Hey all,

I have a Tial QR on my stock turbo X. I get tons of compressor flutter and on the highway the car is very jerky. On Decel my car hits 22-24 in/hg and at warm idle it's at 20 in/hg. I run 30psi, daily. At wot, things are fine. But anything below that I get quite a bit of flutter.

I have a "Pink" or -11PSI spring in it.

What spring should I choose (Or do you run) that could possibly alleviate these issues?

-Alex

 

Years ago AMS did something with one of the mut scan tools to fix this problem for me if I remember correctly?

 

Tial says
-18 and -21 in/Hg Un-painted -11 Psi (-22 in/Hg )

So you have the right spring...what's your idle set to, stock rpm? Also, there isn't much adjusting with the tial, just switching springs out....so you might check to make sure the vacuum port isn't kinked, or make sure there isn't a crack in it or something.

 

Softer psi spring.

 

Ditto, get the -8 psi spring.

You have pink, that's -11, unpainted is -10, I'd personally go with the white spring, ie -8 (-16 in/Hg )

Chart from Tial:

Engine Vacuum Reading / Color Use Spring
Between:
- 22 and -23 in/Hg -12 Psi (-24 in/Hg )
- 20 and -21 in/Hg Pink -11 Psi (-22 in/Hg )
- 16 and -19 in/Hg Un-painted -10 Psi (-20 in/Hg )
- 12 and -15 in/Hg White -8 Psi (-16 in/Hg )
- 8 and -11 in/Hg Black -6 Psi (-12 in/Hg )

 

Then you leak at idle...which is probably okay since it's recirc. I'd say it's worth a shot if your vacuum source is known to be good and of a proper diameter and not collapsed.

 

I also had horrible flutter at part throttle 15-20 psi where the car wanted to rocket past to 25+ psi. Made tracking the car on a road course challenging and I had to adobt a more on/off pedal approach and kiss finesse goodbye... Swapping from an 11 psi spring to 8 psi helped but it was still there. Reducing my MIVEC agressiveness at 180+ load helped abit as well. Probably the biggest issue was the GTX30 turbo has a rather large compressor flow capacity compared to it's exhaust side so once you hit that 3500+ range it really wants to just go full boost.

On paper the Tial QR looks perfect but I had poor luck with it. Might be fine for WOT driving at a drag strip but daily driving and road course driving it was barely passable.