“Dial a boost”

[DARTHV6]

I have this on my car I’ve never used. Some people call it “Dial a gasket” because it’s easy to turn up too much boost and blow a head gasket. Does anyone know which way you turn and what a half turn is equivalent to how much boost?
Thanks,
Art

 

[Turbo6inKY]

Typically unscrewing it will reduce the preload on the spring, which makes it bypass sooner, and lower the boost setting. Screwing it in will increase the spring pre-load, raise the pressure where it opens, and increase boost.

How much you get per turn of the dial is completely dependent on your car's particular setup. Test carefully. Move it in smalls steps until you know how it behaves.

 

[DARTHV6]

Typically unscrewing it will reduce the preload on the spring, which makes it bypass sooner, and lower the boost setting. Screwing it in will increase the spring pre-load, raise the pressure where it opens, and increase boost.

How much you get per turn of the dial is completely dependent on your car's particular setup. Test carefully. Move it in smalls steps until you know how it behaves.

Thanks, kinda thought so

 

[87GNALKY]

Thanks, kinda thought so

KY is correct. Usually, one turn is 1# and 1 right turn is up (from 21 to 22), hence 1 left turn is down. Just watch your logging software as mechanical parts are off a bit usually.

 

[87GNALKY]

KY is correct. Usually, one turn is 1# and 1 right turn is up (from 21 to 22), hence 1 left turn is down. Just watch your logging software as mechanical parts are off a bit usually.

My bad, I thought you had the factory spring. Didn't notice the photo. The dial types usually have click points and I am unsure how much each click represents on those. Good luck.

 

[rag231]

It doesnt look like it has anything connected on the other side to me. It doesnt look like it regulating anything. You might have yourself a big ol' vacuum leak. No telling what your fuel pressure is or what your boost maybe sitting at. Make sure that there isn't a line dangling free somewhere before you take it out for a spin and blow a head gasket or something. If I'm not seeing the pic correctly or thats how that thing is supposed to be plumbed and function like a bleed off valve or something, I stand corrected. If it is completely closed, then its non functional, that's my first guess. Maybe someone had it hooked up at one time and during troubleshooting , bypassed it and just turned the knob close because there werent another vacuum line to connect to it. DarthV6 do you have the TurboBuick 101 basic boost and fuel pressure gauge on your car?

 

[1986 Buick GX1]

It might be the glorified aquarium valve.
If it’s tee’d into the stock boost solenoid or tee’d into a hose running from the compressor housing to the wastegate actuator, opening the valve will bleed boost to atmosphere.

With it closed, the wastegate actuator opens at 15 psi boost so that’s what the engine sees.

When you open the valve to let 5 psi boost bleed to atmosphere, the wastegate actuator still opens at 15 psi boost.

The engine sees the 15 psi boost from the actuator plus the 5 psi boost going to atmosphere for a grand total of 20 psi boost.

If you could post some photos of how it’s plumbed, that should help determine what type of boost controller you have.

 

[turb0buick57]

Had one of those on my car when I first bought it years ago. I would just make 1/2 turn adjustments until I got the boost where I wanted it.

Sent from my LG-H900 using Tapatalk

 

[DARTHV6]

It might be the glorified aquarium valve.
If it’s tee’d into the stock boost solenoid or tee’d into a hose running from the compressor housing to the wastegate actuator, opening the valve will bleed boost to atmosphere.

With it closed, the wastegate actuator opens at 15 psi boost so that’s what the engine sees.

When you open the valve to let 5 psi boost bleed to atmosphere, the wastegate actuator still opens at 15 psi boost.

The engine sees the 15 psi boost from the actuator plus the 5 psi boost going to atmosphere for a grand total of 20 psi boost.

If you could post some photos of how it’s plumbed, that should help determine what type of boost controller you have.

I think it is a glorified aquarium valve. Must turned it a pinch to find out...carefully. Thanks!
Art

 

[DARTHV6]

Had one of those on my car when I first bought it years ago. I would just make 1/2 turn adjustments until I got the boost where I wanted it.

Sent from my LG-H900 using Tapatalk

Exactly!

 

[ttypewhite]

There is no set increment for turning that dial to get a certain boost pressure. Take it off the car and close the valve completely. You will notice you can't blow through it. Continue to blow through it as you turn the dial. Once you can start feeling your breath blow through the other side, that's when what ever is set at your wastegate rod will increase. So start from there and make small turns on the dial and watch your boost. 17 to 18 psi would be max on pump gas with the right octane.