Modified stock turbos???

[btustison]

I remember someone talking about having stock t25 turbos modified for better top end flow, it might have been Dee. Anyway my dad is trying to find an affordable turbo for his daily driven Miata (1.8) and I was hoping to get some more info on what mods are being done. I appreciate any help.

[Sil40sK]

I personally have the exhaust housing ported rather lightly and slowly tappering down to stock size by the time it reaches the wheel and it seems to help with top end a little bit without effect spool up time. I don't know what else could be done though, prehaps a new compressor housing or center section combo, then you'll probubly run into fittment issues. I don't know though. For the Miata you'd probubly be fine with an SR T25 cranked to like 9psi. Just nmy 2cents though

[boost_boy]

I remember someone talking about having stock t25 turbos modified for better top end flow, it might have been Dee. Anyway my dad is trying to find an affordable turbo for his daily driven Miata (1.8) and I was hoping to get some more info on what mods are being done. I appreciate any help.

Yeah, it was me that used the modified T25 which basically became a T2/T3 (funky T28) using both your housings. The front housing got bored for fitment of the bigger wheel and the back housing also go machined for the bigger wheel. The fun part about this over the .86 housing of an S15 turbo or the .64 housing of the SR T25s is that you get to keep the wicked-fast spoolability while gaining some efficiency up to 21psi of boost. It's claim to fame or sweet spot was at or around 18psi.

Dee

[c-rad]

Yeah, it was me that used the modified T25 which basically became a T2/T3 (funky T28) using both your housings. The front housing got bored for fitment of the bigger wheel and the back housing also go machined for the bigger wheel. The fun part about this over the .86 housing of an S15 turbo or the .64 housing of the SR T25s is that you get to keep the wicked-fast spoolability while gaining some efficiency up to 21psi of boost. It's claim to fame or sweet spot was at or around 18psi.

Dee

S14/15 uses a .64 back housing... only the GTiR had a .86 Even though that's not the real point of your post...

[btustison]

Thanks for the help guys.

[boost_boy]

S14/15 uses a .64 back housing... only the GTiR had a .86 Even though that's not the real point of your post...

You're right! It was late when I posted that. What in the hell was I thinking? Ahhh yes "Sleep" . And you'll never here me speak of a gtir anything, so correction like c-rad said, S15 turbo uses 0.64 rear housing, not 0.86.

Dee

[dbody1]

Dee,

I am in the process of having my stock t25 rebuilt when i read this post.Can you give me more details on the modified turbo your using ( wheel size) and any other details thanks for all your help.

Bruce

[boost_boy]

Dee,

I am in the process of having my stock t25 rebuilt when i read this post.Can you give me more details on the modified turbo your using ( wheel size) and any other details thanks for all your help.

Bruce

Bruce, though I haven't had a turbo like this in over 3 years, the mod basically had T3 wheels in a T25 housing that was bored. Don't remember much else, only the fact that that little turbo helped wipe-up a few cars to include a WRX, audiTT, turbocharged IS300, and of course, the internets favorite, an S2000.

Dee