Agreed. And what's so bad about staff abuse? I'm sure all of you abuse your staffs every once in a while.

 

Sigh.


For 200whp? 2554 or 2560. The 28 series will spool much slower on both engines because of the larger turbine wheel. Stick with 25 series. Or don't and have sucky spool. It won't matter to me either way when I take my car out to the track what you did on the other side of the world.

 

Yes it will. You'll care. You'll be so mad. You'll hate. Be a hater. You'll be an oppressor of all that is good in the world. You're everything that's wrong with this forum.

just tell him to build his car. don't mention details. don't mention right and wrong. everyone gets a participation trophy.



PS: I like that OP voted "ALLOFIT". Seriously. this guy is cool in my book, even if he's using the wrong engine

 

what just happened here?

 

Someone brought a 1.6 to a 1.8 fight

 

never do that!

 

Thanks again for the proper criticism and such and thanks for trying to convince me to get a 1.8 hehe.
This car is not gonna be a track beast or anything like that. Like kiwi said above I just have casual competitive targets at this point.

Not wanting to be rude, but why would it be the wrong engine, I know the 1.8 would get a lot faster spool and a beefier torque curve.
I just want to work with what I have, which is a 1.6. Maybe once I get the boost bug I realise that I want more power and low-end.

But for now I'll stick with a 1.6.


This is why I got interested in the T3 50 Trim. Thanks again for posting, this is about what I am looking for.


Greg (in the video above) is using another 2860 then I am referring to.

Let's get it all clear which GT2860R I am referring to and compare it to the GT2560R:

Turbo Part Number: 707160-7
CHRA Part Number: 446179-54

Garrett GT2860R: vs. Garrett GT2560R:
0.80 A/R Cold Side --- 0.60 A/R Cold Side
Inducer: 44.6 mm ----- Inducer: 46.5 mm
Exducer: 60.1 mm ---- Exducer: 60.1 mm
Trim: 55 ------------------- Trim: 60

0.64 A/R Hot Side ----- 0.64 A/R Hot Side
Inducer: 53.9 mm ------ Inducer: 53 mm
Exducer: 42.4 mm ----- Exducer: 41.7 mm
Trim: 62 -------------------- Trim: 62

Other specifications:
Turbine housing cast from high-nickel "Ni-Resist" material Turbine wheel is cast from "Inconel" material
for extreme applications Turbine housing has a unique "compact" 5-bolt outlet that is not interchangeable
with traditional T25 5-bolt outlets Bolt-on turbo for Nissan RB26DETT.

Compressor/Turbine map:






We can conclude:

Max rated BHP: GT2860R ~310BHP vs. GT2560R ~330BHP.
Max turbine CGTF: GT2860R ~15.7lb/min vs. GT2560R ~14.5lb/min
The GT2860R compressor can hold more pressure in the lower flow range then the 2560.
The GT2860R turbine could be more efficient, although the max efficiency is a useless number it ''could'' be more efficient.
The GT2560R has just a tad more top end compressor flow.

This is how I conclude spool-wise it will not differ very much since the compressors are almost the same but the 2860 turbine will flow just a little more and the wheel is 0.9mm bigger. The 2860 will be just behind the 2560.
These are some of the reasons I got so interested in the 2860. But there are also a few drawbacks vs the 2560.

But I have not decided on anything yet.

I want to atleast thank everybody for their .02 cents already

Regards

 

The compressor wheel of the 2860 you've selected is designed for high-boost, low-flow. Where the 2560 wheel is designed for lower boost levels, but higher flowrates. I'm going out on a limb here and going to say youre not looking to run 25psi.

While the 2860 turbine is more efficient up top, take notice at what PR each crosses the 10 lb/min mark. Considering the compressor wheels are the same size/weight, and the design of the wheels, the 2860 is going to have substantially slower spool without much gains up top. If you're targeting 250hp, look at where the compressor map stops at the 25lb/min mark -- on a 1.6L, the PR required to output 250hp is going to be roughly 2. Look how better suited that 2560 wheel is considering.

the 2860 on paper here seems like a bad choice, it's geared for a larger motor to spin it up, and then to run higher boost levels to output your power.

The 2560 is great on every 1.8L i've driven, it can spool fast and hit over 300rwhp. The 2860 only gives you a little top-end breathing in exchange for shitty boost threshold and lower area-under curve. I dunno why it would be considered on a 1.6L, let alone a 1.8L.


consider this 99 motor running a 2860:



my dyno on my 1.6L is better.


FM has done the comparison as well (keep in mind they used the 62 trim 2860): http://forum.miata.net/vb/showthread.php?t=445793







While that T3 50 trim has a turbine more similar to the GT28 series, the compressor wheel behaves more like a 2554.

 

Everything has been said already... 2860 is more efficient to some degree, but on your motor it's going to be a turrible experience unless you plan on staying around redline to get it to spool.

The 2560 will give you some low, and a whole lot of mid-high power all around. TQ will push the car and you will go quicker than the 2860 from a 2k rpm standpoint. You will be able to hit peak boost and have it through the entire rpm range where as the other may come on at a later rpm and make all of your low end a sad miserable old dog in pain that needs to be taken out and shot. From a 2860 user, don't do it... Unless driving over 100mph is what you want to do.

What rpm range will you be driving the car mostly in?

 

Thanks Brain, I just realised this myself too, I guess the way I calculated P/R ratio is way off or something. I have recalculated everything and now it seems to be a much easier choice.
The GT2860 is officially scrapped.

The reason it was introduced in my list was because of the higher efficiency and higher pressure ratio (which I thought I needed because of my faulty calculations).
One more reason the 2860 will be scrapped is because of the odd-ball ''compact 5-bolt exhaust'' (skyline OEM) pattern which is shitty to find a flange for.

Now on to the next

I think I'm going with a Garrett so the T3 Chinatarder is scrapped off the list so I won't enter the 50 trim party. Sorry to disappoint you Brain


Thank you sir for sharing your experience with the said turbo, and as I said above I stand corrected.

Now I will have to choose between a GT2554R or a GT2560R.

----- GT2554R
- Fastest spool
- Maxes out at ~250WHP
- Great for daily and autocross
- Craps out in top end

----- GT2560R
- Good spool
- Maxes out at ~300WHP
- More for track and higher RPM driving.
- More top end

Since I don't have a big race-track near me. And with regular daily driving I don't go above 5000RPM a lot.
If I'm driving my car hard on the countryroads right here then I'll be hitting red-line but It's really comparable to autocross.
A lot of turns and just sometimes there is a long straight.

I would say the GT2554R would be the best choice then.

 

A 2560 won't hit 300whp on a 1.6. At least I have never seen that done on a 1.6 miata. The 2554 is what you want to go with. It will spool the quickest on a 1.6 and provide the most power where you want it.

 

nitrodann did it, sort of:

 

We all know Australian dyno's read upside down and are not accurate. :P

 

 

Meanwhile on clubroadster, people are making 600whp with Mitsubishi ecu's.

 

All about that area above the curve

 

 

If I were to do it again, I would pick the 2554r over my current 2560r. There's just some scenarios during autox where I'm going too fast for 1st gear but too slow for 2nd gear, and I'm just waiting for boost to kick it. Of course, I'm just being super picky and complaining about < 1.0s (If I were to guess) of lag.

 

No, that's not the reason--it's because Australia is entirely peopled with criminals, and criminals can't be trusted.

 

Thanks for sharing mate, I know the miata doesn't do s**t under 3000RPM but after that I want it to pull. I am really considering the 2554 now although it won't have as much top end, but I think it wil feed my need for speed for a long time.

Regards