I've been listening to videos of the Tial bovs and they all sound like my old HKS SSQV did, compressor surging. Is this a common issue? My HKS was a total pos and I'm making the switch from a 9 bov to a short route uicp and tial vta bov and just wanna make sure I'm not making the same bov mistake twice.

They wont surge if setup properly. Just make sure you have the correct spring in it for your vac at idle unless you are on SD then it wont matter. Also make sure the vac line going to the bov is dedicated and is the correct ID.

I run a Tial Q on SD and have slight surging and low boost and part throttle, but that is nothing to be worried about. Full boost surging is a lot worse and can actually cause damage. Overall, the Tial Q is awesome for holding boost and sounds cool

Yes I'm switching to speed density. I'm running a 9 turbo wide open full bolt ons and E85 so I'm thinking a 6psi spring. I know about the damage surging causes and that's what I'm trying to avoid. I'd like my turbo to last until next year (2014). It has slight shaft play already so I don't want surging.

Should be no problem then!

I would imagine the 6psi (black) spring will be too light. I like to run the unpainted spring or the yellow spring depending on displacement. I have found even the unpainted spring to open at idle on the 2.3 I just built which pulls high vacuum at idle (stock cams, stock turbo, 9:1 compression ect). On my 2.0 I believe I was running the unpainted.

So you'd recommend a 6psi spring? The car will see some street use and low boost occasionally but this setup if I get on it at all I'm way above 6psi instantly so I think that's suitable.

I have a stock block and I'll be running S2 cams and Kiggly springs, O2 dump etc.

Yea I would go with the unpainted.. Worse case you have to change the spring out, and Tial will trade springs for the cost of shipping

Good to know, thanks for the info guys. Any other input is welcome too

I would suggest the white or plain spring. You want to get the spring that matches what your vacuum reading is at idle.

You said stock turbo with cams such as S2, which will probably have around 12-16in/hg

Good luck! I still have not gotten around to swapping mine yet.

You can also PM Tial as you probably already know they're a vendor.

See I'm running Prosport gauges which are pretty accurate but I don't know what my true vacuum reading is until I install Evoscan on my new laptop. How easy are these springs to swap in and out?

If you have a boost gauge that is hooked up correctly that that should be fine to tell your vac at idle. Springs take less than 5 mins to change out.

Nice

s2 cams draw around 8-9in on my car with typical mivec and around 13-14 ign timing at idle.

Personally a tial bov does not operate smoothly in any configuration Ive seen. They're very on or off. Your BOV should not cause flutter under any condition if it is set up correctly. That means that at idle it should be light on the seat if not partially open. Those who are running the stiffer springs will lose drivability. Your blow off valve needs to be open as long as your engine is in vacuum IMHO and using a spring that only causes it to crack open on decel at any speed insnt setup properly by my standard. Thats my .02$