boost problem

clubman_dan · Post by **clubman_dan** » Mon Oct 16, 2006 3:29 pm

hi everyone,
i have a problem with my car, basically the mbc is wound off completly but my standard boost controller is not in use (broken) so i am only getting about 4 psi. if i try and increase the boost at all using my mbc, it just wont hold, i increased it to the end of the yellow on the gauge, but whenever i give it any stick it will build up and then at about 3k rpm WHOOSSH it boosts up lovely before instantly dropping gradually back to about 4psi. and also if you are cruising and gun it it won't boost to the set level

its driving me up the bloody wall.
initially i thought the actuator was shagged and got one from rachel, unfortunatley its not the right one

its smaller with different mountings. but i have managed to tighten mine up now once i got over the fear of snapping the rusty manky bolt!!!
any ideas why it may be losing boost like that??
cheers
DAN

rapid R5 · Post by **rapid R5** » Wed Oct 18, 2006 12:27 am

Take actuator and bracket off turbo, drill out the 6 points that hold em together and throw actuator away, they are crap, get a proper one with two studs sticking out the back off fleabay, bolt onto your bracket.

Steve

clubman_dan · Post by **clubman_dan** » Wed Oct 18, 2006 12:53 pm

thanks for the reply mate i am going to try that today, i have a two stud 8psi one from rachel to stick on.
i want the boooooost!!!

clubman_dan · Post by **clubman_dan** » Thu Oct 19, 2006 1:42 pm

i changed the actuator yesterday, drilled the old one off its bracket and mounted the new one on there, tensioned it up and took it for a spin and it works!!
finally, i have a good solid boost!

DAN

rapid R5 · Post by **rapid R5** » Thu Oct 19, 2006 11:11 pm

Glad to hear it mate........now you just need a stronger one.

steve

rpruen · Post by **rpruen** » Fri Oct 20, 2006 8:56 pm

I have to point out that a standard actuator will hold the wastegate shut to over 25 psi. That's more than enough to overspeed the turbo to destruction.

If the actuator is broken, then it's not going to work, obviously. Fitting a working one, that is adjusted correctly, will fix the problem.

It is unlikely to hurt anything, but you don't need to spend money on one to get to 1 bar using an MBC.

Richard

clubman_dan · Post by **clubman_dan** » Fri Oct 20, 2006 10:40 pm

the mbc was already on the car! its wound off completely and the actuator is set at 8psi at the moment, don't want to break it !