if i port the mani, port turbo & fit better O2
will the gain that is potentially free if D.I.Y'd be as much as fitting a 10.5 housing to my stock 8 turbo?
while the porting maybe free its quite some work while a 10.5 housing is like $180
and easily fitted will the porting be worth it?

 

Cheapest and most effective way to attack this is to port the exhaust manifold and get a larger O2 housing. Which will free up a lot of back pressure. Porting the hotside does not produce a lot of extra power. Coating does help but cast items retain a lot of heat and would only be highly recommended for tubular or stainless steel items like the ebay O2 housing.

 

I´d say that it might be best to step up from your current unported 9.8 housing to a fully ported 10.5 housing. Of course, at the same time, while you´re there, go to a tubular O2 and port the exhaust manifold, as well.

 

almost as good as having a stock ix turbo on stock mani and stock O2 then?

 

not quite lee,i've tried both,the ix turbo will flow more due to the compressor and the 80 series tubby with the right set of cams will give more torgue and better top end than the 8mr turbo for instanse,the only turbo that can matche is torque or so i believe is the 71gt turbo,but it will fall short on the top end and it cannot take as much boost as the 80 series one,but gains are 20 bhp in between the two, and 30 between the 8mr and the 80 series,my stock mani is ported as well along with rest of the parts that can be ported ,turbo hotside,t/b,inlet mani

 

At low boost levels (about 20 or less) i would say it should be better than a stock 9. In average the 9 turbo start to make more power at boost levels above 20 psi.