I work at a place that has departments that do quality control on metals so I just double checked with them before I replyied, And I’m sorry to tell you that aluminum almost any metal will fail catastrophically when pushed beyond its limits, if you had worked much with aluminum you would have noticed how easily it fractures and tends to crack also Steel / aluminum and other metals after being place through extensive thermal cycles tend to get brittle and fractures\fatigue over time.
Now I am going to ask you a question, you are using a 12 year old turbo lets say a T25, OK and its been through millions of thermal cycles ,yes its had a couple of rebuilds but the wheels have not been replaced.
Now you need more power so you increase the boost pressure to get those extra pounds of air so now the shaft speed increase from lets say 10000rpm a minute to 13000 rpm a minute the increase shaft speed is because the wastgate stays closed longer before the required pressure is reached but now because of the increase boost there is also increase heat around the exhaust house and this is made worse because of the t25 small .48 A/R step-up so now the cartage is taking more heat hence the failure of over boosted units as the seals start to give out also increased oil breakdown the turbo is also working a lot harder to produce said boost increasing the temperature of the air supplied …
Above this the tip speed and centrifugal force of the compress/expeller wheels are increase producing a more stress on the metals involved making it more likely that there will be a catastrophic failure, now lets make things worse still the t25 small .48 A/R housing will suffer from huge boost spikes even when the set pressure is reached this is because of the small wategate and the increased pressure around 3 times boost pressure between the manifold and turbo because of the incorrectly sized housing this will further more increase the shaft speed stressing the metals even more that’s why a older SR20 has a T25g with a .64 A/R exhaust housing
Now I know you are happy that you proved the blades are made from aluminum but I don’t really care, because even if they thought they where made of titanium or freaking adamantium you are still stressing them beyond the sensible capabilities secondly the increase flow of the t28 will allow it to pressurize the piping more efficiently making it more practical at the set sensible boost level but then again check the flow charts on this one.
Thirdly, I don’t care if you think the internals are the same, The “Fact” is a T28 will flow more air then a T25 that a fact unless it a special Garret unit and you can Google why.
Dude if an endless "E-thug" battle makes you feel like you have your Sx back then I’m happy I could help but this was a waste of time and it stupid stuff like this that warps the truth and stops us from helping people and that’s what a forum is for
