T25 housing/wheel upgrade options

[diacris]

Picked up a t25 and did a little googling to see if compressor wheels and housings could be swapped to make the efficiency of a t25 more suited for the KA's VE. From what I've read, it's a turd past 5k and over 10 psi.

I searched Zilvia but didn't find an exact match on the info I'm looking for. If there is a more specific way to find relevant threads lmk.

[s13silvia123]

most of the time this kind of stuff are trade secrets. there isn't much for you to find on the net unless you talk to a person and know them who builds turbos for a living. you can ask these guys "kinuguwa"

[1on1]

IIRC, there was a guy on here or another forum who did a t25/t28 hybrid and it achieved a higher bandwidth. He went into full detail and dynoed it but I can't find it.

[blksylv]

Does Forced Performance do an upgrade using the stock t25 housing? the BIG28?

[codyace]

The upgrade has been around forever, but it's a two step process

1: Sell working T25 so some SR boob
2: Use money to buy a used T28/GT28R/GT28RS, and the stuff to install it

[Croustibat]

Originally Posted by diacris

Picked up a t25 and did a little googling to see if compressor wheels and housings could be swapped to make the efficiency of a t25 more suited for the KA's VE. From what I've read, it's a turd past 5k and over 10 psi.

I searched Zilvia but didn't find an exact match on the info I'm looking for. If there is a more specific way to find relevant threads lmk.

It already is a turd past 10psi at 5k on the CA18 where it comes from. I have no idea why people bother installing it on an engine with 33% more displacement and hope it will be better.

Both turbine and compressor wheels and housings are too small for that displacement and that also goes for oem T28s. They will choke / overspin like crazy, just watch their compressor map and match it against the corrected airflow of the KA.

I'd say a GT28RS or even better a gt2871r A/R .84 would be somewhat well matched.

[Nissan2nr22]

I know people with T28s running full e85 and a good tune on -1820 psi external wastegate on mani etc running strong, thats something i eventually plan on trying it sounds like a real fun setup

[Jefro240]

Originally Posted by diacris

Picked up a t25 and did a little googling to see if compressor wheels and housings could be swapped to make the efficiency of a t25 more suited for the KA's VE. From what I've read, it's a turd past 5k and over 10 psi.

I looked into this years back & have actually spent quite a bit of time talking with a local turbo builder. His $0.02 on why the T25 is a turd is due to the exhaust side & internal waste gate not being able to flow enough & dump enough, fast enough. So you could port the waste gate. Port the exhaust side itself & installed a larger wheel. Ultimately, the bit of power you gain is not worth the $$$ it cost to rebuild & modify the T25. If you want to, or need to keep the T25. Weld the internal gate shut & switch to a large external gate. It'll be the cheapest route & still net you some more power.

Otherwise, GT2871r would also be my suggestion...

[240boi115]

Originally Posted by Jefro240

I looked into this years back & have actually spent quite a bit of time talking with a local turbo builder. His $0.02 on why the T25 is a turd is due to the exhaust side & internal waste gate not being able to flow enough & dump enough, fast enough. So you could port the waste gate. Port the exhaust side itself & installed a larger wheel. Ultimately, the bit of power you gain is not worth the $$$ it cost to rebuild & modify the T25. If you want to, or need to keep the T25. Weld the internal gate shut & switch to a large external gate. It'll be the cheapest route & still net you some more power.

Otherwise, GT2871r would also be my suggestion...

^^^ much agree. OP for just a little extra $$ you can get a T28 and run a decent setup.. I hope I don't get flamed for mentioning KA-T.org but they have a lot of info on boosting KA's and a lot of info on people running a similar setup.

[TheRealSy90]

Just do an external wastegate t28 setup and be done.