Is this something I would need to have a shop do or is it pretty straightforword?

 

It's pretty easy

http://robrobinette.com/boost_controller.htm

Do not install the prespool controller. It makes adjustment very difficult.

 

Why not install the prespool? Damian did it that way with very good results. Any other reasons than just you have to tune it right?

https://www.rx7club.com/showthread.p...t=damian+boost

 

Leaving the stock prespool line alone will give you a consistent psi of 8 at transition. For many cars, this is where they should be. Installation of a prespool controller means having a 30" hose where there was a 5" hose. This longer hose causes a delay in the vaccuum getting to where it needs to be. I installed a prespool controller in my car I tried for about 6 weeks to get it adjusted properly......... without success. I would adjust one controller, then the other would be out of adjustment, and vise versa. It was a never ending problem, with no solution. I finally reinstalled the old line, and everything was fine.

If someone were considering installing the prespool line, I would suggest trying the wastegate line first, and then trying the prespool line later if unsatisfied with the results from the wastegate alone.

 

I have both the wastegate and prespool controllers on my car... yes it was a SOB to get set up right, but I still had a boost spike at transition with only one controller on the wastegate.

 

You should not have had a spike at transition with the stock prespool line. I suspsect that your prespool line was not an OEM Mazda stock line with the restrictor in it. It was probably an open hose that someone put it not realizing it needed a restrictor.

 

There was definitely a pill in it... so who knows.

But it is fixed now and works great