the wastegate is operated by the air pressure in the intake system.
say for instance you have a 10psi WG, a small hose from a nipple mounted on the outgoing side of the compressor, is connected to the waste gate actuator. so when everything is pressurised to 10psi, its enough pressure to push open the gate, letting exhaust bypass the exhaust wheel.
a MBC is t-piece tap, that is put inbetween the nipple and WG actuator. it induces a leak.
so say you intake is at 10psi, and you have a 1psi 'leak' through the MBC, the WG sees 9 psi and stays shut, allowing the turbo to spool up past 10psi.

the 'signal' is just manifold pressure

__________________
Balls.

Yes i was told this as well - guys at Xspeed said that it leans out cylinder 4 especially. Was also told that many people run the MBC anyway and there cars are still going but it is risky and that an Electronic Boost Controller is the way to go.

WOW ! now that was exacaly what i was looking for indepth answeres, thanks guys.

so even when leaving it at stock boost it will lean out the engine ??

Removing Boost Cut from the ECU is not a good idea at all.

I had my wastegate actuator hose cut on mine and couldn't figure out what the problem was - Everytime i went WOT on 4th and 5th i'd hit cut and the car would jitter for a second which can be quite annoying and off-putting when you want to go hard.

As the WG wasn't opening as the actuator hose was cut, it was just boosting as high as it could go!

So boost cut saved my motor, it's a good failsafe thing - If you still choose to do it, at very least have a boost guage and keep a fuckin good eye on it!

__________________
[SIGPIC][/SIGPIC]
Should have bought an STI

Agreed, but by the time you buy a decent boost gauge, get it installed (defi etc) to actually accuratley monitor you boost, plus bought the MBC, you may aswel bought a decent branded EBC.

__________________
Honda Hannspree Edition CBR 600 RR - SOLD
Yamaha FZ1N - Purchased

Definitely .. I don't know too much about EBC's - I'm running Verso and is set at the ECU to 17.5psi

I've heard about eBoost2 and it looks like a decent unit?

__________________
[SIGPIC][/SIGPIC]
Should have bought an STI

well ive already got the Boost gauge

as for the EBC i dont really have 600ish bucks to throw around rite now ... well more to the point, the GF would probaly have my balls for dinner ... which might be fun ?? but the install for a MBC is easy so no cost and the hardware itself is like 100 buks max... cheap but this is the whole point of me learning more, tryin to decide if its cost effective

Dan mate, just buy one. phat bst is 2ez.

__________________
Honda Hannspree Edition CBR 600 RR - SOLD
Yamaha FZ1N - Purchased

$100 best bang (or less bang rather) for buck is an oil change

__________________
[S]kid[S]

excuse my nubness here but ...

' phat bst is 2ez ' ???