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Old 11-16-2010, 09:05 AM   #21
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Quote:
Originally Posted by shuiend View Post
FWIW I am only speaking for myself in this response.
My Chinese 2870 cost me $300 shipped to my door. A new GT2871 is $1291 + shipping from ATP... If I buy they turbo with the V-Band housing it is $1391 up front.
Don't buy it from ATP.
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Old 11-19-2010, 12:13 PM   #22
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Originally Posted by TurboTim View Post
Don't buy it from ATP.
Well I know that. I was just grabbing what normal retail for it is.
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Old 11-19-2010, 12:41 PM   #23
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Originally Posted by Savington View Post

I can understand the demand for cheap turbos for folks who are stealing the handicap rail out of a McDonalds bathroom and using it for their EWG dump tube.
ROFL! Where do you get your material??? Is there some fail thread on this? HAHAHA!

Off topic - How did the ricelands perform on the track; knowing what you know?
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Old 12-13-2010, 12:56 PM   #24
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The ebay turbo's def got better. However in this aspect is a real good reason why one goes ebay over real... situation.... I had an 89 starion (one of many starquests i had) i wanted to get quick useful power in my setup i had, everyone knows of the power band range and quick spool of the evo3 ported big 16g, (maybe not here idk?) but its power range was the same as a starquests 12a converted to 18g and comes on faster and harder. Well a lot has to be done to make the swapover from the 12a based stocker to the evo3 to work on a starquest. using the ebay one i got for 200 bucks new. Had a thinner amount of metal at the turbo to manifold mounting area for me to get nuts onto the studs as to where if i had used the real deal i would have had to shave the crap out of the real deal evo3 and then have to worry about the nuts comming loose due to an untrue surface from grinding it down OR spend dough on a machine shop to rig up a way for them to be able to machine it down. NOT budget effective for anyone in making a fast daily, not track car that HAS to perform or try breaking some records or whatever. Needless to say that little bit right there made me able to be the first at the time that anyone knew of to do the swap and experience the big difference over an 18g which i had tried as well. It lasted me 2 years and the guy i sold it to 1-2 years where he finally bought another. But a new real deal turbo can die in a year for cryin out loud lol.
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Old 12-13-2010, 02:13 PM   #25
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The performance loss is fairly significant, IMO. Railz is the first person to break 300whp using a "2870", and he only ended up making 270tq at 20psi. There are two or three others with Churbos creating 20+psi in the intake manifold, and none of them are doing 300whp. I make 295tq at 17psi with a genuine Garrett - at 20psi I would likely make 315-320tq. Who else here would spend $600 today to pick up 40ft.lbs of midrange torque on their setup - guaranteed? If I offered a group buy to turbo customers, offering 40tq in the midrange for that kind of money, I'd be a very rich man.
This pretty much sums up the china turbo. I will get a real turbo next time. My reasoning is merely the fact that I spent so much on a built motor so I could support 300+ whp. With only 280whp, I could have just kept a stock motor at 250 with a lot of coin in my pocket.

I could just get a bigger china turbo, but then the increased spool time will suck the fun out of it.
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Old 12-13-2010, 02:32 PM   #26
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Quote:
Originally Posted by JasonC SBB View Post
Because it doesn't say "Garrett" anywhere in the ad, it must be a Chinacharger .. ?
The answer is in the images:



This is a "TURBOCHARGER" brand turbocharger.
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Old 12-13-2010, 06:16 PM   #27
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LOLz!
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Old 12-13-2010, 06:20 PM   #28
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lol, the ol bootleg wannabe master power tag that isnt a real tag and is a lookalike tag haha
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Old 12-13-2010, 06:42 PM   #29
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Quote:
Originally Posted by djp0623 View Post
This pretty much sums up the china turbo. I will get a real turbo next time. My reasoning is merely the fact that I spent so much on a built motor so I could support 300+ whp. With only 280whp, I could have just kept a stock motor at 250 with a lot of coin in my pocket.

I could just get a bigger china turbo, but then the increased spool time will suck the fun out of it.
Do you know for a fact that you'd make 300+ on the same pressure level and tune with an authentic unit?

NO.

Lets not get carried away too far guys.

When someone does a back to back dyno pull with everything staying same except swapping turbo from chinacharger to authentic and makes xx amount of power more on the real deal I'll be convinced.

