Blow Off Valve Question

Started by s12det · Jan 30, 2010 · 22postsSMF 2010–26

s12detJan 30, 2010, 8:55 pm · #1

i have seen some people on other sites not using bovs. why would people do that? i would think its not safe due to compressor surge. anyway my question is i have youtubed sound clips of bovs to see what im gonna like and i have notice alot of the bovs are right by the turbo...now i know when i turbo'd hondas i always ran them before the intake mani. so where does everyone run them on there ca18det's?

turbos12Jan 30, 2010, 9:14 pm · #2

i have mine by the turbo

s12detJan 30, 2010, 10:03 pm · #3

i guess my question is there a difference does it help at all?. or is it prefrence?

turbos12Jan 30, 2010, 10:26 pm · #4

im not sure..i put mine there cuz im running a blow thru mass air flow setup..and the maf has to be after the bov

KeithJan 31, 2010, 12:05 am · #5

s12deti guess my question is there a difference does it help at all?. or is it prefrence?

A lot of people put them by the turbo because there is more room there.

The ideal place is by the throttle body, for quicker response time. The vent noise is typically louder if placed closer to the turbo.
All-and-all, I don't think it really matters much where it is located.

Here's mine....

posted image

IggyEGuanaJan 31, 2010, 1:03 am · #6

nearest the TB is "proper" because faster response time and it reduces the turbo re-spool time (turbo doesnt have to refill as much of the charged air path)

mine
posted image

s12detJan 31, 2010, 2:23 am · #7

ok thanks guys....iggy your engine bay is extremley clean....any good photos of the bay at different anglesand such? does it have a wire tuck?

IggyEGuanaJan 31, 2010, 6:45 am · #8

thx. the link to my garage thread is in my sig. Its mostly tucked except for the engine harness that u can see there. didnt feel like goin all out and runnin it off the back of the head and down through the firewall where u cant see. too much work as it was

for ur bov dont get a DSM one like i got. it sucks at both function and sound. sounds like a weak sneeze lol

sideways_s12Jan 31, 2010, 9:50 am · #9

it actually sounds pretty good on your car it's just not loud enough lol if it was louder it would be siiick.

DraconisJan 31, 2010, 10:37 am · #10

I've used bovs all the time. Often times though, it is not in sight and hidden so that the piping is clean as in hidden or upside down so not visible yet closer to the TB as Iggy stated.

s12detJan 31, 2010, 6:06 pm · #11

i have used dsm before and hated them. i actually bought a blitz off a member on here.

ArroJan 31, 2010, 8:05 pm · #12

s12deti have used dsm before and hated them. i actually bought a blitz off a member on here.

Yeah but, no offense, you seem more concerned with sound than performance. I've run with DSM BOV's, Blitz Super Sound gen 1 and 2, GReddy Type-S, and some generic Turbosmart knockoff.

The design of the BOV determines both airflow and response. The DSM is the best bang for the buck, because it opens fast, flows a decent amount of air, and doesn't suck balls. The upgrade from that would be the GReddy Type-S, which is designed almost exactly the same as the DSM, only with more airflow and it's rebuildable/cleanable. Both the GReddy and DSM BOV's feature the "quick-release" vent, which supplies boost to the underside of the diaphragm to help defeat the spring quicker. The DSM's is non-adjustable or controllable because it is cast into the housing, although you can modify it to control it. The GReddy has a little hose barb for that, and you can connect or disconnect it at will.

Blitz is "OK" but you can't disassemble them as much as you can the GReddy unit. HKS is good but PRICEY, way more money than you need to spend. The big daddy of all BOV's is the TiAL which flows the MOST air.

BUT the real issue here is plumbing. If you're running an air flow meter, you really should be plumbing the BOV BACK into the intake because that air is metered. The nice thing about the DSM and the GReddy is that they can be run both ways.

And anyways, the quick-release feature found on the DSM and GReddy BOV's is only found on those. If you aren't running mega-big boost, you want that quick-release feature.

