is this between a 2554 and 2560
#1
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is this turbo between a 2554 and a 2560?
http://www.ebay.com/itm/New-Design-T...item3f0441846f
Please help I cant tell by the spec I am a total newb. Please help
http://www.ebay.com/itm/New-Design-T...item3f0441846f
Please help I cant tell by the spec I am a total newb. Please help
#2
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It is around the same size as the 2560. The wheel sizes are the same but the housings are different. The compressor housing is smaller (has a smaller A/R) which I can't see having too much effect (please someone educate/correct me). The turbine housing has a larger A/R than a 2560 which will have the effect of shifting spool to a later RPM and letting the turbo breathe a little better up top.
So you can continue de-noobing: http://turbobygarrett.com/turbobygarrett/turbochargers
You will find turbo specifications here. Also, if you click the Turbo Tech link at the top of the page, you will find Garrett's excellent turbos for dummies guide. I've read it a few times.
So you can continue de-noobing: http://turbobygarrett.com/turbobygarrett/turbochargers
You will find turbo specifications here. Also, if you click the Turbo Tech link at the top of the page, you will find Garrett's excellent turbos for dummies guide. I've read it a few times.
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addition -- when you are trying to determine turbo size for a target wheel horsepower, you need to add to the flywheel number the estimated driveline loss
do driveline losses change with the addition of horsepower, or do they remain constant?
I say more constant than as a percent
just my opinion, worth what you are paying for it
do driveline losses change with the addition of horsepower, or do they remain constant?
I say more constant than as a percent
just my opinion, worth what you are paying for it
#6
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do driveline losses change with the addition of horsepower, or do they remain constant?
I say more constant than as a percent
I say more constant than as a percent
http://www.modified.com/tech/modp-10...s/viewall.html
Yeah, no definitive answer. The 15% rule of thumb I was taught may be completely full of crap, may not be.
#7
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Ah, that would be one way of looking at it. Or in the above case, you subtract 15% to see if the number is what you want whp from the turbo. (100 crank hp minus 15 percent would mean 85whp, as an example)
You ding dang done made me google. And it's an absolutely fascinating subject that has an infinite amount of answers.
http://www.modified.com/tech/modp-10...s/viewall.html
Yeah, no definitive answer. The 15% rule of thumb I was taught may be completely full of crap, may not be.
You ding dang done made me google. And it's an absolutely fascinating subject that has an infinite amount of answers.
http://www.modified.com/tech/modp-10...s/viewall.html
Yeah, no definitive answer. The 15% rule of thumb I was taught may be completely full of crap, may not be.
the purpose of my caution was to make adjustment to the calculations if using the Garrett site to select a turbo based on a target wheel HP [because the Garrett site example calculations only use flywheel HP] without the adjustment for driveline loss you will come up short
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on the miata the drivetrain loss is around 25-30rwhp.
anyways, that turob has the same size compressor wheel as my 60mm 50 trim T3 wheel. It outputs like a 2554 with the max being around 30-35 lb/min. IT's running out of steam of my 1.6L around 240rwhp...which is fine because I never plan on going past that.
The turbine seems to be the same size as the T25 series...
so the turbo is techincally larger, and correctly labeld a T28, but since the compressor wheel itself is one of the smaller 60mm trims, it's not going to output as much topend as the 2560 would.
So to sum up, yes it's between a 2554 and 2560.
anyways, that turob has the same size compressor wheel as my 60mm 50 trim T3 wheel. It outputs like a 2554 with the max being around 30-35 lb/min. IT's running out of steam of my 1.6L around 240rwhp...which is fine because I never plan on going past that.
The turbine seems to be the same size as the T25 series...
so the turbo is techincally larger, and correctly labeld a T28, but since the compressor wheel itself is one of the smaller 60mm trims, it's not going to output as much topend as the 2560 would.
So to sum up, yes it's between a 2554 and 2560.
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Ok cool but the AR on your is like .63 according to garrett the turbine ar determines how fast it spools and I want as much boost down low as possible. how much difference you figure the .86 ar and smaller turbine is going to make on fast spooling? 500rpm? 1000Rpm.
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Ok this might sound crazy but could I swap over the turbine housing from the 2554. So us the compresor and chra from this china turbo and the turbine from the 2554.
The turbine is 53mm in both and looking at them from the out side which is prob no indication for what is on the inside it looks identical.
I am sure this is a stupid idea I just thought I would ask. If my some chance it would work is it a good idea. The 2554 is letting a lot of oil thru and I would like to change it but cant afford the 2560/800$+ turbo for a little while. the cost of diypnp has tapped me out.
The turbine is 53mm in both and looking at them from the out side which is prob no indication for what is on the inside it looks identical.
I am sure this is a stupid idea I just thought I would ask. If my some chance it would work is it a good idea. The 2554 is letting a lot of oil thru and I would like to change it but cant afford the 2560/800$+ turbo for a little while. the cost of diypnp has tapped me out.
#18
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on the miata the drivetrain loss is around 25-30rwhp.
anyways, that turob has the same size compressor wheel as my 60mm 50 trim T3 wheel. It outputs like a 2554 with the max being around 30-35 lb/min. IT's running out of steam of my 1.6L around 240rwhp...which is fine because I never plan on going past that.
The turbine seems to be the same size as the T25 series...
so the turbo is techincally larger, and correctly labeld a T28, but since the compressor wheel itself is one of the smaller 60mm trims, it's not going to output as much topend as the 2560 would.
So to sum up, yes it's between a 2554 and 2560.
anyways, that turob has the same size compressor wheel as my 60mm 50 trim T3 wheel. It outputs like a 2554 with the max being around 30-35 lb/min. IT's running out of steam of my 1.6L around 240rwhp...which is fine because I never plan on going past that.
The turbine seems to be the same size as the T25 series...
so the turbo is techincally larger, and correctly labeld a T28, but since the compressor wheel itself is one of the smaller 60mm trims, it's not going to output as much topend as the 2560 would.
So to sum up, yes it's between a 2554 and 2560.
/Bump from the past, yo!
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should be. it's only a 30 lb/min wheel. I run 13-15psi on my 1.6L and seeing about 240rwhp...so you'll be at the upper limits...possible more tq than you'd want to push...maybe keep it to 12psi until you can dyno.