ISIS T25/T28 turbo: time will tell
Yeah this is the first time I've ever waited this long for a part.... Not to mention I had to ship my turbo and EWG to him... I miss those guys lol but yeah at the end of the day it comes down to how much of a rush I am in when I decide it's time to buy an exhaust.... I have some time for now so we'll see lol
So I'm curious because it seemed like this turbo had a 5 bolt downpipe flange an a lot of the kits (BEGI comes to mind) look to be 3 bolt.
Am I mistaken or are you guys using a different down pipe?
Thanks
Am I mistaken or are you guys using a different down pipe?
Thanks
Garrett turbos have 5 bolt flanges. Downpipe bolt patterns are different according to whatever turbo they are being mated to
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Took my first drive today. First impressions? pretty much what I expected.
Spool is MUCH slower than my sr20 T25. No logs yet and only a handfull of half assed full throttle pulls, but it seems like it makes max boost @ 4000-4500 RPM. That's at least 750 rpm slower than the T25. Boost does seem smoother though, not an instant snap like the t25...not sure if that means it is making smoother power, or just less power?
Stock wastegate that came with the turbo seems to be around 10psi. I will probably add a MBC soon and bring that to 14ish.
For the $ this turbo gets me back into the power range I was in before, but without the worries of rebuilding a 20 yr old core.
Like the title says... Time will tell.
EDIT: full disclosure- This swap was done at the same time as a 99 head swap. My VICS is not setup yet. I am also running a bit less timing on my start up map than my map I had on the T25.
Spool is MUCH slower than my sr20 T25. No logs yet and only a handfull of half assed full throttle pulls, but it seems like it makes max boost @ 4000-4500 RPM. That's at least 750 rpm slower than the T25. Boost does seem smoother though, not an instant snap like the t25...not sure if that means it is making smoother power, or just less power?
Stock wastegate that came with the turbo seems to be around 10psi. I will probably add a MBC soon and bring that to 14ish.
For the $ this turbo gets me back into the power range I was in before, but without the worries of rebuilding a 20 yr old core.
Like the title says... Time will tell.
EDIT: full disclosure- This swap was done at the same time as a 99 head swap. My VICS is not setup yet. I am also running a bit less timing on my start up map than my map I had on the T25.
Spool is MUCH slower than my sr20 T25. No logs yet and only a handfull of half assed full throttle pulls, but it seems like it makes max boost @ 4000-4500 RPM. That's at least 750 rpm slower than the T25. Boost does seem smoother though, not an instant snap like the t25...not sure if that means it is making smoother power, or just less power?
Lol, smoother power. What you're describing seems to be exactly what you said, slower spool. You even said, it spools slower, and less snappy, but then say it's "smoother though".

I swapped from a wrx td04 to one of these recently. (10 psi on the t25/t28 feels about the same as 14psi on the td04-13t other than 500 rpm later spool.)
The t25/t28 wastegate actuates at 10 psi which makes traction difficult in the wet. I will probably get a daily friendly 6 psi wastegate actuator.
(Photo showing techsalvager inspired hose.
)
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I might try and do a 10PSI log tomorrow coming home from autox if I remember. I think you could sqeeze 250 out of this turbo. It is slightly bigger than my old T25 and I made 225 @ 12PSI on a 96 head.
Any updates from the guys running this thing?
Trying to decide what turbo to run down the road still. Will probably try to find a used oem 2560 from a s15 though.
Trying to decide what turbo to run down the road still. Will probably try to find a used oem 2560 from a s15 though.
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I haven't gotten to drive the car much yet. My wideband was giving me **** so I am in the middle of replacing it...Then I need to retune.
I did do one autox on Memorial day and it was great. I had NO issues falling off boost even with the shitty spool of this turbo. I am still at the wastegate pressure of 10 PSI.
More to come next week I hope
I did do one autox on Memorial day and it was great. I had NO issues falling off boost even with the shitty spool of this turbo. I am still at the wastegate pressure of 10 PSI.
More to come next week I hope





I hope to see it again in the next week or 2 though! Wont have it on till winter most likely ...