Hey guys tried searching the internet before posting a topic but I here people have to pull timing if they are hitting more than 17ish lbs of boost with the portfueler? Why is that? I have 8.8 compression btw dont know if that matters. Thanks guys.

IIRC, The stock computer only does so much, the Higher you go in boost,the more your figthing the OEM ecu, as its advancing you i belive to compensate for what it thinks is right for a NA. it doesnt know what your trying to do. Effectivly it doesnt do good things with your tune because its a chaning variable. Most go with Crane or MSD ignition to controll timing. Typical rule of thumb is 15psi on a s20g. some get away with more, some dont. If your wanting to go that high, a MS system might be a better fit for you.

But as long as my afr is ok than its fine or no? Ive also heard it will start to knock I have the 16g at about 15lbs and it sounds ok.

No, AFR being OK is independant (not totally) of Timing. You could have an 11.5 AFR at WOT, and have a timing issue. Thats why we rule of thumb it. When we we tuning MS, AFR was where we wanted it , but we were listening for any signs of det or knock, that would tell us we needed to adjust our timing map.
Id sya you are safe if your not hearing knock, but thats not to say it not happeing at a slight level.

Make a Det Can and drive around or go on a dyno and listen for knock. I believe the stock ECU stops correcting timing for knock after 14psi.

Originally posted by Gruff511
Make a Det Can and drive around or go on a dyno and listen for knock. I believe the stock ECU stops correcting timing for knock after 14psi.

What basis are you making this statement? The stock ECU has no idea what boost level you are at.

That's what I always thought. Before I went standalone people told me about the stock ecu and 14psi thing, that's what made me want MS in the first place. This was back in Team-2g.com days.

If you want to avoid the complexity of a MSD, you can try water injection and go up a few more PSI. I don't speak from experience (yet) but this used to be an avenue some people used successfully.