View Poll Results: Which turbo for my 1.8 swap?
GT2860RS (Disco Potato)
13
54.17%
t3 Super 60
11
45.83%
Voters: 24. You may not vote on this poll
Disco Potato or T3 Super 60?
#41
Mark, Tim
I am new to turbos, but my research is telling me you guys have those turbine inducer/exducer labels backwards.
smaller
Consequently, I did run the numbers and your calcs appear correct, only the labels are backwards.
As a side note...
Why in the heck does Garrett make everyone jump through hoops to figure out their turbine specs? It took me forever to confirm that Garrett's turbine "wheel diameter" is actually the turbine inducer just so I could do the algebra.
The only clue Garrett provides on their website is this snippet from the GT Basics / Nomenclature page (sixth paragraph):
"...units which utilize a 53mm turbine wheel (as measured at the inducer) are now referred to as "GT25" frame size..."
http://www.turbobygarrett.com/turbob...gt_basics.html
If you look at Garrett's specs for any GT25XX turbo, indeed the provided "wheel diameter" is 53mm.
I am new to turbos, but my research is telling me you guys have those turbine inducer/exducer labels backwards.
smaller
Consequently, I did run the numbers and your calcs appear correct, only the labels are backwards.
As a side note...
Why in the heck does Garrett make everyone jump through hoops to figure out their turbine specs? It took me forever to confirm that Garrett's turbine "wheel diameter" is actually the turbine inducer just so I could do the algebra.
The only clue Garrett provides on their website is this snippet from the GT Basics / Nomenclature page (sixth paragraph):
"...units which utilize a 53mm turbine wheel (as measured at the inducer) are now referred to as "GT25" frame size..."
http://www.turbobygarrett.com/turbob...gt_basics.html
If you look at Garrett's specs for any GT25XX turbo, indeed the provided "wheel diameter" is 53mm.
#44
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how often do you expect to rebuilt a GT-R turbo? I'm pretty sure they last a very long time assuming proper maintainence/tune/etc.
If something goes thru the turbine, that's another story.
#46
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I'm also considering a T3/TO4E 50 trim as an option now. I like that I could run it external wastegate where I would have to weld the flapper shut on a GT2871R or potato to do that and then I would be paying for something I'm not using. Also knowing that I can rebuild it cheaply is a plus. So now I'm down to a GT2860RS, GT2871R, or T3/TO4E 50. Now just to find one cheap enough to make me pull the trigger. I have at least a couple of months to find one, so used (read cheap) is better.
#47
Boost Czar
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well if you wanna go new, this price looks reasonable:
http://www.rogueusa.com/Garrett-T3-T...t-t3to4e50.htm
http://www.rogueusa.com/Garrett-T3-T...t-t3to4e50.htm
#48
I'm also considering a T3/TO4E 50 trim as an option now. I like that I could run it external wastegate where I would have to weld the flapper shut on a GT2871R or potato to do that and then I would be paying for something I'm not using. Also knowing that I can rebuild it cheaply is a plus. So now I'm down to a GT2860RS, GT2871R, or T3/TO4E 50. Now just to find one cheap enough to make me pull the trigger. I have at least a couple of months to find one, so used (read cheap) is better.
Mark
#49
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well if you wanna go new, this price looks reasonable:
http://www.rogueusa.com/Garrett-T3-T...t-t3to4e50.htm
http://www.rogueusa.com/Garrett-T3-T...t-t3to4e50.htm
#51
Just so you all know those ebay turbos have and do work most of the time if used right. On our import engines where the oil pressure is most of the time double what american engines are the turbos tend to blow the seals out. If you put an oil restrictor inline of the oil feed line you will have much better luck.
#55
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I am considering it but like was said earlier in this thread, I'd loose a couple hundred as soon as I start the car. If I do do it, I'd probably sell the turbo with the manifold and downpipe too.
I'd much rather someone just buy the turbo though.
I'd much rather someone just buy the turbo though.
#59
The 2876's TO4S compressor wheel is not a GT wheel, it was introduced in 1976, and is outdated compared to the modern GT wheels. The older design wheel has more blades, that are thicker and angled differently, making it heavier and less efficient. At 76mm on the exducer it is significantly larger, further adding intertia to the rotating mass.
Besides the compressor being older technology and over sized (50 lb/min, or roughly 500 crank hp), it is mated to the same tiny T25 turbine wheel from the 28RS; creating a size and shaft speed mismatch. The NS111 turbine wheel flows only 17-21 lb/min depending on housing option, and cannot generate the shaft torque required to efficiently spin up the large T4 compressor. Both turbine to compressor wheel size ratio, and shaft speeds must be well balanced for the turbo to operate efficiently.
The result of the mismatch is higher exhaust gas speeds to spin up the compressor (higher engine speed, more lag), and more exhaust restriction from the undersized turbine once it does spin up (higher backpressure and thermal load/EGT, ie more detonation prone, and limited power level). In other words, the potential flow capacity of the compressor is never realized, and the same power is produced that could be done with a smaller turbo, albeit with more lag.
Garrett has since phased out the 2876 as a performance turbo in favor of the newer 2860, 2871 and 3071, which all have increased turbine to compressor wheel ratios and better matching shaft speeds.
This information is stated in the catalog on the Garrett website:
"Best suited for unique applications such as asymmetric turbo installations"
"Not recommended for general performance applications"
http://www.turbobygarrett.com/turbob...R_705330_2.htm
This isn't to say that the 2876 doesn't work; it has been proven to make 400whp, just that it can be done more efficiently and with better spool.
#60
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I was generalizing. It's the same turbine with a slightly larger compressor, it flows 50 lb/min vs 45 lb/min, otherwise the islands are very similar themselves, minus the RPM rates. You should expect better spoolup and possibly better hp-per-psi results with the 2871.
the purpose of me posting his dynos was simply to show what ballpark you'll be in.
the purpose of me posting his dynos was simply to show what ballpark you'll be in.