Begi Churbo vs. GT2554R
 

-CONSTANTS-
The Dyno (Advanced Engine Dynamix in Orange County, Ca)
Stock 1.6L @ 200,000+
Fidanza 7lb Flywheel
ATI Super Damper
MS2PnP
750cc Injectors (Sequential)
340LPH Pump
5-speed / 3.9 Torsen

-GREEN-
Begi T25/T28 Churbo
91 Octane
2.25" - 2.5" catless
EBC @ 14.5psi

-RED-
Garrett GT2554R
E85
2.5" catless
EBC @ 13.5psi
LS Truck Coils

Needless to say the GT2554R is A LOT more fun. The car really likes more timing the the E85, it made 245whp with more boost and less timing but the power is smoother with more timing and less boost. I know she's close to the limit but I really want to see what it can do, and still withstand some torture. Plus Quinn Kizis and Tom (Tom's Turbo Garage) made 254whp and 252whp on stock bottoms... Autocross is only 70-80 seconds at a time so it gets to cool down after quick beatings. I LOVE the powerband on this car. It's also daily driven, I'm not sure what everyone is getting here as far as MPG on E85 but I managed 25.7 highway on the way back from the dyno yesterday, seems pretty good. Cheers! :party:

https://www.miataturbo.net/attachmen...ine=1440344242
https://www.miataturbo.net/attachmen...ine=1440344242

That's a very healthy improvement in the midrang,, Congrats

It's like a different car. In a sense I'm glad I upgraded to the Garrett later so I have a real appreciation for it, haha.

Very interesting.

I wonder how the power would compare had they both been on the same fuel and boost.

Even if you drop the entire e85 run 20hp the gain in midrange pre-4K would be more than worth it. Like a whole nother' thousand or more rpm of powerband where it's fun for the street.

Looks wicked fun!

This is one of the reasons I am swapping to a "real" turbo. Looks like a fun car :) cheers for the post

exactly what i'd expect.

the "2854" is the stupidest turbo ever: it spools like shit and makes shit for power.


I think if you were able to pick up an auto cam, you get even better response with a mid-range bump and still the same peak HP.

It does seem like a bit of a turd. Who wants a small compressor and a big turbine?

I currently have this turbo on my 1.6L Honda. Ill be curious how it acts once I have it sorted out.
Finding a Nissan Garrett T28 is on my list of upgrades for sure.

BUT GUYSSSSSSSSSSSSSSSSSSS

BEGi says it's a great turbo :giggle:

And actually, some cars (like subaru's) really tend to like bigger hotside/smaller compressor type turbo's

there's nothing wrong with a big turbine and smaller compressor if it actually performs.

the T3 50 trim has a very similar compressor wheel with a much larger turbine and outperforms that turd in all areas.

Yeah I realize how bad it is now... the Garrett just easily outruns it at all RPM. Even on the baseline pull with the 91 octane timing map it still made 240whp and way faster torque production. Excuse my noob-ness, but are you referring to an auto intake cam or exhaust cam? Or both?

It must just be a crappy wheel design or something.

auto intake cam.

that was the one mod i never did that I really wanted to. much better profile for mid-range grunt and boost.

Awesome, thanks. I'm building a [zips up flame suit] 1.6L in an engine machining class I'm taking, so I'll definitely be on the hunt for that cam to use. You don't think the lower lift should affect the top end power too much? Would a cam gear on the stock manual cam be more beneficial to reduce overlap but keep the higher lift?

If you did not have an awesome youtube channel I would probably ban you for such nonsense.

YES Immunity via the power of YouTube. I'll try not to let you guys down. :D

You're only going to let yourself down.
But who cares, build it, crank up the boost to ALLOFIT, and it will probably be silly fast either way.

^ That's the spirit. Besides, when I finally see the light, all it's going to take is a different set of pistons. I'm not going to put any money into headwork or cams on a 1.6L, so I'm really only going half retard. Even if I only get the same powerband I have now, but know in the back of my mind that my rods aren't on the verge of vaporizing, it will be worth it.

I don't think an auto cam is a worthwhile mod. I think Brian might have the right idea, but the auto cams kill the top end dead.

https://www.miataturbo.net/dynos-tim...-update-85138/

That's my setup (manual cam) compared to a very similar setup, only with an auto cam that soon switches back, power then matches mine...

need real dyno comparisons. the auto cam shouldnt drop off until at least 6K.

Ive seen one a long time ago one a greddy kit, ill try to pull the before and afters.


the auto cam should gain responsiveness and provide a huge bump between 3 and 5k.