I recently went back to a single turbo.

Question:

I only run one boost pressure and have no intention of changing it.
I have the wastegate spring set so that I am seeing about 15.5 PSI.

I do have a new Profec B Spec II hooked up right now. However, I was messing around with it tonight, and it is kind of confusing with the different settings available. Boost %, Gain%, Start boost%, etc..

FYI, I lowered the spring tension on the wastegate before I started to mess with the Profec.

Does the boost controller offer any other perks other than being able to adjust the boost in the car. Boost response?spool up? etc.. I didnt notice it much, if it did.

What do you guys use. Controller or wastegate spring???

Thanks

 

A boost controller should help spool the turbo faster because it can hold the wastegate shut right up until your target pressure (or roughly so -- I am sure it starts to open a little sooner so it doesn't overshoot the target). With spring pressure, the wastegate starts to open sooner letting some exhaust out that could otherwise be used to spin the turbo. I think Sport Compact Car magazine did a test of a bunch of boost controllers a while back, including some simple ones. I am not sure if they tested without a boost controller, though. They had graphs of boost versus RPM that might be interesting to look at. I believe they also tested a ball and spring type controller, which is an inexpensive and relatively simple alternative to the electronic offerings that still performs pretty well.

-Max

 

Profec B Spec II isn't that hard to set up either. Set Boost sets your solenoid duty cycle for the amount of boost you want to run.

The 'gain' setting will determing how stable your boost by rapidly opening and closing the WG.

The 'start boost' setting is how long your WG will remain closed before your target boost. The longer you can keep the WG closed, the quicker your spool and the faster you hit target boost.