So I added a set of MBC's per robrobinette.com I have been running 17-18 vac before I added them (I could only boost to 7psi of course) and after I added these, I have it at about 9 psi and the car is measuring 16/17 with a very rare dip to 15 if the idle drops a little. Car is still smooth and runs fantastic...just the haunting thoughts that I could have done something during my couple of boost pulls...

Trev

 

i attempted to use the "home depot" boost controllers for a long time, and i could NEVER dial in 10 psi on both turbos.

i could make it do anything on the primary, but the secondary just would not work.

i was using one for the pre-spool as well, which i now think is a mistake.

 

The needle valve ones are touchy and somewhat inconsistent. The ball-spring ones, IMO, are much better.

Read these posts - lots of good info here:

https://www.rx7club.com/showpost.php...6&postcount=10

 

Maybe your boost gauge reading has shifted? Have you calibrated it?

I doubt you did any harm.

Dave

 

Well, it is a manual boost controller dave, not an electric one, so I wouldn't think any calibration is necessary. I was thinking that the needles weren't that consistent as well and I need to do ball and spring type

Trev

 

Not the controller, the gauge!

Dave

 

I meant that! So sorry man!

Trev

 

yeah the pre-spool should not be touched. if your running seq, the transition should go up as your boost goes up(ex:10-8-10, 12-10-12, 14-12-14) as you go higher though, the transtion gets harder to control

 

The car is measuring 16/17 PSI or vac?

Im assuming you're talking about vac now but i would double check your hose connections.

I also have the turboxs MBC and when i was fooling around with my intake filters, i pinched one of the lines that run from the BC to the turbo and i guess that caused the no boost (little boost) and fluctuating vac at idle.

 

IMO, running a needle valve on the prespool line is a mistake. The length of the hose makes proper adjustment nearly impossible. I suggest that you reinstall the original line (with the pill in it). Running a single needle valve on the wastegate line will give you good flexibility of adjustment, and good results.

Regarding idle vacuum, don't worry about it