegal.
Depends on vehicle, Subaru ECUs freak out when you vent to atmosphere and dump fuel during shifts thinking its lean, makes loud explosions. Converting to speed density will allow you to do what ever you want to the blow off valve.
anthrax704 you won't have as much response between gears, as there is no air re-circulating ready to enter once you grab the next gear and open the throttle up
ndh8 but dont you already have air ready to grab on the inlet of the turbo? Considering you have about 14-15psi of natural pressure from the atmosphere? I thought the one and only true purpose of a BOV was to release manifold pressure and back pressure on the turbine built due to the turbine still compressing air once the throttle body is shut closed.
@@ndh8445 the recirculating air doesn't re-enter anything, as it comes out on the non pressure side anyway. If anything, no bov would have less lag due to there still being FULL pressure in the piping as it's fluttering. The whole "it recirculates air so it's ready to be taken in again" is bollocks. It comes straight back out of the air filter
Ryan Romanoski yeah I already have a block off plate in there but to be honest since I already have a response also, being able to just twist for dose is blessed instead of having to put a plate in every time
The longer your piping, or the thicker the diameter, (more space for air to fill) the louder and longer the dose will be. Having stainless piping between the turbo and filter helps a lot with the volume, and running a pod or similar filter rather than the stock air box. Even a standard wrx with a stainless/aluminium pipe from turbo to pod, will make it much louder.
Nice product placement but it'd be nice if you showed viewers other alternative methods that are free just like what the original MCM videos would have been.