KeithFeb 1, 2010, 12:13 am · #13

Arro The nice thing about the DSM and the GReddy is that they can be run both ways.

The HKS ssqv's can be run both ways too

ArroFeb 1, 2010, 12:28 am · #14

Yup, forgot about that. You get what you pay for lol.

KeithFeb 1, 2010, 12:36 am · #15

ArroYup, forgot about that. You get what you pay for lol.

Free at christmas time. Thats when I got mine..about 8-9 years ago

I think the re-circ adapter was like $15

LyniumFeb 1, 2010, 1:36 am · #16

turbos12im not sure..i put mine there cuz im running a blow thru mass air flow setup..and the maf has to be after the bov

if you did a re-circ setup it wouldnt matter where the BOV is so much... maybe.. no wait.

The the reason the bov has to be before the maf is because the BOV dumps the air to atmosphere. So otherwise it would be dumping already metered air. In such a manner, it would still add fuel to compensate for the air that gets forced in, and has no way of knowing you just dumped it out before it made its way into the engine.

With this setup however, you should be able to plant a cone or whatever you like filter right on the intake of the turbo.

In general, as i've seen, You would have the Maf before the turbo and everything else.
This would have all the air coming in metered. And theoreticaly you'd have an intercooler.

You would want to do the re-circ method, with the blow off after the IC, going back in between the MAF and turbo, keeping the turbo spoooled slightly quicker and keeping the metered air in.

Also, you'd want the signal/boost/vac line to the blow off relatively close to the throttle plate for quicker response.

IggyEGuanathx. the link to my garage thread is in my sig. Its mostly tucked except for the engine harness that u can see there. didnt feel like goin all out and runnin it off the back of the head and down through the firewall where u cant see. too much work as it was

for ur bov dont get a DSM one like i got. it sucks at both function and sound. sounds like a weak sneeze lol

I had a 91 talon with a re-circ.. I hated it...

As for cars without a BOV.. my XR4Ti doesnt have one. it goes straight form the turbo, over the valve cover, into the intake.

No BOV, no IC, no nothing...

When I first got it, I stood there and stared at it for like an hour dumb founded.
I was always scared of it thinking in my mnd it should grenade any second... of course one car had 170K km on it, the other like 230K km on it or so.. soo.. I dunno.

just a waste gate on the turbos and go for broke.. ?

ArroFeb 1, 2010, 5:28 pm · #17

LyniumWhen I first got it, I stood there and stared at it for like an hour dumb founded.
I was always scared of it thinking in my mnd it should grenade any second... of course one car had 170K km on it, the other like 230K km on it or so.. soo.. I dunno.

just a waste gate on the turbos and go for broke.. ?

That's how a manufacturer saves money. And why 80's turbocars all ended up with blown turbos by the mid-90's. Cheaping out. BOV isn't just for performance, it's for surge protection to extend the life of the turbo.

And intercoolers extend the life of the engine. Most these manufacturers that skipped intercoolers ran 7-10psi and pig rich, and only needed it to last the warranty period a majority percentage of the time. We however are looking towards performance and reliability. Run a BOV. Run an IC. Even modern turbocars come from the factory with both now.

/thread

blue streakFeb 2, 2010, 1:06 am · #18

Yeah, I'm running a HKS just past the turbo. And basically recirculating back into the turbo. posted image

mod_mastazFeb 2, 2010, 1:46 am · #19

Well since everyone else is posting pictures of their engine bays...

posted image

Evo8 BOV(near the airbox)!

ArroFeb 2, 2010, 3:03 am · #20

Yeah Hung's (mod mastas) BOV setup is IMO one of the slickest.

blue streakFeb 3, 2010, 1:15 am · #21

ArroYeah Hung's (mod mastas) BOV setup is IMO one of the slickest.

Yes, very nice!!

pukkaSILVIAFeb 17, 2010, 7:41 pm · #22

nice engine bay Keith