Just want to give props to Perrin on taking these EBCS's to another level and designing changes for real world use.
I recently started tunning my JDM STI ver 8 longblock swap. I have full intake and exhaust mods and the JDM Twinscroll(VF37) was spiking like crazy. Stock Subaru Twinscrolls have a rep of spiking after you open things up exhaust and intake wise.
My tuner suggested we upgrade the boost control or go MBC(
). I had spotted this thread months before and liked what I read. So I ordered one through Import Image, and a few weeks later I installed it and started tuning again.
Before I was trying to hit 20-22psi and it would spike 25+ to the point of fuel cut. Scary on a 5000 dollar new setup.
After the Perrin, my tuner sent me a new map with lower duty cycles etc. Within a few revisions we were Hitting full boost 20-21 psi by 3400 rpm(AVCS FTW) and now no more spike nice and smooth. I may have some logs I can dig up showing the difference.
Install was easy, only my unit came with the universal mount and not the one that is 02-03WRX specific. But I still was able to mount it in the stock location with the universal bracket so no big deal there. One thing that concerned me was that the metal solenoid started to spin in the plastic case when tightening the nipples in. It did not seem to effect the final outcome in any way. Another thing I want to mention is that the instructions state you are not to block the exhaust port on the solenoid in any way, but I thought it wouldn't hurt to plumb the port like stock is back into the intake inlet and it seems to work perfect. It is a little louder in cold weather(kinda clicks), but that may be from the mount or just the price you pay for better boost control.
All in all great product!! Fast interrupt is the way to go, car pulls like a champ and boost lands where you want it to.\
Buy the Perrin, I stand behind it..