There's nothing wrong with T25 turbos, they're just dime a dozen. They are older tech than most things in this thread but they aren't super high trim paddle wheel dinosaurs either.
Just crunching the numbers (as gerg has) for 10psi
90% VE 1500rpm no intercooler = 7.35lb/min airflow
Dunno what your gearing is but my 2L is 2700@110kmh/70mph. Greater efficiency at cruise gets you better economy. I've assumed this is at 10psi too, it probably wont be but a big camper and all those revs could push it there.
80% VE 2700rpm = 11.76 lb/min
The 5L starts pulling fuel at 4200rpm so I've set that at the max. Doesn't really matter is your turbine is choking up if you aren't getting as much fuel. The governed limit is 5100rpm.
75% VE 4200rpm = 17.15 lb/min
MHI Turbo compressor maps use cubic metres per second instead of LBs/min so the numbers are 0.046@1500rpm 0.074@cruise 0.108@4200.
Add 10-15% to those numbers if you're intercooled.
GT2052 52trim. Good sruge margin, 77% efficiency at cruise, peak flow @10psi 19.5lb/min
GT2056 56tim. GSM, 76%, PF24
GT2259 52trim. GSM, 74%, just on peak flow
HE211. GSM, 70%, 25pf
HE221w. GSM 68%, 23.5 peak flow
HX25. GSM, 74%, 21pf
TD04-9B. GSM, 74%, just on peak flow
TD04L-13t. GSM, 75%, 0.15 peak flow
TD04-16t. Just on surge, 70% cruise, 0.18peak flow
TD04-19T. Close to sruge, 73%, 0.17pf
Those are just the compressors, turbines are another story. Out of those the GT2052 and TD04L-13T look the best, they also have suitable turbines. The 13T can come with a wide range of turbines and housings, it has more reserve flow both in terms of pressure ratio and peak flow, it's easy to upgrade to a different compressor, parts are easier to get and it's cheaper. It's the one I'd go for.
I thought 13t was the model number for the whole cartridge. Is that just the compressor? and if so, what should I be looking for turbine wise?
With MHI turbos TD04 is the family of turbos, the L, H, HL or no letter are the turbine size and the 9B/13T/16T ect are the compressor.
Gerg runs all of the boost in his high compression IDI!
Gotta go to work, talk later.