It seems with both intake and exhaust being side ports, that it would give you some freedom to time the PP in and out and help minimize the overlap.

What causes the 13B-MSP to not be a common swap given its much newer and could possibly be more flexible? I know that for basic porting its too close to the jackets for the MSP's, but if you went full PP wouldnt it be a much newer rotary system to work from?

 

You would want to use the 4 port 13B-MSP just like you use the 4 port 13Bs so you don't have the aux port wear on the side seals and imbalance of the rotor seal gas blow down pushing the rotors to one side.

Still you have the early opening stock intake ports on the 13B-MSP which aren't side seal friendly.

The 4 port motors don't come with the good 13B-MSP stat gears though, so you would have to source those as well.

Probably want to use the 13B GSL-SE rotor housings so you only have to machine the peripheral intake ports and not exhaust too- otherwise the machining will cost more than twice as much.

Probably don't want to use the 13B-MSP rotors as they have a shallow apex seal groove that you would have to machine to use normal 13B carbon or ceramic apex seals.

You could try using 13B-MSP ceramic apex seals in a p-port- I don't know if anyone has done this.

Additionally the bevels on the rotor edge don't anything in a p-port motor except make an additional cold spot in combustion and the rotors aren't balanced at all from the factory, so a bit more work balancing them.

13B-MSP 6 port E-shaft, stat gears, bearings, oil pump should all be good for a p-port motor though.

 

Minimizing the overlap of any PP virtually makes the PP useless. If there isn't enough scavaging from the exhaust side, your essentially loosing the vacuum that's needed to pull the intake charge through the PP.

 

the power in the 13b-MSP is in its complex intake manifold system, likes 2 steps above the s5 NA so its like basically a constant variable runner intake which is controlled by the computer.

Adaptronic now has a replacement ECU which could work for the engine outside of the vehicle because the ECU is pretty entangled into the vehicle architecture.

 

Minimizing the overlap is an emissions related optimization... it helps light load misfires and stuff. It's irrelevant for any race engine of a sufficient caliber that you're peripheral porting the intake. The newer stationary gears are nice and the eccentric shaft is good too though, but past that you'd have to figure out some way to seal the exhaust ports in the irons and then why not just use the older stuff with fewer holes to fill?

 

Right. I guess that was the thing, for the cost of adding some devcon to a few more ports, you have some freedom on the exhaust PP, as well as 9k RPM stock internals and all the other improvements the RX8 got, and newer easier to find parts (At least talking nowadays)

 

I am extremely skeptical of the idea of devcon surviving exhaust ports is the thing. It's just epoxy.

 

Hell, it doesn't last particularly long in INTAKE ports.

 

Unless you like to waste money then don't waste your time too.