Ok so basically I am running a drag gen 3 kit on a stock b18b which was recently street tuned with Hondata to the stock 5psi External Tial Wastegate spring. My tuner set the boost cut off at 7psi. I've had a Turboxs mbc laying around so I decided to throw it in and turn up the boost by a pound or so. However, the boost controller fluctuates like crazy. Before I put the BC in, I was running 5psi on the button. Now, I have the BC installed and turned all the way closed (fully clockwise) and its reading between 6-7psi. Now I wouldnt care about this if the boost cut off was a little higher but when I rev to 6k in second gear I hit the cut off and my CEL flashes and I loose all power. However, in third gear, it stops dead at 6psi obviously w/o boost cut off. I dont get it....shouldnt I be running 5psi when the boost controller is all the way closed? I dunno if I should just take the controller out until I get the car on the dyno and change the cut off. Anyone else experiencing inaccuracy with this boost controller or is it just b/c im attempting to adjust it by such a small amount above the stock spring setting? Also, is it dangerous for the car to hit the boost cutoff?

Thanks for any help

 

I had a turbo xs MBC for a while and couldn't get it to hold steady so I sold it.

 

It might not really be the MBC....it might be the exhaust manifold you are using.

 

its the bc, typical symptons of it, i have one just like that, never could have constant boost, and boost changes if the temperature was different

 

I got the same problem, except its around 14psi and hit boost cut In the market for a stable electronic one, lookin at the turbosmart.

 

i have the blitz sbc-id, its a little more expensive, but the best one i've used so far