Blackboost BOV
Recovery Vehicle
Joined: Jun 2021
Posts: 928
Likes: 866
From: Southern Florida
An increase of 8 hp in an engine that produces 395 hp, stock, comes out to 2%. I think one would be hard-pressed to notice that increase while driving. My stock P400 rips without it.
Drifting
Joined: Apr 2023
Posts: 35
Likes: 35
How do you like the miltek? Resonated? how is it in person? I’ve been wanting to get an exhaust, between the miltek and quicksilver ...
Did the intake give any additional intake noise, or diverter sound? Can you hear the supercharger at all? I could have sworn I could hear the electric supercharger in one of the videos of the intake I saw.
Did the intake give any additional intake noise, or diverter sound? Can you hear the supercharger at all? I could have sworn I could hear the electric supercharger in one of the videos of the intake I saw.
Drifting
Joined: Apr 2023
Posts: 35
Likes: 35
The intake similarly is definitely noticeable, yet subtle in "whine" when you really step on it. Casual driving don't notice a difference ...
Ladies and Gentlemen a few of us need to take a breath relax and step away from the keyboard. Your posts have been disapproved and I am hopeful we can leave it at that with no further action. Thank you in advance for your ability to adult.
Drifting
Joined: Oct 2024
Posts: 39
Likes: 20
First of all, everyone is entitled to their opinion, but no reason to hate on others. If someone you don't even know wants to put a BOV on their Defender, then why call them a 'fool'? The BOV is $200 and I don't think anyone that owns a Defender is on the poverty level where this is a huge investment.
In regards to the warranty, this is a three screw install/deinstall. If I had an engine failure that needed warranty work (regardless of whether or not it had anything to do with the BOV), I would simply remove it before taking it to the dealership and no one is the wiser.
That all being said, I bought the Blackboost BOV when I first saw this thread, but only got around to installing it today. Here is my unsolicited feedback:
I am definitely not a mechanic and my 'toolbox' is a hodgepodge of tools I've accumulated over the years. The instructions made it look super simple and I could accomplish this easily and I realized it was not. First off, the instructions are for a P400 and I have a P300 and the placement of diverter valve is nowhere near the same location. Took me way longer than I'd like to admit to find the diverter valve itself (for my P300 folks, it's basically on the opposite side corner of the P400 and in not as visible/accessible location). This became an issue in and of itself because there were hoses that were in the way of the screws and it sits deep into the engine bay. I repeat, I am not a mechanic, so I wasn't about to unplug random hoses nor do I have a fancy toolkit to with extensions necessary to make this a simple task. Had to roll up my sleeves (literally) to fit my hands/arms into the engine bay and had to feel around with my hands/tools like I was reading Braille. Nonetheless, I got the job done and should/would be able to remove it if I need to. Side note: When removing the engine cover, there were three components (the hard top cover, a thin lower cover, and a foam padding). The hard and thin covers were easily replaced, but I have no idea how the foam padding fits and just threw it my trunk. Youtube/Google were no help. Any of my P300 people know how to replace this foam padding?
On to the BOV itself. It definitely works as advertised. Extremely noticeable WHOOSH noise when I get to mid-range RPMs and left off the throttle. No Check Engine Light which is always good. The cons might just might be in my head. I feel like there is smallish lag in throttle response now and a bit more engine braking when letting off the throttle. Neither of these are major and might just be in my head.
In regards to the warranty, this is a three screw install/deinstall. If I had an engine failure that needed warranty work (regardless of whether or not it had anything to do with the BOV), I would simply remove it before taking it to the dealership and no one is the wiser.
That all being said, I bought the Blackboost BOV when I first saw this thread, but only got around to installing it today. Here is my unsolicited feedback:
I am definitely not a mechanic and my 'toolbox' is a hodgepodge of tools I've accumulated over the years. The instructions made it look super simple and I could accomplish this easily and I realized it was not. First off, the instructions are for a P400 and I have a P300 and the placement of diverter valve is nowhere near the same location. Took me way longer than I'd like to admit to find the diverter valve itself (for my P300 folks, it's basically on the opposite side corner of the P400 and in not as visible/accessible location). This became an issue in and of itself because there were hoses that were in the way of the screws and it sits deep into the engine bay. I repeat, I am not a mechanic, so I wasn't about to unplug random hoses nor do I have a fancy toolkit to with extensions necessary to make this a simple task. Had to roll up my sleeves (literally) to fit my hands/arms into the engine bay and had to feel around with my hands/tools like I was reading Braille. Nonetheless, I got the job done and should/would be able to remove it if I need to. Side note: When removing the engine cover, there were three components (the hard top cover, a thin lower cover, and a foam padding). The hard and thin covers were easily replaced, but I have no idea how the foam padding fits and just threw it my trunk. Youtube/Google were no help. Any of my P300 people know how to replace this foam padding?
