Quick MBC Question

[guitarXgeek]

I'm in the process of making a MBC using a needle valve. I know the stock hose is like 3/16", right? However, the valve I'm using has 1/8" thread holes for the hose barbs, and the hose barbs are 1/8" thread and 1/4" nipple, and the vacuum hose that I have is 1/4". Are all the sizes I'm using ok? Will this be ok with the 1/4" vacuum hose or do I absolutely HAVE to use 3/16"? Thanks!

 

[skippydog21]

As long as it is snug on the car and the mbc i dont see any poblems. We have made them before at home depot and just bought some spring clamps to make sure they dont pop off. Personnally the homemade one never made me feel very secure. I just spent the 50 bucks and bought one. I feel more at ease of not overboosting due to my lil home contraption not working right.

 

[Defiant]

A needle-valve MBC is not recommended. You would be much better-off with a ball-and-spring MBC.

 

[guitarXgeek]

What's wrong with the needle valve, Defiant? A couple of guys around here are using them for MBC's, and are having no problems whatsoever. Enlighten me!

 

[Defiant]

Let me try one simple thing, first, yet again:
No bumping threads.

Now, then.

A ball-and-spring, once open, will have a variable, pressure-driven and self-regulating control orifice. More boost, more opening, more wastegate opening, less engine death.

A needle valve will only have a very narrow range of operational adjustment. If there's a mistake, you can get runaway boost. Not as good.