When I accelerate at WOT my boost shoots up to 1.4bar but then quickly drops down to 1.0bar and stays there until the next gear and then does the same thing next gear. I have a Hallman MBC and I just installed HKS 272 cams, cam gears and Dynoflash. Im not really sure what would cause this much drop in boost. Any ideas?

Thanks

 

What do you have your Hallman set to? Also which way did you hook it up? Just about all the MBC will have a slight drop of about 1-2psi in the upper rpm's no matter you set it at.
Try installing it with one side going to vacumn (BOV t-in line) source and other to the waste gate actuator in two Evo's I have seen set up this way have had no problems.

 

Also when you installed the MBC did you plug off the remaining stock locations?

 

Yeah thats the way I have the MBC installed. I have had the MBC for a couple months now and I just noticed the large boost drop off after installing the cams. I readjusted the MBC for the cams but I cant figure out how the cams or the Dynoflash would effect the boost this way.

 

Sounds strange I would try to give Al a call and see what he thinks it might be. I had a friend who hat a similar problem and it ended up being the two little clips under the hood for the stock snorkle where gone and it was sucking up against the hood. Do you still have stock airbox and if so you might wanna check that?

 

what are they gears set to? also is there any driveablitiy issues with the car, does it feel like it misses at idle? could possibly be an overlap issue, who installed the cams?

 

Good luck Reignman. Hope you get it fixed soon

 

I have a cone filter (took out stock airbox). Right now my cam gears are set at 0/0. I havent adjusted them yet. I installed the cams myself and the car seems to pull very hard so I was surprised to see the boost dropping that low.

 

double check the cam timing, make sure everythings lined up, also most people are having to switch to the stiffer spring on the hallman boost controler, did you? turn it all the way closed then give it 2 full turns, that should be a start then adjust from there. i dont think the dyno flash has a thing to do with it, its the cam install or the mbc.