Til then we're just poking a turd and wondering who **** it.
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Old 12-13-2010, 06:46 PM   #30
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Quote:
Originally Posted by JasonC SBB View Post
LOLz!
I'm actually serious. That one thing alone makes me suspect that probably 75% of all the world's Churbos are being produced in one single factory. Have a look around eBay as well as the various websites which sell cheap turbos, and the majority of them all seem to share that one design feature in common. A raised section on the compressor where, instead of a riveted metal tag, there is a flat machined surface onto which has been engraved the word "TURBOCHARGER" followed by some random model number GT25, GT30, etc)

Here are some examples, all taken from different eBay ads over the course of a minute or two:








That last one, in particular, kills me. Why on earth would a complete assembly number (3076) be etched onto a compressor housing, unless the person doing it didn't have the slightest clue what the number actually meant?
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Old 12-13-2010, 07:05 PM   #31
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Quote:
Originally Posted by tsiconquest88 View Post
the ol bootleg wannabe master power tag
Actual Master Power turbos have the name cast into the compressor housing, and some also have it cast in the turbine housing. Master Power turbos are made in Brazil. My dad has one of those that has been running happily for a few tens of thousands of miles on his turbo SC300. It's just a street car so he went with "cheap and disposable." Well, they are not as cheap as the chinachargers, but not nearly as pricey as Garrett et al.
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Old 12-15-2010, 02:03 AM   #32
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Quote:
Originally Posted by 18psi View Post
When someone does a back to back dyno pull with everything staying same except swapping turbo from chinacharger to authentic and makes xx amount of power more on the real deal I'll be convinced.
This argument gets used a lot and it never gets any less stupid.

Quote:
Originally Posted by Railz
set-up:
supertech 8.8:1 pistons
949 racing/m-tuned rods
lightweight crank(additional oil ports added for rod bearings. weight reduction from the other end of counter weights, NOT knife-edged)
rotating assembly fully balanced
cometic HG
stock head valve train
ported rebello head
china 2871
DW 1000cc
e85 fuel
ARTech mani,DP,full 3" exhaust
MBC
tial WG & bov
COPS
F1 racing 1.6 stage clutch 6-puck(wtf, seriously?)
STOCK 1.6 tranny ( yeah i know right?)
STOCK intake manifold
MSII
Quote:
Originally Posted by Savington
Full setup:
1862cc 8.6:1 shortblock
stock VVT head, stock cams
Supertech 83.5mm 8.6:1 pistons
M-Tuned rods
BE billet OPGs
ARP head studs, OEM head gasket
ABSURDflow v-band manifold/downpipe
Garrett GT2871R - 52 trim compressor, .86 A/R TiAL turbine housing
TiAL MVS EWG
3" open exhaust
Blox B18 intake manifold
stock B18 throttle body
Precision 600hp intercooler
AEM EMS, self-tuned
ID1000cc injectors
ABSURDflow SS fuel rail
Fuelabs FPR, 70psi base pressure
Walbro 255HP
E85
6-speed/3.909 Torsen
Compare torque curves:

Name:  railzvssavington.jpg
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Size:  26.2 KB

Our setups have small differences - he has a 1.6 with a ported head, I have a stock VVT head, but we have basically the same manifold and same fuel - and yet I make SIGNIFICANTLY more low-end and mid-range torque than he does.

Anyone else still not convinced?
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Old 12-15-2010, 02:20 AM   #33
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Your 1.8 with vvt makes more midrange torque than his 1.6? NO WAY!! Who gives a **** about your manifold and fueling? You have more displacement on him. You guys also have different turbos (despite them having the same name). If the specs on the turbos are different, which they are, (inducer/exducer/etc/blahblahblah) that also contributes to the power difference.
You getting pissy about people not taking your word as gospel isn't helping you. I respect your opinion though.


*edit: just looked over your guys' setups too and they're not similar at all IMHO.

Last edited by 18psi; 12-15-2010 at 02:31 AM.
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Old 12-15-2010, 02:26 AM   #34
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Yours is ball bearing his is journal.

Your turbo's specs (from a quick google search)
Quote:
Turbine
-Wheel: 53.85mm w/ 76 trim
-Housing: .86 or .64 ar
-Maps

Compressor
-Wheel: 71mm w/ 56 trim
-Housing: .60 ar

His turbo specs (from a quick ebay search)
Quote:
TURBO SPEC:

gt28 turbo charger

Intake :3 inch
Outlet: 2 inch
Compressor trim: .60 ar
Compressor Wheel diameter: 54.28 /71.32
Turbine wheel diameter : 45.47 / 52.90
Exhaust trim: .84ar
Turbine flange type: t25 flange
Downpipe flange type : 240sx 5 bolt type
Cooling type: oil cool only
Horsepower rating: 350-400hp
BOLT ON TURBO FOR S13 S14 S15 (SR20 MOTOR)

(wet float bearing)

They are clearly not the same. So why should they perform the same? Just cause the chinese decided to copy over the 2871 name?

And who even knows if posted specs for his turbo are actually correct?

