Ported oem intake manifold
 

Anyone ever fully ported the oem manifold ? I recently did mine and was just wondering if there was anyone else that have done this and what kind of gains did they make ? currently at 225 on my ap1 and hoping to make close to 235-240 with new ported manifold and larger throttle bodyhttps://cimg5.ibsrv.net/gimg/www.s2k...31825d911d.jpg
https://cimg6.ibsrv.net/gimg/www.s2k...f3fde34ee2.jpg
https://cimg7.ibsrv.net/gimg/www.s2k...8418c8ec86.jpg

interesting, please post results as I have a spare manifold laying around and getting tuned soon!

will do hoping to have it installed this week. Just a quick heads up if you plan on swapping out the manifold yourself its not fun to do at all lol.

+12 hp is my guess :)

Bumping an old thread since its been a while. When I installed the manifold unfortunately the porter had cut too deep into the IACV and I had an internal vacuum leak. Fortunately enough I found SBS performance and luckily enough he had prior work done to these manifolds. The leak was fixed and now going to have it installed along with a 3.5 inch intake to see what kind of gains it makes. Here are some update pics of how the manifold looks now
https://cimg1.ibsrv.net/gimg/www.s2k...732b435a21.jpg
https://cimg3.ibsrv.net/gimg/www.s2k...ee767b8cf3.jpg
https://cimg0.ibsrv.net/gimg/www.s2k...50250df844.jpg
https://cimg2.ibsrv.net/gimg/www.s2k...4219ef6062.jpg

Sub'd for content, Alot of power is on tap with airflow in and out, with these cars its a matter of taking an already engineered proven set up and giving it another notch or two up.
much like the rx8, I feel you wont see much unless everything else is brought up, might even lose power (torque) down low

I know these aren't like the k series motor where the more air the better, but with such an optimum motor and design already im sure opening it up even more should help out some. Im currently at 226/156 with just a simple intake,header,exhaust setup on e85 so looking for some good substantial gains from the new intake hardware im installing

For sure, Im interested to see what's the real world outcome, might even do the same ;)
back when NA subaru's where still cool for rally-x and autox i had my 25rs intake ported and flow matched and it helped alot with tuning as number 4 wasnt constantly running lean.

Yea i come from the k series world and so far its been a learning curve with this car. But hopefully this works to my favor.

If you are na then I hope the runners weren't enlarged as they are already too big. Having gone thrifty the work the plenum should have been enlarged at the same time