few notes-

Forge valves have been hit or miss for us, I dont like their boost controllers though-

Turbosmart- their valves seem to corrode and then they dont seat properly- I DO however really like their Wastegates-

The Tial (I have seen VERY few recirc valves) acts in a very abrupt manner in my opinion- It's very touchy especially at part throttle lift and back on throttle modulation in road race conditions-

I only really use Tial VTA valves- and ONLY in Speed Density conditions- on cars with larger than stock frame turbos- that arent building alot of boost part throttle or under light load-

----------

as for the other plot above- I do remember changing the valve- I DO believe it was retuned around the upgraded valve- but there was less knock present up top even at higher boost because of the turbo not having to work as hard-

Again-

there are variables to alot of these valves/conditions- I was simply stating checking these things is a very important part of building turbocharged vehicles-

My recommendation to other shops- keep a known good valve on hand- when the car is on the dyno swap the current valve for the known good one and see what happens---- generally- you find an improvement-

also-

Jeff Perrin (a good friend of ours) has offered to send me one of his BOV's to test- Last time he sent us something to test- (his intake for the stock housing turbos)- we were blown away by the results- we will see how this goes

Cheers

CB

 

Very nice to see quantifiable improvements on something like this... Going synapse myself

 

Anyone have troubles with a Greddy Type RS BOV?

 

Do a boost leak test and confirm your suspicion

 

You still have't answered my question on why you believe testing your car above 20psi is dangerous.

 

sorry-

well mainly you have a few things going on-

the main one- the fear of a tech blowing his face off with the pressure tester LOL! (alot of the aftermarket turbos dont have the lip machined into the compressor cover inlet- so the pressure tester cant get a good overall grab on the cover-)



cb

 

Ha....so true. I've done that a few times myself...


-Bink

 

Interesting read. I'm planning on giving the Cobb a try on my X since it's working so well for Scheides, but I do look forward to your test results on the Perrin since the guy who bought my IX ended up installing a Perrin on it.

 

Well I hope he isn't putting his face right up to the tester. Luckily both my tester and the stock turbo has a lip so I can test 30psi. I have found parts to leak at 25psi and above that weren't at 20psi so this is why I ask. My crushed stock IX valve leaked after 26psi and would have lost power without me knowing it if I were to only test up to 20psi.

 

If you post your issues on turbosmarts website on the page for the product you bought they are pretty good about responding.

I had an issue with my wife's dualport on her STi and I had to turn it almost full stiff for it to hold boost in the upper RPM's. You should try that.

 

good info, and kudos to you for doing a pressure test when dyno'ing cars. I think that is a great idea!

 

Very informative. Glad I read through this.

 

I've seen the same thing. Boost pressure always changes with BOV's.

I had a Greddy Type S, but the diaphragm is a consumable and expensive and difficult to find. It had poor part throttle response as well. Then I went to a Forge RS, horrible part throttle, made the car undrivable at the track (road course). Now I have an APS, and it rulez, perfect driving at part throttle and no leaks.

 

A lot of the TiALs I've seen are knockoffs, just like CBRD said about the Greddys. It's unfortunate when someone gets ripped off like that

 

Ashame aps dropped the US Evo bov market