Fastbird

And I'm underwhelmed. I was actually able to put them in pretty easy since the BOV's sit right where the front brake ducts were (APS Kit) so I could just reach in there and remove the bosch valves.

The Turbosmart Kompact 25mm Dual Port valves came with a pink -14 to -24 In/Hg spring. I have the caps backed off as far as I'm comfortable with, they're VTA on the horn side and capped on the recirc side, and I'm only barely hearing them after I make a 10+ psi blast and snapping the throttle shut spiking the vacuum. I think I'm going to need to spend the money on the lighter green springs. My car, according to the Pillar gauge and the Eboost2 controller, shows ~20 In/Hg vacuum at idle.

I didn't notice any flutter, but I sure as heck didn't spend nearly $300 for the same sound I had before. More to come.

dougrodriguez

Lol I noticed the same thing on my aps setup. I'm on tial recirculation at the moment but I'll switch to my 50mm atmosphere ones once I figure out what to do with the intakes flapping loosely and see if i can hear it better then the Bosch or my tial recirculation

inspector12

I tried to tell you. Recirculation isn't going to sound too different no mater what valves your using.

ajrothm

As long as it's venting efficiently to prevent compressor surge, what is the issue with the sound? Trying to ricer it up? Try the HKS Super Sequential BOVs and put the trumpets on em.. That will get you turbo civic/neon sound you're looking for.

BLOWNBLUEZ06

Fastbird

Mine was two fold. I was getting some flutter with the bosch valves, indicating a slow and not long enough reaction. Wanted to alleviate that, and if I got more sound, no biggie. Try telling EnglandGreen his is ricered up with the huge race bypass valve vid he posted a few years ago. A by product of venting a lot of compressed air is sound and I expected more sound than what the bosch valves were giving me by proxy. Unfortunately after making more adjustments yesterday and paying close attention I'm still getting the flutter on a slow reaction which is going to necessitate a spring change on the new ones. Besides, if you've ever held a cheap plastic bosch valve you know you want something better in there.

I'm VTA btw. Haven't been recirculated since the kit was on the stock motor.

BLOWNBLUEZ06

How do you have the vacuum/pressure lines connected?
I can tell you that each should have a 1/4" line directly back to the intake manifold. If you're reading that and saying "vacuum is vacuum", I understand and thought the same thing. With my triple Tials and F2 procharger, I had a bad surge when beating on the car WOT. I had come off the brake booster line to a distribution block and then off that block to another downstream block and then to a third manifold right at the 3 BOV's to distribute to them. I was advised to make a straight shot back to the manifold with each and it would cure the issue. I made one small exception. I put one large 5/8ID hose into the intake, dedicated to a manifold with 3 outputs, going to the BOV's. Problem solved.

Fastbird

I'll have to trace them, it's been so long. I know there's not a large manifold but they may be sharing a port together that's teed into another line. That's the most I remember. I'll report back when I have done that, but it'll be a couple of days as I'm on a 3 day work stretch starting today.

ajrothm

On my Z06, I have 3 Tial 50mm BOVs, Ofcourse it's a supercharged setup so it works different then the turbo setups, they stay open all the time and are RIDICULOUSLY loud all the time.....it's annoying as hell... But it keeps blower belts intact.

On my turbo bike, I have a single Tial 50 that's tied to the plenum. There is no vacuum on the BOV at idle so it stays closed at idle and normal riding, under boost the BOV gets pressure applied to keep it closed, chopping the throttle while in boost get it an instant reaction and a quick whoosh! Operates plenty fast with the standard TIAL 50mm spring.


Tie the BOV in as close to the intake as you can, that prevents it from seeing vacuum at idle/low load situations, that way it stays closed in normal operation.

Even quick bursts of boost and quick chops of throttle will dump it fast thru the BOV.. You'll hear it but it won't be crazy annoying.

If you want the loud chirp when it blows off(ricer style), get the HKS SSQ. The Tial BOVs are the most reliable and fast acting, they will yank open quick.