Hello,
Current engine has chronic coolant leak issues, injectors are toast, etc. so building up a spare over the winter to swap in the spring, but now it comes down to porting options... I've read that the 6 port aux ports close really late and are not ideal for best power or low end torque, but I'm working with what I have and seeing how it turns out.
So far the setup is:
S5 engine, RA rebuild kit w/ super seals
48 or 50mm IDA ITBs
RB 6 port manifold
4x 1000cc injectors (overkill I know but there's other plans for them in the future)
custom headers
MSD 6al ignition box
planning for a haltech 550 ecu
lighter flywheel?

Exhaust porting seems pretty standard: removing the baffle 'fins' in the insert and cut a small bit wider and higher/lower on the port to match and make it all smooth.
For intake porting, it seems like bridge on the secondary and aux ports, then small-ish street port on the center ports is the best option for all around functionality.

Any recommendations/corrections (other than "use 4 port irons")?
I've heard that cutting the bridge on a ~20 degree angle helps air flow at high rpm?
For the secondary and aux ports, do I leave them as they are and just cut the bridge and smooth out the runner, or should they be larger too (without modifying closing timing)?
Any CAD models of the ports available? I have access to a CNC mill which might help
also on a side note, if I go aftermarket flywheel, does the whole rotating assembly need to be re-balanced, or just the new flywheel and its counterweight?

Thanks in advance.

 

What are your goals for the engine? How are you using the car?

In general once you go to ITBs on the 6 port you end up having to wire the aux ports open anyway, so kiss your low end goodbye.

But if this is a track car living at 4000+ RPM then that might not be an issue.

 

Goals for power are ideally ~230hp which shouldn't be too difficult from what I've read, looking to limit revs at ~8500 or more if it seems healthy and more power up top. Car will be used as an all around car, part-time daily, and a bit of auto x and track when I find time. I've driven a few really low power cars (50 hp and just as much torque), so I don't think it'll be too bad to get used to, but if the low end power proves to be undrivable, I can adapt the ITBs on top of the stock lim and keep the aux port actuators; lengthen the intake a bit to help it on the low end.

If you aren't using the aux port actuators, do you leave the sleeves in the runner or remove them too?

Thanks