I've been making some small changes to my setup: specifically a smaller intercooler and now a smaller turbo. My goal is gaining a crap ton extra low-end torque without a major trade off up top. I still have a 220-230rwhp goal.

I wanted to simply swap on a 50 trim compressor wheel on my T3 in place of my S60 wheel, I figured that would do the ticket. I ended up with an eBay turbo after weighing a few pros and cons.

So far I'm pleasantly surprised with it. I was really afraid how the different the turbine would be since the specs they gave me were slightly different than a standard turbine from Garrett. As far as I can determine, the wheels are the same but for extended tips on the inducer. And from what I can assume, that would only be a good thing. The spacing/size/shape/profile of the exducer fins are identical.

Same with the compressor wheel. It was spec'd as a 50 trim, but the measurements of the inducer were just off. The lengths of the fins are the same but the design is a little different. It's hard to explain, but the inner small fin is a different angle and spacing.

I'm not sure how this turbo will react in the real world, but I'm thinking it will spool faster like I want and still support my power goal.


now for the pics:

Out of the Box:







Had the wastegate ported at BEGi:






comparing the turbines:











Comparing the compressor wheels:















Ready to install:

 

Cool...ready to hear how it turns out.

 

I have coilovers to install on Saturday, if I have time I'll do it then.

 

Oh no you didn't!

What is the world coming to!

So braineack doesn't have a Garrett turbo. BLASPHEMY!

 

That oil drain is a genuine Garrett part! I'm also installing a smaller tubo...is that even legal?

 

lol!

 

Let us know which turbo you bought exactly! I'm thinking of ditching my gt2259 plans

 

I bought this one:

T3 TURBO CHARGER INTERNAL 8PSI WASTEGATE .48AR TURBINE:eBay Motors (item 160344420666 end time Jul-24-09 18:06:18 PDT)

Seller did something a little shady. I sent an offer of $155 but we agreed at $175. He sent a Paypal Payment Request to avoid eBay fees. I took a risk and went for it, luckily he pulled through. I talked to him on the phone and took a chance on love.

Seller: jp_drift_showoff

T3 TURBO CHARGER INTERNAL 8PSI WASTEGATE .48AR TURBINE

I made sure the auction had the compressor and turbine specs, otherwise I would have never considered it.

 

I like your style. You build something with a set torque goal and you're happy with it.
My goal was originally to have 1 RWHP per 10 lbs. Since my car weighs 2350, this means I need 235 rwhp. This can be done with my SR20 T25, and then I'm done. I have too many projects to wrench on instead of constantly messing with the Miata. You have to draw the line somewhere...Or do you?

 

I figure if I only have a 220-230rwhp goal, I've been more than happy with the power for years now. Why have a turbo that's good for 300-320rwhp. I'll benefit from faster spool and more peak torque...with the same peak HP...why not?

 

Brain, are you selling your T3S60?

 

probably not.

 

I wish I was satisfied with reasonable power goals :( :(

 

right, it would be so nice if I were happy with what I have.
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I was thinking about a redux of my setup, but SO said no building motors in the garage this year.

Topic came about due to a $400 LS1 on CL in need of a rebuild. She not only said I didn't have time for that project, but that I couldn't build a 1.8L either. She's right...but I still told her that her ***** felt just like her sister's last night.


$175 is hella cheap for a turbo. I'm still trying to wrap my mind around all this. Some of ya'lls setups will get to the point where a replacement turbo is less than 10% the total cost of your setup, whereas replacing mine would be over 30% of what I've got into.

This could make it pretty easy to swap trims and find what you really like, which I guess is basically what Scott did.


I'd love to have more power, but without a built motor the 220-230whp limit with best spool characteristics just makes sense.

 

Thanks for the info Brainy,

does the turbo seem solid out of the box? Any cleaning/etc that I'd need to do before tossing it on?

 

Out of the box, yeah. I had it shipped directly to BEGi so they could port it, so I cant say if they cleaned it a bit. But I didn't clean anything before I snapped those shots and everything was shavings free. There was a thin coat of oil/grease on the flanges which was a nice touch. As far as I can tell it's going to be a good unit.

 

This is so exciting. If reports of reliability/quality keep rolling in from experienced/knowledgeable folks like yourself that tested them, then prices/cost for turbos will plummet. More people will be able to afford to turbo their miata's. Many will be able to afford to upgrade to bigger/better units. Oh boy I'm getting all giddy just thinking about it

 

I just wish I knew how that turbine was really going to react. As far as my feeble brain can determine it should be positive.

The exducer bore and shape/spacing is all identical. This is where the backpressure comes into play, speeding up the wheel and where it can choke out up top. People will actually "clip" the trailing edges off to promote flow through the turbine at the expensive of spool.

Typically when you go to a Stage II or Stage III wheel not only does the inducer/exducer's diameter increase proportionately, but the spacing between fins increases. This reducing the backpressure as the exhaust gasses can more easily flow through at high rpms, again at the cost of spool.

Since I have extended leading edges I can see where it wouldn't really matter for spool, the exducer still produces the same restriction and flow. But I can maybe see it being better for top-end as there's more surface to push against when there flow increases.

I could be wrong, but that's what I'm thinking. It's already a larger turbine than all you GT25 and GT28 folks and I'm on a stock 1.6L motor.


But the compressor wheel has a 6mm smaller inducer, which will move my efficiency curve and should spin faster. So if the turbine remains a constant I should end up with the turbo I actually wanted.

I could have simply slapped the compressor wheel on my current turbo, as you can see i have one, but I decided to get a brand new unit a try. My turbo is was used when I got it 5 years ago, it's composed of many different turbos's parts, been rebuilt a few times, the turbine wheel isn't perfectly true, and I think it may be the root of some oil burning I'm still dealing with. So I figured, why not.

 

Is it in yet?
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