Which turbo to use? sr20 T25 or greddy TD04H?
 

Greetings all.

I've had my miata for about a year now and have been collecting items I'll need for boost. I have 2 turbos to choose from:

SR20det T25 turbo and a Greddy TD04H

My goals are around 200 hp which I know both are more than capable of producing. I would like something responsive...not laggy and both seem to work well since they are small and don't require much spool.

The T25 is oil and water cooled...while the TD04 is oil cooled only.

Both turbos are in great condition as far as I can tell.

My car currently has 242K miles on it with surprisingly good compression 180-185-180-185. I have a spare motor at home as well in case the motor goes to shi* and a spare car.

I live in CA and eventually have to smog the car...so I am leaning more towards the Greddy due to it having a CARB (I do have a MS1 I will be tinkering with)

So turbo gurus, is the T25 far superior than the TD04 in terms of performance and longevity?

Advice is much appreciated.

Short answer, no.

Longer answer, your decision should be based on your downpipe/manifold/condition of the turbo itself. The turbos have a very similar performance aspect.

I've had both, although my current t25 is freshly rebuilt. I definitely enjoy the t25 more, for power and response. I feel just that much more confident that it's water cooled too. Both for my engine oil and sanity.

The TD04 that I just bought is oil and water cooled? Subie TD04.

I believe the TD04 has quite a few variations, and the TD04H common to the Miata via the Greddy kit is only oil cooled. At least mine is, I assumed they were all like that.

Yes the TD04 has about 1000000 configurations.

Did you have similar set-ups? Same type of manifold/dp and tuning to compare them equally?

I definitely agree with you about the water cooling benefit of the T25

need to know more about the td04.

is this for a 1.6L miata? what are you driving styles?

1.6

Driving style: spirited and/or somewhat aggressive.

This is my daily driver so I commute with it so I'm looking for reliability, predictability (gradual/linear power vs slow/laggy spool). Maximum power is not my goal.

Td04h is the one from the greddy kit. I have 2: one with a supposed 1500 miles and a spare with unknown mileage.

FYI from what I have heard from others with TD04/T25s is the opposite of what you think. A big turbo is predictable and gradual as it spools up, whereas a T25 is a lightswitch.

I get what you are saying though.

...Nah...

Dann