MBC test?

[herostar]

Hello everyone in DSM world!
I just made my very own MBC for my car, but I am not 100% I did it correct... I followed the instructions online and it all looks right. I guess what I am really asking is if there is a way to test it before I put it on my car to make sure it doesn't fu(k up on me. any help is welcome

 

[Bohrn]

not really. But you can take a bike pump with a good guage in it and see if it works that way. Then put it on the car and drive it real easy!! Trust me on this. And take any tools you need to adjust it with ya on your test drive.

I'd suggest setting it so that the adjusting screw just barely touches the top ball(or the spring, depending on your design). Then you most likely won't overboost.

Take the car for a rip, but pay attention to the boost guage!! Go somewhere that you can do 100mph, as your car will do that in 3rd gear at redline. And 1st/second gear is not enough load for long enough to see if you have it set properly. you must do passes in 3rd gear, WOT to redline.

Take it easy, take your time, and make sure you have the space to do this safely.

 

[nine5raptor]

open it up nearly all the way and blow on the positive boost side, you should be able to blow through it until you tighten it down enough to engage the spring, start tuning with it there. I used an air compressor with a line regulator and had it open at 13 psi before putting mine on the car.

 

[nine5raptor]

in terms of the tools for adjusting...I used a wingnut for my jamnut, I don't have to have anything to adjust my boost; you guys should try it too.

 

[Bohrn]

good idea with the wingnut.

 

[herostar]

I tried bowing on it like nine5raptor said, and I can adjust it like that, but it is either I can blow through it, or I cant, I cant get it to go to where it opens and closes... any Ideas? I used a spring out of a pen, it's a medium/soft spring rate...

 

[Bohrn]

probably too soft. It can bind up. Use a spring that is stiff enough, but not so stiff as to be too hard to adjust.

again, just do like I said, and drive it easy, then test it out.

You'll get it.

 

[LaserRST]

This is what I did since I work at a tire shop. I got a used valve stem and took the rubber off the bottom so there is nothing but brass. Connected a hose to it and to the boost side of the MBC and aired it up. As long as it isnt leaking it should be extremely precise. Mine holds 16psi and did exactly that in my car.

 

[nine5raptor]

a pen spring is entirely too weak...when it stops and you can't blow through it at all it is because the spring is fully compressed and the coils are resting on each other. go to a hardware store and buy like 10 dif. springs of varying strengths. find one that is just a little too strong and cut coils off 1/2 to 1 at a time to adjust. just make sure you bend the ends to make a good perch for the bb and the adjusting screw.

 

[Bohrn]

yep, the part about making the end of the spring compatible with the ball bearing is right. Its gotta fit nice, and be level.

 

[turboedoutlaser]

hook it up and see if it works ,

Bill N @ www.extremetuners.com