After my fresh engine rebuild, I was equipped with a Turbonetic Journal bearing Turbine wheel 65mm .81 AR . At idle I was seeing roughly 13 AFR.

But after upgrading the turbo to the GTX3582R Turbine wheel 68mm 84trim with .82 AR. At idle I was roughly at 11.. sometime it wouldn't read at all.

Is this normal? I just hope I didn't have an issue with my injectors.
Just want to know before I calibrate a new map.

Same manifold, downpipe, same tune. Only thing that got swap is the Turbo.
At idle I'm still seeing 40psi on my fuel pressure.

Setup:
1050x/2000cc ID injectors.
Ran in parallel
450Walbro

Here is my fuel map

 

I just went through something similar, and it affected everything, 362 sxe to 8374 efr. you have to re tune.

 

You might have a different issue if you couldnt see the AFR though.

 

Cancel.

 

Sorry for the miss communication when I mention "sometime afr doesn't show at all"
Well my old AEM gauge only read from 11-17.. so sometime when it's super rich it won't even show it on there.. but then blip into 11.1 ~ 12 when I open the throttle a bit.

I will see if I can get the Basemap adjusted. for better result.

 

ahhh okay,

Ahh okay, cause I don't even have my intercooler pipes fabricated it yet. It's just running open air right now for idle.
But I guess easier flow could affect the AFR/oxygen sensor.

 

Remember, you didn't just swap out the bearing from journal to ball bearing (keeping same wheel and housings). The whole turbo changed, correct? The housings and the wheels and the bearings, it's a whole new unit. Even if it was just a different wheel and bearing you could even expect some changes.

The turbo is spinning at a different speed, producing different airflow from the compressor side. On the exhaust side backpressure and pulsation are different, which affects residual gas in the combustion chamber, which can affect AFR and combustion speed. A turbo engine is basically two air pumps bolted together, and you just changed one of the air pumps.

 

You changed turbos completely. You need a new tune.

 

As of right now I’m still on jack stands, I’m def going to get it professional tune shortly after I work out all the kinks.

but what I did yesterday was a Injmap scale down through correction, so here is what happen:

1.00 correction - AFR = 11 sometime dip lower
0.90 correction - AFR = 11.4
0.80 correction - AFR = 11.4
0.70 correction - AFR = 11.4
0.60 correction - AFR = 11.4 attempt to rev up. AFR shoot up above 15 and died.

going to hook up the WB to the Datalogit it and attempt to run another map correction later.

any suggestion?

 

injectors need to be set up right in the datalogit with the lag tables etc. also, make sure your injector atomization port is not blocked off.

 

agrhx,

At first my fuel atomizer line was plugged. But after your suggestion I went to uncapped the fuel atomizer line. But still it didn’t affect the AFR. Going to dig into the base map here shortly.

I also wired up my AEM WB, however my WB only read from 11-18AFR... but during the map trace it only show 0 in the cells. I must have done something wrong in the AN1-AN2 setting.

 

Two completely different turbos. You will need a retune.