[sleeperstang]

Hey guys, my friend has recently purchased a car that has a pt-88 with a 6 speed, 331ci and we have been trying to get the co2 boost control to work properly and it just doesn't seen to co-operate. On gate spring (red) it makes 4-5psi smoothly in all gears. We apply 12psi dome pressure and that's where things get Wierd. It holds that 12psi pressure until the wastegate moves at which point it's as if there is a leak bleeding the dome pressure off. The boost does climb but as soon as that dome pressure bleeds off, it's going down (as one would expect it to) ... It should be said that this is the second gate we have tried (first was smaller and older so we upgraded) and its following the same characteristics. On the run I'll post up, I cheated and commanded 100% duty cycle on the boost solenoid and used the co2 regulator to achieve 14psi dome pressure to rule out the solenoid, but it still bleeds down... any thoughts?? usually in my own car my dome psi actually goes up a little as the gate opens (due to pressure difference moving the diaphragm up like a piston as the gate opens.. It certainly never drops? I don't think it takes up much volume to keep 12-14psi dome psi ?...

 

[tin basher]

sounds like a leak somewhere try spraying fittings waste gate etc
with a soap and water mix pressure it up
and look for bubbles

 

[sleeperstang]

The solid line that you see at the beginning of the run tha returns to being solid at the end of the run is the dome pressure... What bothers me is that if it was a leak in a line, it would never hold steady pressure?... it seems to happen during the actual stroke of the wastegate opening, almost like a diaphragm, but it's done this with two gates now? .... I'll bench test gate next and see.... I would think that if I'm at the 14psi solid gate psi and not desiring any change in dome pressure, that it shouldn't have to work at all unless it's leaking ?

 

[Pitbull]

I was told just the other day that they were having some issues with the Tial waste gates, its in the diaphragm.
I'm not going to say who told me but I take their word on it.

 

[Honk if parts fall off]

I hooked a leak down tester to my v60 and had 50% leakage. Put a new diapham in and it went to 15%. Took it back apart and put copper sillicone over the set screws. Waited an hour, reassembled, retested and the leak down was 0%.

 

[sleeperstang]

So I bench tested the gate today. I first applied 15psi reg pressure to the top , and then closed the bottle. It held pressure and didn't drop... I then actuated the valve using shop pressure on the lower side and went through the motions a bunch of times, in which we witnessed a pressure increase like I expected should happen, and afterwards the pressure resumed to 15psi without change... From all accounts I think it's sealing fine... the only thing left is the main co2 feed line on the car, and the solenoid (I used the wastegate lines during this test, so they are fine)... we will change the solenoid and as soon as I know, I'll post the results! Thanks guys