Best BOV ever?!

[dubsupra209]

Bosch bypass valve from Saab. It is almost direct fit and handles plenty of boost. And best of all, dumb ricer sounds don't exist.

xxx445933983 i had the bosch great bov and only $67 i ended up giving it to my buddy cause i got a REAL greddy bov for even cheaper lol

---------- Post added at 03:13 PM ---------- Previous post was at 03:00 PM ----------

or you could get a tial...thats my next bov

 

[TurboStreetCar]

I dont understand the need for a better blow off valve to handle more boost. Most all blow off valves have a vacuum line on the side of the valve or diaphragm opposite the intercooler pipe, such as the Greddy type S and the like. With this type of valve the same pressure is on both sides of the valve. The spring tension is the only pressure differential across the valve or diaphragm no matter how much boost pressure your running. I never understood the "leaking blow off valve" issue.

 

[TooGoode]

IDK what bov you have, but mine is much too big for any parts to be interchangeable between it and the ssqv. In fact, almost every part on it but the flange is different. Unless im blind! haha

 

[MA70Snowman]

I dont understand the need for a better blow off valve to handle more boost. Most all blow off valves have a vacuum line on the side of the valve or diaphragm opposite the intercooler pipe, such as the Greddy type S and the like. With this type of valve the same pressure is on both sides of the valve. The spring tension is the only pressure differential across the valve or diaphragm no matter how much boost pressure your running. I never understood the "leaking blow off valve" issue.

"leaking BOV"
here's some excerpts for yah

"The typical point of failure on a BOV is the membrane that allows the piston to move. Either it will leak at the seal or it will rupture causing the BOV to always leak under boost. "
"Another cause of BOV leakage is the seal at the bottom of the piston. This is a temporary seal that has to break instantly and easily during pressure release yet be strong enough when closed to prevent boost leakage."

and its not so much the "need" for a better blow off valve to handle boost, its more of a BOV that can flow the required CFM to vent your intercooler piping to prevent compressor surge. sure if you're only running 8-12 PSI, all things created equal any BOV will do. but you start pushing 22-30-40 where that split second that you close the TB and the boost pressure starts surging back you need a BOV that can let off the excess pressure. I know this is BOV 101 but this leads into your spring tension. TOO MUCH spring tension and your BOV may not be opening fast enough, or might even stay shut under Low boost, too little spring tension and it won't stay closed under high vac conditions allowing unmetered air in (or unfiltered air for some)

 

[Heavy D]

my car came with a knock off ssqv, which never work and was giving turbo flutter, i thank god i had a spare turbo XS rfl from my tercel and i love how loud it is. all tho i still have the knock off just to mess around, and i also got a fake type s that works which was free, but i prefer my RFL

 

[Poodles]

IDK what bov you have, but mine is much too big for any parts to be interchangeable between it and the ssqv. In fact, almost every part on it but the flange is different. Unless im blind! haha

You're blind lol

 

[TurboStreetCar]

"leaking BOV"
here's some excerpts for yah

"The typical point of failure on a BOV is the membrane that allows the piston to move. Either it will leak at the seal or it will rupture causing the BOV to always leak under boost. "
"Another cause of BOV leakage is the seal at the bottom of the piston. This is a temporary seal that has to break instantly and easily during pressure release yet be strong enough when closed to prevent boost leakage."

and its not so much the "need" for a better blow off valve to handle boost, its more of a BOV that can flow the required CFM to vent your intercooler piping to prevent compressor surge. sure if you're only running 8-12 PSI, all things created equal any BOV will do. but you start pushing 22-30-40 where that split second that you close the TB and the boost pressure starts surging back you need a BOV that can let off the excess pressure. I know this is BOV 101 but this leads into your spring tension. TOO MUCH spring tension and your BOV may not be opening fast enough, or might even stay shut under Low boost, too little spring tension and it won't stay closed under high vac conditions allowing unmetered air in (or unfiltered air for some)

I understand the need to flow witch is why my BOV is set up to open effortlessly and whyi want to run a second BOV to ensure the air can escape quickly enough. My BOV remains cracked open at idle vacuum. Though many people think that when you run more boost you need to tighten the valve or have a stronger valve that will "hold" the boost without leaking.

