mbc

[4ndee]

Ok i have fitted a mbc and it wont boost above 10psi wherever i put it, i remember reading a post about it and cannot remember if you stretch the spring or cut a coil off.

[Ryan S]

Ok i have fitted a mbc and it wont boost above 10psi wherever i put it, i remember reading a post about it and cannot remember if you stretch the spring or cut a coil off.

cut and stretch, there's just too much material inside the thing.

[4ndee]

i just took it out and stretched it out and it now boosts to 12ish which will be fine for the moment

[Willenium]

I removed a very crude MBC from my brother's car earlier. When we bought it we were expecting it to be fairly loud given that it has a screamer pipe but my CT20 makes more noise. First off we discovered the pipe had come off the wastegate so it obviously wasn't opening. Secured that but it made no difference. More recently I wound the 'MBC' right open so it was basically doing nothing and still no action from the wastegate.

After pulling it off today it seems the design of the little inline device is really bad. It's got no moving parts inside, just a tapered sprung bolt that you screw in from the bottom but even then it still passes air freely.

[4ndee]

lmao drove fine today but back to 10psi, went to take the spring out to cut a coil of and it had bent down into the port to the actuator now the spring is pretty bent, so i read on the internet and apprently you can swap them for a ball point pen spring lol sure the spring rating is the same......not. but i found one and its the same length and compresses the same so ill try it tomorrow and see. Otherwise ill have to sort the old spring

[Super_red]

Cutting the spring short will reduce the spring. Stretching it, as long as you bend the metal past its elestic limit will put more spring into the spring. Until a spring is compressed its just a coil.

I found with my MBC that after dissasembly you could assemble it in such a way that the spring would seat in the thread of the bolt hole so moving the adjuster did nothing.