I have heard S4 turbo manifolds and irons run in an NA mode make more power than the 6 port manifolds and housings. Is there any accepted rule as to how much more power the turbo intake manifold/irons makes on ported NA housings? (Is it 5HP or 20hp)

Currently I have an S4 ported per Mazdatrix 6 port template, running pineapple sleeves, ported turbo rotor housings and a RB header and it seems to run ok. I would like to freshen it up and throw in some used ceramics was wondering if I could do better with the 13B turbo 4 port front and rear housings and intake manifold. I don't have an turbo S4 around so I can't see how they differ. Can anyone tell me what I need to get? (or a link to someone that has)

I would guess complete harness and computer with manifold and housings.

What about air intake and filter?

Is the stock fuel pump still fine?

I have heard the S4 computer is dumb. Am I still fine here?

Do I use turbo computer? With it have a problem with no boost registering in closed loop?

Will an R-tek offer any improvement in a non-stock set up like this?

The center housing intake ports on the turbo seem bigger to start with but they don't appear to have any more meat so I am guessing the NA center housing will port out to the same size.

I did a quick search in the NA form on this and didn't find anything but I know I read some stuff on it a while back. I think YAW tried it once too. If anyone has any experience on this I would appreciate some knowledgable feedback. Thanks

 

ive been curious about it too.. im having my 6 port BP done this week and waiting to see if a s4 turbo ecu will make it run any diffrent.. dont have megasquirt yet so just gotta work with what i have. if a 4 port does make much diffrent, thatll be the next engine combo i try