TiAL 50mm BOV spring

I'm running a 11psi spring as well but I use to run a 7. Cant hear the 11 at all like I could with the 7.
 
I'm also running this bov, but don't know what spring is in it since I didn't install it. Why did you guys choose the 11psi spring? Does that mean it will only discharge anything over 11psi?
 
I'm also running this bov, but don't know what spring is in it since I didn't install it. Why did you guys choose the 11psi spring? Does that mean it will only discharge anything over 11psi?

Its all based on idle vacuum... Go to TiALs website... They have a chart handy... On my mobile phone now or I would post a link
 
It has to do with the engine vaccum pressure. Or at least thats what I read. I use to have a 7 psi spring and my car ran like crap, always stalled and had a very low idle.
 
Its all based on idle vacuum... Go to TiALs website... They have a chart handy... On my mobile phone now or I would post a link

here you go...
Engine Vacuum Reading / Color Use Spring
Between:
- 22 and -23 in/Hg Pink -12 Psi (-24 in/Hg )
-18 and -21 in/Hg Un-painted -11 Psi (-22 in/Hg )
- 14 and -17 in/Hg White -9 Psi (-18 in/Hg )
-10 and -13 in/Hg Black -7 Psi (-14 in/Hg )

my engine vacuum is between 16-17 at idle... i have the white 9psi spring
 
Thanks! I did see that on their site. I have 9-10psi of vacuum at idle, so according to this I should run a 7psi spring? Either way whatever is in the car seems to be working great as long as a run a good amount of boost, say over 10psi, which I always do. If I'm crusing and roll in and let out of the throttle under low boost it doesn't blow off, so I hear some shudder back through the turbo.
 
Thanks! I did see that on their site. I have 9-10psi of vacuum at idle, so according to this I should run a 7psi spring? Either way whatever is in the car seems to be working great as long as a run a good amount of boost, say over 10psi, which I always do. If I'm crusing and roll in and let out of the throttle under low boost it doesn't blow off, so I hear some shudder back through the turbo.

Do you have a big cam??? idle vacuum seems kinda low. Whats your block learn [BLM] look like?:confused:
 
here is the method we have started using after installing 5 or 6 of these,
take a stiff spring like 11psi or so and install on car, crank and let it settle to a hot idle, look at the bov see if its open, we take them and cut one ring off the spring at a time until its barely open at idle, then with it hot and running rev it up from under the hood and make sure it closes when close to no vacuum, this way works for us on all of our cars. with the spring being to weak it takes positive pressure(boost) before it will close all the way, therefore causing the car to cough or sputter between the vacuum to boost transition. don't get scared we have cut a spring so far down its the length of a valve spring but it works flawlessly. no hesitation or compresser surge. if you feel like you are getting close to right start cutting a 1/4 of a ring at a time.

ps: this is all on speed density cars(no MAF) but if you got the tial its going to atmosphere anyways
 
here is the method we have started using after installing 5 or 6 of these,
take a stiff spring like 11psi or so and install on car, crank and let it settle to a hot idle, look at the bov see if its open, we take them and cut one ring off the spring at a time until its barely open at idle, then with it hot and running rev it up from under the hood and make sure it closes when close to no vacuum, this way works for us on all of our cars. with the spring being to weak it takes positive pressure(boost) before it will close all the way, therefore causing the car to cough or sputter between the vacuum to boost transition. don't get scared we have cut a spring so far down its the length of a valve spring but it works flawlessly. no hesitation or compresser surge. if you feel like you are getting close to right start cutting a 1/4 of a ring at a time.

ps: this is all on speed density cars(no MAF) but if you got the tial its going to atmosphere anyways

great tips! I have an extra stiff spring to try this on, thanks.

tial makes an Alpha Q is a recirculating valve. Donny Wang from DRW posted on it after installing one for a customer of his. The tial Q is the atmosphere exiting and Alpha Q is recirculating, both are brand new this year, its only their 2nd generation after years in the business. their stuff works, period.
 
Great forum subject. I have always wondered how these things work. I had an ATR BOV at one time and never thought it worked at all. tha nks.
Conrad
Hot Air
 
i would think try keeping it closed barely because when you let off under full boost you get more vac for a few seconds so that should jerk it open coupled with the positive pressure on the underside of the bov and the vac on top of it.
 
Leaky BOV?

If you guys have it in park and are under the hood and you rev it, does it pop open when you let off? I do have the -11psi spring and -17inHg vacuum at warm idle, but when I rev it in park and lift, it shoots to -21inHg and pulls the BOV open. I'm chasing high BLMs at idle when in open loop and really want to make sure this isn't the problem.
 
tialsport tech should chim in!

he's here on the board but I dont know how often.

this would be a PERFECT subject to discuss.

the park or drive is what I am wondering but I am sure its idle.
 
Bov spring

11 pound spring should be plenty for 17" vac in drive. I have 19-20 in park and 17 in drive and actually had to cut half a coil on 11 pound spring to get it dialed in perfect. if you rev engine and chop the throttle it will open about 1/8" for a second then close. if you think it is the cause of high blm's, just unhook vacumn line to bov and see if blm's are still high. Another thing to check is the o-ring that actually seals the valve. with vacumn unhooked spray o-ring area with starting fluid and see if rpm's jump up. If they do o-ring is your problem.
 
Does your o-ring seal all the way in the sealing surface or can you see part of it? When mine is closed, I can still see like half of the o-ring all the way around. I'll take pics and post them tonight if I'm not clear on what I mean.

My high blms are only at idle. During cruise they're 123-126, so things are fine there. I'm wondering if it's cracking open when I pull up to a stop, driving the blms up, then the chip switches to open loop idle with the high blms, causing me to be rich.
 
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