On to the BOV itself. It definitely works as advertised. Extremely noticeable WHOOSH noise when I get to mid-range RPMs and left off the throttle. No Check Engine Light which is always good. The cons might just might be in my head. I feel like there is smallish lag in throttle response now and a bit more engine braking when letting off the throttle. Neither of these are major and might just be in my head.
Mudding
Joined: Aug 2022
Posts: 245
Likes: 363
From: LA
That iconic psshh might sound like your car just gained 50 horsepower, but for most street-driven turbo vehicles, a vent-to-atmosphere blow-off valve (BOV) can actually hurt performance more than it helps. Garrett Motion notes that while BOVs do protect the turbo by releasing pressure when the throttle closes, they can wreak havoc on cars equipped with mass airflow sensors. Since the electronic control unit (ECU) has already metered that air, venting it to the atmosphere leads to overly rich fuel mixtures, hesitation, stalling, and even the dreaded check engine light.
EngineLabs further explains that BOVs dump all remaining boost pressure when shifting, forcing the turbo to spool up from zero every time. This increases lag and robs throttle response, which is especially noticeable in daily driving. Bypass valves, by contrast, quietly recirculate the air back into the intake system, preserving boost and keeping drivability intact.
Unless your car is tuned specifically for it or is pushing some serious horsepower, a BOV is mostly an auditory flex. If all you're after is the noise, just know you're likely trading smooth shifts and consistent performance for a fleeting hiss and long-term annoyance. Don't be surprised if you find yourself quietly reinstalling that factory recirc valve after one too many hiccups. It may just be more beneficial to remove the muffler or resonator.
Read More: https://www.jalopnik.com/1865063/mods-make-car-slower/
EngineLabs further explains that BOVs dump all remaining boost pressure when shifting, forcing the turbo to spool up from zero every time. This increases lag and robs throttle response, which is especially noticeable in daily driving. Bypass valves, by contrast, quietly recirculate the air back into the intake system, preserving boost and keeping drivability intact.
Unless your car is tuned specifically for it or is pushing some serious horsepower, a BOV is mostly an auditory flex. If all you're after is the noise, just know you're likely trading smooth shifts and consistent performance for a fleeting hiss and long-term annoyance. Don't be surprised if you find yourself quietly reinstalling that factory recirc valve after one too many hiccups. It may just be more beneficial to remove the muffler or resonator.
Read More: https://www.jalopnik.com/1865063/mods-make-car-slower/
Three Wheeling
Joined: May 2025
Posts: 83
Likes: 26
From: South
That iconic psshh might sound like your car just gained 50 horsepower, but for most street-driven turbo vehicles, a vent-to-atmosphere blow-off valve (BOV) can actually hurt performance more than it helps. Garrett Motion notes that while BOVs do protect the turbo by releasing pressure when the throttle closes, they can wreak havoc on cars equipped with mass airflow sensors. Since the electronic control unit (ECU) has already metered that air, venting it to the atmosphere leads to overly rich fuel mixtures, hesitation, stalling, and even the dreaded check engine light.
EngineLabs further explains that BOVs dump all remaining boost pressure when shifting, forcing the turbo to spool up from zero every time. This increases lag and robs throttle response, which is especially noticeable in daily driving. Bypass valves, by contrast, quietly recirculate the air back into the intake system, preserving boost and keeping drivability intact.
Unless your car is tuned specifically for it or is pushing some serious horsepower, a BOV is mostly an auditory flex. If all you're after is the noise, just know you're likely trading smooth shifts and consistent performance for a fleeting hiss and long-term annoyance. Don't be surprised if you find yourself quietly reinstalling that factory recirc valve after one too many hiccups. It may just be more beneficial to remove the muffler or resonator.
Read More: https://www.jalopnik.com/1865063/mods-make-car-slower/
EngineLabs further explains that BOVs dump all remaining boost pressure when shifting, forcing the turbo to spool up from zero every time. This increases lag and robs throttle response, which is especially noticeable in daily driving. Bypass valves, by contrast, quietly recirculate the air back into the intake system, preserving boost and keeping drivability intact.
Unless your car is tuned specifically for it or is pushing some serious horsepower, a BOV is mostly an auditory flex. If all you're after is the noise, just know you're likely trading smooth shifts and consistent performance for a fleeting hiss and long-term annoyance. Don't be surprised if you find yourself quietly reinstalling that factory recirc valve after one too many hiccups. It may just be more beneficial to remove the muffler or resonator.
Read More: https://www.jalopnik.com/1865063/mods-make-car-slower/
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