I measured my 3076 when it came in and it was different than what was posted.
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Old 12-15-2010, 02:41 AM   #35
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Quote:
Originally Posted by levnubhin View Post
I think it's also worth mentioning that that turbo I used is still alive with about 10k on it. In fact we just put about 2000 miles on it and beat the hell out of it at the gap.
Do you think it would last a track day? I wish it would but I doubt it.
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Old 12-15-2010, 02:50 AM   #36
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For under 300 bux you can find out
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Old 12-15-2010, 03:24 AM   #37
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Quote:
Originally Posted by 18psi View Post
Yours is ball bearing his is journal.
...seriously? Are you trolling? Bearing type doesn't affect the shape of the curve, and on 28/30 frame turbos it's not even that much of a benefit.

Quote:
And who even knows if posted specs for his turbo are actually correct?

I measured my 3076 when it came in and it was different than what was posted.
Let's address this first, djp0623 measured his 2870 when it came in:
https://www.miataturbo.net/showthrea...highlight=2870

Quote:
Compressor
Ind53.1mm
Exd 69.7mm
exhaust
Ind 51.7mm
Exd 45.7mm
Now let's look at mine:
Quote:
Compressor
Ind51.2mm
Exd 71.0mm
exhaust
Ind 53.8mm
Exd 47.0mm
Within 1mm on the compressor side - I hope we can agree that's essentially the same. We have lots of discussion about the Disco Potato vs the 2871 and that's an 11mm difference.

My turbo is 2mm larger on the compressor side, so we should see a slight bias towards high-end in my chart, and Railz's turbo should make a little more low end.

But that's not what we see at all.

Quote:
You getting pissy about people not taking your word as gospel isn't helping you. I respect your opinion though.
I'm getting pissy because you're ignoring good data. There are at least 3 recent examples (levnubhin, railz, djp0623) of Chinese turbos making crap low/midrange and less-than-normal high-end torque when compared to similar setups with Garrett units, but you seem to think that proves absolutely nothing, and we should obviously wait for an expensive back-to-back test to occur so we can REALLY see, since there's no other test that will tell us anything at all about the performance of these turbos.

Railz's setup is the most similar to mine - he's running E85 and an ARtech shortram manifold, two of the biggest contributors to low-end torque you can make. Yes, I've got more displacement, VVT, and an intake manifold, but he's got the ported head, a worked crank and 3psi more boost. If he had a similar curve to mine, except for being a little down on torque, I wouldn't be making a stink - the shape of the curve is what sets off the alarms for me. Do you really think that the VVT head and displacement is worth 100ft.lbs at 4000rpm?

Want to see what displacement and a slightly smaller turbo SHOULD look like? This is BBundy (2.0 FM stroker, 3071R .64, built 99 head, grafted 94 IM, ramhorn manifold) vs me (1.9, 2871 .86, stock VVT head, grafted B18 IM, AF shortram, E85):

Name:  bbundyvssavE85.jpg
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Same lines, just adjusted up/down. This is the kind of differences that head flow, displacement. etc. should make - you can even see the Honda IM outflowing the stock 94 manifold up top by a tiny bit.

By the way, I feel like I should apologize to lev, railz, and djp. I rag on their setups a lot when I argue about garrett vs. China, but it doesn't reflect at all on their setups. They've all got top-notch parts and I'm sure their tunes are awesome - I have little doubt that they'd each see much better numbers with just a turbo swap and a retune.
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Old 12-15-2010, 03:34 AM   #38
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So if bearings make little difference, wheel specs being different "aren't significant" from what you're saying, The only thing left is the design of the compressor/turbine housings which appear to look the same too.

So what is causing the difference in power since everything else in your opinion is "almost the same"?

Wheel DESIGN? Looks similar but I haven't inspected both closely to double check


I'm not mad or choosing to ignore your data by any means.
As I said I respect your opinion and am happy with my turbo, so I'm not fanboyishly taking sides, just more of a "devils advocate" type of deal. authentic is clearly better, I just want to know what makes them put out better lowend/midrange.

Last edited by 18psi; 12-15-2010 at 03:35 AM. Reason: .
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Old 12-15-2010, 03:45 AM   #39
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Quote:
Originally Posted by 18psi View Post
So what is causing the difference in power since everything else in your opinion is "almost the same"?

Wheel DESIGN? Looks similar but I haven't inspected both closely to double check
That's certainly where I'd put my money, especially since the majority of the power loss is seen at lower RPMs (and thus lower flow rates). The reliability and manufacturing is easy to figure out in comparison to the aerodynamic capabilities of the wheels.

Just look at what Garrett has done with the GTX setups - a compressor housing and wheel design change picks up 10% in flow.
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Old 12-15-2010, 05:02 AM   #40
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I think precision turbos are a great option and cost significantly less than a ball-bearing unit.
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