Blow Off Valve vs No Blow Off Valve | Sound and Science
202,509
Published 2022-05-10
The car in this video is 2Broke2Boosted, my budget turbo Mazda Miata. This car is running an eBay, HKS knock off blow off valve that's been installed for the life of the turbo setup (since 2020). You can see more of this car on my channel!
Full build parts list available here: tinyurl.com/5a3ksb8k
End Screen Music: 3mbrace - Issues spoti.fi/3hpG1b0
*All links are affiliate links, purchasing through them means a small portion of the total cost goes towards supporting the channel, and there's NO additional cost to you! CashedOutCars is NOT liable for any damage done as a result of videos posted on this channel. Work on and modify your car at your own risk!
All Comments (21)
-
Flutter all the way!!! Great comparison, so many people demonize no BOV like "you're gonna blow the turbo instantly", but you weren't biased, thanks for that.
-
I did oil analysis after running BOV vs no BOV on a journal bearing turbo and saw copper wear levels after the no BOV and return to normal after running the BOV again. I'd be concerned about the axial wear on bearings if you're on a journal bearing turbo, if you're running a ball bearing turbo, I believe the bearings are more tolerant to axial forces. Otherwise have fun with the cool flutter! Now, I will mention this is on a 480whp STI running about 28 psi on speed density. On lower boost applications it's not going to affect it as much.
-
I have an atmospheric diverter valve and i get the BOV sound at certain rpms and a flutter at other rpms, best of both worlds sound wise.
-
Good explanation! I weld, fab and tune right out of my home garage, I cannot stress this stuff enough to "car guys" with big egos. They always think what Joe Schmoe said on a forum 20 years ago is total truth. I'll start using this video for them. I ran without one for quite some time, loved the flutter and it was tuned for it. Added a TurboXS RFL for a change up. Beyond noises, I did have issues with high boost and couplers coming off without the BOV, but that was only a couple van-gen clamps of a problem. Great video!
-
sweet video. “blow off valve” was said 358 times
-
I rarely ever like videos, but this was exactly what I was looking for, appreciate the video👍 I swapped from 1 50mm BOV to 2 forge diverters & haven’t done the vacuum lines for them yet, I like this because you showed what it does without vacuum to the BOV & justified my decrease in boost pressure for now👍
-
Thanks for explaining what a BOV does and how it works
-
Which sound do you prefer? Want to visualize air exiting out of the turbo? See this video! https://youtu.be/NbvCpH7dJNs
-
How are you not at a million subscribers. I havnt been here since the beginning but I’ve been here since 10k and I’m amazed at how much your video quality has increased. Your awesome please keep at it
-
it sounds so cool without the vacuum line disconnected
-
I ran a BOV on my 93 XR-2 (a front wheel drive MX-5) and I had no problems. That car had the old school barn door MAF and I had no problems.
-
I really like both sounds, but I think I'd pick w/BOV hissing/breath sounds over flutter personally.
-
Have no bov on my car and it loves it sounds so good, been playing with some different length intake tubes to tune the flutter sound 🙃
-
Love the video. Building a twin turbo 347 in my mustang and still learning alot as this is my first turbo build. Thanks man.
-
Great explanations.
-
The information provided about everything with a bov on is correct, however some of the information with the BOV disconnected is just a bit off and car specific. Id recommend revisiting or relooking into this with a different style bov or possibly a more modern vehicle.
-
BOV sounds sick
-
Building a boosted RHD Accord wagon!! Thinking flutter for me 😊
-
I’ve been running mine with blow off valve disconnected for around 6 months. Haven’t noticed any leakage out of the flyin Miata/turbo smart bov with just line disconnected
-
Great info thank you
