My Semi-PP Intake Manifold
 

Hey guys,

Not sure if this is the right section for this but i've had a few enquiries about my intake for my semi-peripheral port engine so i figured i'd do a mini build thread showing how i went about it. I used an xcessive LIM to try and get the flow to each housing as close to parity as possible and i added in peripheral port runners that merged into the secondary runners.

For those who don't know what an Xcessive LIM looks like (where the hell have you been hiding if these people even exist?):
Engine side:
http://www.pineappleracing.com/Produ...ntake-1a-b.jpg
Strut tower side:
http://image.superstreetonline.com/f...o-xcessive-LIM

You'll notice that the engine face of the manifold has valleys (for lack of a better term) between the primary and secondary ports; the first thing i did was have these welded up and the surface faced so that it was true. After this i took to the areas between the secondary and primary ports (near the base) with a die grinder to remove the material in preperation for the peripheral port runners. From here the next step was to grab an old rotor housing and to pinpoint the centre of the hollow in relation to the centre of the stud below it to determine where i needed to mark mating surface of the manifold for drilling.

To size the holes and ultimately the p-port runners i found some tight radius aluminium bends that had a CLR (centre line radius) that would suit the distance from the LIM lower flange to the outside of the cast runners where i wanted the runners to merge in. Once i knew the outside size of the tube i was going to use i had a local shop machine a hole the same size as the ID of the tube and a lip around the edge the same size as the OD of the tube.
Like so:
http://i398.photobucket.com/albums/p...psca1d6a9d.jpg

front view (ignore my medicore porting please):
Attachment 634504
Attachment 634505

From here it was just a matter of welding some tube onto the tight radius donut halves and drilling some holes into the secondary runners at the right height and welding the runners in place. Heres the end result:
Attachment 634506

After this all that was needed was some die grinding to smooth the transitions and tape up the faces ready for powdercoating:
Attachment 634507

I didn't really think to get any decent pictures of the manifold before i installed it sadly but here's some crappy ones showing my terrible porting and not really showing enough down the runners haha:
Attachment 634508
Attachment 634509

But hey it works/braps!:
http://i398.photobucket.com/albums/p...pssh9du2tw.mp4

I ll send you mine too brad.

awsome work!

That looks great! Only question I had was how well you can tighten those lower middle mounting bolts. It looks like the weld bead would get in the way of the bolt seating flat.

I think we ground them so they they were a flat angled edge and had some spacers made up that were a matching angle for the nuts so they meshed together and pulled up nicely.

Brad.

Beautiful! Looking good! Very nice!

Motor Specs otherwise?

S4 T2 rotors
Balanced rotating assembley
CNCed rotor chamber for uniform 7.9:1 compression ratio
28mm semi peripheral ports
12.7mm stud kit
Screw in welch plugs
Rx8 rear stationary gear
Xtreme rotaries apex and corner seals
Link G4 ecu running it all; bottle neck for the car will be the T04z

That's awsome man, post up resultes when running.

Very nice. My next motor is gonna be semi pp. Then I'm gonna need this done.

Nice

Bringing this back from the dead.


any updates on project.

Same question

Latest update in November - FD-RX7 Enthusiasts Forum

not a great deal sorry guys, car made 384hp on 17psi here in aus with slipping clutch; cars getting pulled apart this weekend for install of new setrab 25 row coolers and proper ducting; i'll take some pics and throw them up here when i do over the weekend :)

Brad.

Thanks for the update. Do you think the semi pp was worth it?

Just place a larger turbo and it will make more power upstairs. That's all.