Why cant I set my boost at certain PSI, its max. HELP!!

[NisanS13turbo]

Ok, I have a MBC from ebay. I place it in between the wastegate and the

stock air intake and set at its furthest counter clockwiese turn but it always

goes pass 15psi on both turns. So I thought maybe my MBC must be

broken so I Got a new MBC but different

manufacturing this time and still the same. Can this be my wastegate? I

drove my car open

wastegate and boost NP so maybe its not. Am I connecting my MBC

correctly and btw my boost gauges sits about 16 vacuum. Some help

guys...thanks

[BaliLover]

If you are experiencing overboosting, you should know that MBC do have a habit of allowing boost spikes that will go beyond what you want when the turbo spools.

If you are trying to get more than 15psi with it, good luck. Every MBC I've ever played with had trouble maintaining much above 12psi

[NisanS13turbo]

If you are experiencing overboosting, you should know that MBC do have a habit of allowing boost spikes that will go beyond what you want when the turbo spools.

If you are trying to get more than 15psi with it, good luck. Every MBC I've ever played with had trouble maintaining much above 12psi

Im trying to get a lower boost not a higher boost.... and to stay steady. Is there somethign im missing here because peoples use mbc and seems fine except few like me. ANyone thats experience give the brother a hand........thanks

[Luke]

Did you say you hooked it up from the wastegate to the "intake"? It should be connected to a boost pressure source, like the hotpipe.

[NisanS13turbo]

Did you say you hooked it up from the wastegate to the "intake"? It should be connected to a boost pressure source, like the hotpipe.

Well, its hooked up to the stock rubber intake?

[Luke]

That would cause your problem then. The wastegate needs boost pressure to "push" the rod and open the wastegate flap in the turbine. Find a nipple AFTER the turbo on your intercooler piping. The wastegate needs to get a vacuum/boost charge signal. The only thing in the rubber intake tube is vacuum from the turbo sucking air through it and that's not going to open the WG.

Right now you're just allowing the turbo the spin as fast as it can which isn't very safe. Once you hook that up, the boost should be set to 7-8 psi without the boost controller.