so I got my hands on a used, rebuilt T25 for a reasonable price. It has an internal wastegate, but no actuator. Do I need one for the 3b? If so, what's a good option?
T25 on 3B
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- #2
It looks to be in good nick to me, no visible wear or play on any components as far as I can tell, what ought I be looking for?
That's a T28. It's one size up from the T25 and unfortunately will be in surge for most of your driving range.
T25 has 0.48 A/R compressor cover with a ~40mm intake. That one is ~46.5mm intake. The compressor A/R isn't important, I'm just using it for an identifier here. I have the same turbo at home and it was a terrible match on my 3.9L Isuzu 4BD1T.
T25 has 0.48 A/R compressor cover with a ~40mm intake. That one is ~46.5mm intake. The compressor A/R isn't important, I'm just using it for an identifier here. I have the same turbo at home and it was a terrible match on my 3.9L Isuzu 4BD1T.
GTSSportCoupe
2LTE abuser
Fortunately you could probably find someone looking to upgrade from a T25 to a T28 and make a trade. A local club member has a T25 on his 3B and it is matched really well. Looks tiny on his motor, but works great.
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- #5
Well fxxx
It was advertised as a T25.
It was advertised as a T25.
On the bright side, you can probably re-sell it for more than you paid.....
Here's a T25: Garrett t25/28
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- #7
Well I hope I can at least get my money back on the T28...
So now I have a T25.
So now I have a T25.
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- #8
I think that first turbo might have been just a T25 with a .60 AR compressor, it's super hard to find info on this stuff. Anyway I bought the other one linked so hopefully that arrives this week.... and have got a flange coming from Autobend to get started on a manifold.
I've got all the info on T25 vs T28 etc. That's 100% a T28 in your above photo and the good part is you can sell it for more than a T25. If you put a T25 compressor wheel in there you'd see a big gap right around.
The sizing split is based on turbine inducer (OD) size. Under 53mm and it's T25, over 53mm and it's T28. The 60mm OD compressors are matched to the turbines with T28's.
There was a T25G turbo with a larger A/R compressor, but that's not what you've got there. The T25G is a high flow but poor surge resistance.
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- #10
Right, cheers. It's for sale anyway if you know of anyone looking for one...
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- #11
Ok so I flipped the T28 and got my money back, and my T25 arrived. Looks in good nick but has some slight damage to the compressor blades. .48 A/R on compressor and .49 cast into the turbine inlet. Also got my 3b exhaust manifold flange to build a manifold, need to get a t25 flange before I can do that. Also got a used oil pan and a downward facing oil filter mount.
Need to:
-get compression test to make sure I'm not wasting my time
-build manifold
-get oil lines for turbo
-get bung welded into spare oil pan for oil return
-get air intake piping
-get a downpipe
-get a pyro and boost gauge
-something to hook the wastegate up to the compressor, just a bit of pressure rated hose?
-get exhaust manifold gasket
-turbo gaskets?
-gasket for oil filter mount
-delete clutch booster and fit non-boosted master cylinder
-move p/steering reservoir to sidewall of engine bay
-check/adjust valve clearances
I think that's all
What am I going to see with stock fuelling and whatever mild boost Te T25 supplies?
Need to:
-get compression test to make sure I'm not wasting my time
-build manifold
-get oil lines for turbo
-get bung welded into spare oil pan for oil return
-get air intake piping
-get a downpipe
-get a pyro and boost gauge
-something to hook the wastegate up to the compressor, just a bit of pressure rated hose?
-get exhaust manifold gasket
-turbo gaskets?
-gasket for oil filter mount
-delete clutch booster and fit non-boosted master cylinder
-move p/steering reservoir to sidewall of engine bay
-check/adjust valve clearances
I think that's all
What am I going to see with stock fuelling and whatever mild boost Te T25 supplies?
- Thread starter
- #12
Slight damage to compressor blades - is this ok? No play in anything I can feel
That's the turbo. The compressor wheel looks pretty good, I'd smooth the edges with fine sandpaper and clean all the oily crap off.
With 10psi boost you should have ~25% more torque and about 15-20% more power. I'm not aware of anyone dyno testing one of my turbo matches on these engines.
With 10psi boost you should have ~25% more torque and about 15-20% more power. I'm not aware of anyone dyno testing one of my turbo matches on these engines.
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- #14
I'm intending to get my engine dyno'd before and after turbo, don't intend to touch the fuelling for a start.
You'll gain a few percent with a turbo and no extra fuel. It'll be quieter, smoother, warm up faster and run cooler under load.
Then you turn up the fuel......
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- #16
Anyone got the Auber gauges? Looking at the 2813 2-channel gauge with this boost sensor
3 Bar, 48 PSI, Boost Sensor for Diesel Engine [AUBER-303] - $42.76 : auberins.com, Temperature control solutions for home and industry
and this EGT probe
EGT Probe, Exposed Tip [TC-KEGT] - $36.50 : auberins.com, Temperature control solutions for home and industry
gauge
Automobile Multimeter, Dual Channel [SYL-2813] - $79.95 : auberins.com, Temperature control solutions for home and industry
Slightly cheaper than buying 2 separate gauges and possible neater for packaging, if it'll fit in the 1DIN slot under the head unit, set in a blanking plate
3 Bar, 48 PSI, Boost Sensor for Diesel Engine [AUBER-303] - $42.76 : auberins.com, Temperature control solutions for home and industry
and this EGT probe
EGT Probe, Exposed Tip [TC-KEGT] - $36.50 : auberins.com, Temperature control solutions for home and industry
gauge
Automobile Multimeter, Dual Channel [SYL-2813] - $79.95 : auberins.com, Temperature control solutions for home and industry
Slightly cheaper than buying 2 separate gauges and possible neater for packaging, if it'll fit in the 1DIN slot under the head unit, set in a blanking plate
- Thread starter
- #17
also do I need to hook up the water cooling or is it not necessary? have read both ways
