I have a 89 S5 with a S5 Tii JDM swap done with:

- 3" intake piping
- FCD
- 2.5" Racing Beat dp
- Hi-flow 2.5" racing cat
- N1 Apex'i muffler
- All 2.5" straight exhaust inbetween

Peak boost is 9.5psi, and by redline is about 7psi.

Am I still in danger of boost creap or overboost, and would it still be wise to port my wastegate?

 

If peak boost is only 9.5.psi then I'm not sure why you're worried. Unless you plan on fitting a bigger exhaust you don't need to do anything.

 

S5 turbos dont really boost creep at all, especially not with a 2.5 inch downpipe.

 

haha, I'm worried because people on the forums are worried. And no, I do not plan on upgrading anything till I go standalone (just looking out for my engine and trying not to blow it ). I'm actually going to work on the handling part of the car more for now.

 

well, If you have some downtime and want peace of mind, you should go ahead and port it.

It only take a couple hours for pull/port/reinstall and it will make you feel better

just my thought

 

I would port it. With those mods on a cold night in 3rd or 4th gear I would be a little worried.

 

you should definetly get a bigger fuel pump in there if you are hitting 9.5psi regularly. I mean you are safe right there but borderline with the stock pump. If I were you I'd pick up a walbro 255 and be on with it.

 

Oh sorry I didnt mention this, I have other mods done to the car; like the Walbro 255, HKS ssqv.

 

If it's staying below 10psi (even on cold nights) and you already have an upgraded fuel pump then you have nothing to worry about.