zzyx7

iTrader: (4)

Just got my mbc... tried my best at tuning the ebc, but I can either get great spool in a high gear pull, but I will overboost/spike pretty hard from high rpm shifts where the turbo is already on boil. Can't get best of both worlds, and messing with the ambient temperature changes are too annoying.

I tried the closed loop ebc algorithm in Megatune. It actually works, just not well. I couldn't get it to respond quickly enough to changes in boost buildup. Nothing but overboost and me shitting my pants, although I admit I wasn't patient enough to try giving a good tune with gains. I played with derivative a fair amount to no success, but left gain as-is.

I bought the nxs mbc off ebay for 20 bucks. Pretty simple. It has a SS ball with a fair bit of heft. Mcmaster sells ceramic ***** for pretty cheap, so I might order one up to see how that might affect the boost response of the mbc if there are boost spikes.

Laur3ns

I had my MBC in, the finally mounted my 15 PSI actuator (11-17 adjustable) from BEGI and left the EBC out.

I set it to around 17 psi it appears. I am at 14 psi < 3400rpm in 4th gear. Is there gain to be had by reinstalling MBC?

paul

iTrader: (21)

That's about what I make with my 2560 but I have a crappy 7psi actuator. I'm gonna test out the 11-17 adjustable one I ordered for my other car on it and see what it does.

Laur3ns

@paul: I had a 7psi before and was thinking high rpm boost drop off was caused by it. It think the 17psi has much better spoolup. I will probably refit the MBC to see what it does some day.

paul

iTrader: (21)

Well that certainly gets me excited. The near $100 cost for it with bracket from BEGi better give me something. Actually I bought it for my daily driver because I just swapped out the 2554 for a 2560 and the stock actuator can't be used if I clock the turbo. So I am getting one of those brackets BEGi makes that attaches to the exhaust housing so the compressor can be clocked in any direction. So if I throw this actuator on the Machine and like it it means I will need another for the daily. Damn it.

Laur3ns

Another strong vote for KISS: no EBC, no MBC, just a wastegate can that is up to it's job. I run a BEGI 12-17psi piece (probably from APT too) that results in near constant 1 bar boost.

I am going to source it postIC/preTB too maybe.

EDIT: You may see full boost 100-200rpm later, but it comes in a lot smoother and that is something my drive line will like, as do I on the track coming out of a tight corner.

I love posting replies to the wrong thread and getting a reply I was to say that I prefer wastegate actuator only now to MBC. With MBC boost climbs much more aggressively (and thus spools 100-200rpm sooner), but I prefer actuator only for now.