After market Turbo adjustment....

[Twebs]

I need help! I don't know what I should have this adjustment at and what's safe to have it at. I tried to find out on google but came up short.... The knob says "TURBOXs" on it and has a + and - that turns, not sure what each notch means and what it is safe to have it at. It was in the car when I got it and I bumped it one day and I'm not sure what it should be at....

 

[7M4EVR]

Just a manual boost controller. Do you have a boost gauge or are you using the stock one? If you want to you can open it up all the way so it is just like there is nothing there and it will run at stock boost. To turn boost up you turn it the opposite direction so it closes off and allows less air through, this lets air bypass the wastegate spring and increases the boost. As for how much boost you can run safely depends on alot of things, specifically the health of your motor, and the AFR's. The safe bet if the motor is healthy is to get a wideband and monitor the AFR's. The risky bet is start turning up the boost until just before you hit fuel cut. I wouldn't advise the later. Are you on the stock headgasket, and fuel system?

If you are worried about it you can just take it out and run a line from the wastegate to the turbo housing outlet nipple and run stock boost levels all day.

 

[AbsoluteSpeed]

Turn it all the way down (to the -).
If you want to increase boost turn it up a little and go for a drive to see what psi it reaches. Keep adjusting it a little at a time until you reach the boost level you are after but be careful. More boost causes more issues and like 7M4EVR said, if you can not monitor the AFR's you could do serious damage.

Just a manual boost controller. Do you have a boost gauge or are you using the stock one? If you want to you can open it up all the way so it is just like there is nothing there and it will run at stock boost. To turn boost up you turn it the opposite direction so it closes off and allows less air through, this lets air bypass the wastegate spring and increases the boost. As for how much boost you can run safely depends on alot of things, specifically the health of your motor, and the AFR's. The safe bet if the motor is healthy is to get a wideband and monitor the AFR's. The risky bet is start turning up the boost until just before you hit fuel cut. I wouldn't advise the later. Are you on the stock headgasket, and fuel system?

If you are worried about it you can just take it out and run a line from the wastegate to the turbo housing outlet nipple and run stock boost levels all day.

First time I red your post I thought you were telling him to turn it all the way up. I was like "NOOOOOOOO!!" Lol
I must be tired.

 

[Twebs]

Ok so what I'm understanding is that I can turn it all the way down and run stock boost.... That's what I'm going to do! I got the car in December just for a winter project and I'm planning on selling it, I just replaced the carpet and some of the leather, the engine runs great I just was afraid of that knob! Thanks so much!

 

[chevyguyjoe]

First time I red your post I thought you were telling him to turn it all the way up. I was like "NOOOOOOOO!!" Lol
I must be tired.

He kinda did. A manual boost controller is a bleed valve. All the way closed will give you stock boost. When you open it it bleeds boost out into the atomsphere from that little line going to the wastegate, so there is less boost at the wastegate. As long as OP follows the plus and minus, he will be fine.

 

[7M4EVR]

He kinda did. A manual boost controller is a bleed valve. All the way closed will give you stock boost. When you open it it bleeds boost out into the atomsphere from that little line going to the wastegate, so there is less boost at the wastegate. As long as OP follows the plus and minus, he will be fine.

(Lil John voice) WHHAAT?!

1.) A MBC CAN be a bleeder type- Yep, im with ya
2.) All the way closed will give u stock boost? Umm you lost me...Go pinch ur line from outlet nipple to WG closed with some vicegrips and tell me what happens
3.) All the way open will bleed off boost to atmosphere and create less boost- all the way open will be just like there is no mbc there and will run at stock boost.

Think of it this way...your wastegate is closed, it needs a certain amount of air to open it, opening it allows exhaust to bypass the turbine and lowers boost. So if you leave the wg closed your turbo just keeps on a spooling faster and faster. You allow more air to get to the wastegate and it pushes open the wg and regulates boost. Sooooo opening the mbc all the way lets more air in and regulates the boost. Closing the mbc more and more increases boost by letting the wg see less air.

(Lil John voice again) OOOKAAY?

 

[chevyguyjoe]

This is how ive understood it: If the mbc is all the way open its like unhooking the line from the wastegate. It sees no boost, so the turbo keeps spooling. There is a check valve in the mbc that closes under vacuum so there is no vacuum leak.

Of course all my knowledge on this comes from the internet, so i may be way off.

 

[hvyman]

There is a ball and a spring. The more you tighten the stiffer the spring. Air is also bled off to help bypass it some. Only a very small amount should be bled off.