ISIS T25/T28 turbo: time will tell
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Well, with spring coming soon I am piecing together everything I need to get my car back on the road. Last year I spent some serious $$ on xida's, TSE 11.75" brakes, a fully built bottom end, refreshed 99 head, and some safety bits... not to mention a ton of money into my paint job.
Long story short, I have invested a ton of money lately into the miata and need to start saving for other things (house mainly). When it came to replacing my shot turbo I turned to the budget CHURBO world.
ISIS T25/T28 turbo:



I still need to drill out the flange to accept my M10 INCO studs, and clock the turbo.
This thread is just intended to document this turbo as I go to some autox/ HPDE this summer. Anyone else have any experience with it?
Long story short, I have invested a ton of money lately into the miata and need to start saving for other things (house mainly). When it came to replacing my shot turbo I turned to the budget CHURBO world.
ISIS T25/T28 turbo:



I still need to drill out the flange to accept my M10 INCO studs, and clock the turbo.
This thread is just intended to document this turbo as I go to some autox/ HPDE this summer. Anyone else have any experience with it?
Ahh stoked to find out how this works out. I picked p the isis a few months ago but won't be able to actually find out about it until next year when I have all the parts I need lol
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Yeah I am interested. I screwed up my T25 last year when I was rebuilding it by trashing an oil ring that isnt provided in the rebuild kits. I figured I should try this rather than going through yet another 20 yr old rebuilt SR20 T25.
I wish I had the funds to do better... but I chose ISIS Churbo + FM oil cooler rather than no oil cooler and fancy turbo.
Probably wont have this up and running until May. I still have some other work to do on the car once it warms up.
I wish I had the funds to do better... but I chose ISIS Churbo + FM oil cooler rather than no oil cooler and fancy turbo.
Probably wont have this up and running until May. I still have some other work to do on the car once it warms up.
Still gonna be done way before mine haha... I'm looking at early/mid 2014. I never thought about drilling out for larger studs... Maybe I can have artech do it for me since he has the turbo right now lol
Is this the exact same as an s13 oem sr20 t25 then? Do they make a gt2560 replacement one, or does it skip straight to the big t28 in their lineup?
I was looking at this before *ISIS RS3871 Turbo - Nissan SR20DET - Enjuku Racing Parts, LLC
I thought that could be fun with e85, not for long on my stock block though haha.
I was looking at this before *ISIS RS3871 Turbo - Nissan SR20DET - Enjuku Racing Parts, LLC
I thought that could be fun with e85, not for long on my stock block though haha.
this is the supposedly the drop in turbo upgrade the sr20det guys on zilvia have been raving about. One of these just arrived at my door the other day and it looks pretty good. For the price, can't go wrong
supposed to be a gt2560 equivalent or direct replacement for a t28 off an s14/s15?
supposed to be a gt2560 equivalent or direct replacement for a t28 off an s14/s15?
this is the supposedly the drop in turbo upgrade the sr20det guys on zilvia have been raving about. One of these just arrived at my door the other day and it looks pretty good. For the price, can't go wrong
supposed to be a gt2560 equivalent or direct replacement for a t28 off an s14/s15?
supposed to be a gt2560 equivalent or direct replacement for a t28 off an s14/s15?
And just for the hell of it, here is my ISIS with a grimspeed adjustable IWG bracket so I can run EWG without welding the IWG shut lol

Upgrade being that the sr20det from s13's or the other cars that had the t25 vs the latter t28 that came on later year cars. I guess the difference could be the comparing the gt2554 vs gt2560r
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No. I can try and take some rough measurements tonight. Obviously I can only measure one diameter without taking the turbo apart.
Is it the smaller or larger side that should be 60mm?
Is it the smaller or larger side that should be 60mm?
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Obviously can't measure the big side without disassembly...
Compressor Inducer (small side) = roughly 42mm
Turbine Exducer (small side) = roughly 46mm.
I cant really get my set of calipers in there. I COULD take it to work and measure. Maybe I will re-measure when I bring it to work to drill out the flange.
Compressor Inducer (small side) = roughly 42mm
Turbine Exducer (small side) = roughly 46mm.
I cant really get my set of calipers in there. I COULD take it to work and measure. Maybe I will re-measure when I bring it to work to drill out the flange.
+1. Big turbines = big boners.
Question, being a "off-brand" turbo, do you think that it IS .86 a/r or just stamped that to make it look more like the popular turbos?
Either way I don't think I've ever read a bad thing about the ISIS turbos. Looking forward to see your experience with it.
Question, being a "off-brand" turbo, do you think that it IS .86 a/r or just stamped that to make it look more like the popular turbos?
Either way I don't think I've ever read a bad thing about the ISIS turbos. Looking forward to see your experience with it.
it's common to see a .86 A/R t25 housing.... see the SR20 T25. this thing will spool well, make tons of mid, and still be able to make ~240-250 up top at reasonable levels of boost.







