Tial 38mm boost control problems

[Coup D E'Tat]

I have a Tial 38mm, 1.1bar "HP" spring, and a Joe P. MBC, which I put a stiffer spring into a little while back. I'm trying to find the original spring just to try it, but I don't think it'll work.

With the MBC going to the side port, and the top vented, I have zero boost control. With the assembly so loose the ball is rattling around, it wouldn't go below 21 or so PSI (as estimated through DSMLink and verified on my gauge.) Turning the spring down did increase boost, though. I just realized that this is why my boost fluctuated so badly on some of my old logs.

Since the 60-1 died, I put the 14b back on, wastegate flapper welded shut. I tried the Tial method, and it'll hold 14-15 PSI easily (which seems strange) but won't increase at all, regardless of spring tension.

Am I missing something simple here?

 

[BumpinTalon]

Yeah... boost controller runs to the top port on the Tial, not the side port.

 

[Coup D E'Tat]

Yeah... boost controller runs to the top port on the Tial, not the side port.

Since when?

The problem seems to be fixed using a softer spring.

 

[BumpinTalon]

Since when?

The problem seems to be fixed using a softer spring.

Since TiAL said so

http://www.tialsport.com/documents/w3_tial_wginstall.pdf

"Wastegate Air Control top port connection vent to atmosphere or add air for adjustable boost control"

 

[clipise]

Since TiAL said so

http://www.tialsport.com/documents/w3_tial_wginstall.pdf

"Wastegate Air Control top port connection vent to atmosphere or add air for adjustable boost control"

.

 

[Coup D E'Tat]

Try again. The side port has to see pressure. Adding the ball/spring MBC before this delays the opening of the gate.

 

[RavenX]

I also have a 38mm tial and i use the side port as well. From what i understand you only use the top port when you have a electronic boost controller like the Greddy Type S etc.