dustinb

Just got back from a baseline on a dyno dynamics machine. Very happy with the results. Here's what the build is:

AEM EMS
Godspeed GT28 Turbo (link in signature)
Flying Miata DIY cast manifold & 2.5" Down pipe
2.5" Test pipe
Topspeed Pro-1 2.5" catback exhaust
RX7 460CC injectors
Yonaka FMIC and 2.5" charge pipes
M-Tuned dual feed fuel rail
1997 1.8 miata motor
AEM 2 bar map sensor
HKS internal wastegate actuator

I think that's all the important stuff. I was running about 14psi on the run. I'm posting HP/Torque ad AFR/PSI.

dustinb

Compare that to the Chinacharger GT2870 vs Garrett GT2554 with Dynochart thread. China rules

Braineack

iTrader: (62)

that's sized like the 2871 fwiw.

18psi

iTrader: (76)

That is great for only 14psi IMO. Full toruqe at 4k with no big taper despite a basic setup. very nice.
Congrats.

Is the dip in afr before full boost to help the turbo spool up?
Its pretty conservative on the afr side.

Can you post spark map? Or pm me?
thanx

PS: I enjoy my godspeed very much also

dustinb

I'm just heading to work but I'll post up the fuel and ignition maps tonight. Thanks guys

miatauser884

iTrader: (11)

In for timing map

chicksdigmiatas

iTrader: (11)

I will probably be grabbing this turbo, great numbers for 14 psi. Do you have internal work? I wouldn't mind seeing your tune either. I need to clean mine up.

elderc

Great numbers !

dustinb

Sorry for the crappy resolution but I don't have my ftp login information on my laptop so I have to use crackbook image hosting.

Ignition map


fuel map


Thanks guys I'm really happy with the numbers. Somewhat concerned too. And the motor is totally stock. It might be time to think about buying a spare and building it up.
One more thing, this is on 94 octane fuel. We have 94 at the pump.

miatauser884

iTrader: (11)

I couldn't get them to embed either

It may be something i can't access at work.

dustinb

Should also mention I have an HKS internal wastegate actuator on this thing. It's an 8psi gate and I'm using the AEM EMS with a GM boost control solenoid to control boost.

elderc

94 octane is that @ Petro Canada ?

miatauser884

iTrader: (11)

Is the left hand column psi? I'm trying to make sense of the numbers. Unless there is a multiplier, it seems like very low timing in the vacuum region. Then it abruptly drops entering boost, and continues to increase to the advance target at max boost.

I'm trying to compare to mine:



I'm considering lowering my higher kpa timing values for a safety margin.

Best run was 288/256 at 19.2psi. Yours is looking great at 5 less psi. It appears that my clutch was not holding, so I have to get it back on the dyno here in town. Maybe my numbers will be better. It was strange when mine was being tuned. After about 15psi, I stopped seeing major gains as psi increased.

dustinb

No Petro Canada stopped carrying it. Chevron has it though.

The left hand is in PSI. I haven't done really any vacuum tuning at all. My power went way up with my new exhaust. Having it breath just made all the difference. As far as timing goes, I have read things saying that timing should always increase, so I made my in boost portion always increase. I figured I'm rarely going to boost at like mid way, so why not have it increase up to my peak? That seemed to help quite a bit. I did all my fueling by data logging and just seeing how it was firing, adjusting, and more data logging.

My clutch is an ACT HDSS and it's only rated at 234torque, and I think that's at the crank so we'll see how long it lasts.

18psi

iTrader: (76)

That is CONSERVATIVE timing
Which makes this even more impressive.

I wouldn't worry about the motor too much with that timing unless something goes horribly wrong.
good stuff man

dustinb

Hey thanks I was really surprised. First run was 254 but I was pretty lean up top. Fattened it up a bunch and the second run was 250. I took a bit out and we let the car cool down. It then laid down that. I was in shock and so was the dyno guy. There aren't too many modified miata's up here but I am now the highest horse power one. Below me is a 258hp ford v8, then a 230hp modified MSM.

miatauser884

iTrader: (11)

i was very surprised with your timing numbers. ill throw mine on the dyno again. this may prove that there is a suprrior china 2871. Good stuff!

shlammed

iTrader: (8)

you need to have your car tuned properly.... i bet it feels funny to drive...

the massive drop in timing at atm pressure would feel funny street driving.
should be able to gain all kinds of drivability with a good tune.

that being said, your numbers are cool.

18psi

iTrader: (76)

The difference between your numbers and his is pretty drastic. 280 on 20psi vs 260 on 14 with much less timing

I wonder what Savington will think of this

miatauser884

iTrader: (11)

I agree. I'm hoping that the dip you see in the dyno pulls (in my build thread) is due to the clutch slipping and the regrabbing. It will be interesting to see what the pulls are here locally with a new clutch.

His timing numbers are so unbelievably passive that it may be that the turbos are very different design-wise.

This may be a good thing.