 

[MA70Snowman]

I understand the need to flow witch is why my BOV is set up to open effortlessly and whyi want to run a second BOV to ensure the air can escape quickly enough. My BOV remains cracked open at idle vacuum. Though many people think that when you run more boost you need to tighten the valve or have a stronger valve that will "hold" the boost without leaking.

unfortunatly you're right, alot of people are under the misassumption that more boost = more spring pressure. X_X

TooGoode still hoping you can provide the name of that BOV

 

[super.secret.supra.club]

snowman, where is your bov located? having it too close to the turbo will also cause flutter

 

[CajunKenny]

Every MK3 I've been in has flutter. Come to think of it, most of the turbo cars I've been in have flutter. At lower boost that is...

 

[TooGoode]

unfortunatly you're right, alot of people are under the misassumption that more boost = more spring pressure. X_X

TooGoode still hoping you can provide the name of that BOV

Maybe you didn't see it, but i said it was an hks racing bov type ii. One of hks' pride and joy.

 

[Poodles]

The Racing Type II will surge on low boost as it's made for high boost apps. The SSQV's dual piston design is made to do both.

 

[dumbo]

I've read countless posts of the SSQV fluttering at low boost, myself included, and maybe one or two who claim theres doesn't. Not that that helps the OP.

 

[TurboStreetCar]

snowman, where is your bov located? having it too close to the turbo will also cause flutter

I dont see how that would work. If anything giving the air a place to escape closer to the turbo would alleviate the pressure buildup at the turbo quicker then if it were at the throttle body.

 

[GrimJack]

I dont see how that would work. If anything giving the air a place to escape closer to the turbo would alleviate the pressure buildup at the turbo quicker then if it were at the throttle body.

The amount of pipe between the turbo outlet and the BOV gives it a bit of a buffer. No pipe, no buffer.

 

[IJ.]

Had to cut down the springs in my Type 3 Turbo smarts to stop flutter with the T04z,some Turbo's have a bigger mismatch than others and are harder to shut up.

 

[MA70Snowman]

I've read countless posts of the SSQV fluttering at low boost, myself included, and maybe one or two who claim theres doesn't. Not that that helps the OP.

lol, I appreciate the concern, however I'm not looking for help. I was honestly just ranting, as was mentioned in the OP and a couple posts later. I'm not looking for a BOV, i know what I wanted and what I like. they may not be optimum but I'm aware of that. If I wanted a nicer high-end BOV, it would be synaptics. However I am quite content w/ my SSQV, I love the sound (yeah I said it), it functions great at lower boost as well as higher boost, and the knock offs are cheap and just as efficient. I was just looking for a black one (the Limited edition model) and had a adjuster on the rear to help tweak it if needed. apperantly i've found out that the HKS's newer model doesn't have that feature and neither do the knock offs.

I was wondering if anybody could point out the difference between the original HKS design and their newer one (with the "heat sink"ish fins on the sides) I got both but I haven't cracked 'em open to check the internals as one is still on the car.

and my BOV will be located on the cold side of the intercooler about a foot before my TB.

IJ i was both hoping and afraid you'd find this thread. (afraid because I half expected your post to be about a page longer full of a nice detailed and technical explanation on why I'm a total idiot because there IS such a thing as a Automatic adjusting bov) , I'm curious as to how cutting your spring would've fixed flutter. or by flutter you mean the compressor surge sound. I hear flutter and think of the sound your BOV makes at lower boost as it rapidly opens and closes.

 

[Poodles]

Nothing, just looks different.

 

[IJ.]

Most of the part throttle flutter you hear is often the spring is too stiff for the available engine vacuum to open the BoV at all as I said my 04z had stupid flutter over 10psi if you were on/off the throttle carving winding roads to the point I'd drop it back to the WG spring setting.

Took 1/3 out of each spring problem gone!

I also ran a dedicated large bore line to the 2 BoV's as this allows a strong boost signal to help keep them closed on boost.

 

[super.secret.supra.club]

also just to add. the longer the vacuum line the more flutter too.