Fueling question

[ShannonSRT]

I found it weird coming off a Hellcat this doesn't show boost or AFR so I bought a P3 that reads it. WHY does a turbo'd motor not enter WOT till after 3500rpm and then only goto 12.3? That's literally a safe number I put on 392's NEVER a boosted car! I ran my Hellcat @ 11.6 WOT until I went to E and the it went to 7.8 on WOT.
Im wondering if I need to take it in?

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[Rensuhlo]

Forums have a search feature. Save yourself the new-person embarassment arc

 

[jmikes]

if you're having a heart attack at 12.3 afr don't look at JB4 logs running 14.5-14.9 AFR...

 

[FRSBRZGT86FAN]

I found it weird coming off a Hellcat this doesn't show boost or AFR so I bought a P3 that reads it. WHY does a turbo'd motor not enter WOT till after 3500rpm and then only goto 12.3? That's literally a safe number I put on 392's NEVER a boosted car! I ran my Hellcat @ 11.6 WOT until I went to E and the it went to 7.8 on WOT.
Im wondering if I need to take it in?

12.3 isn’t automatically “safe” just because that’s what you ran on a 392. A boosted motor is a different animal. You’ve got boost timing, IATs, fuel type, and the tune all playing into what AFR it should be at.

And the fact that it doesn’t go full WOT enrichment until around 3500 could be completely normal depending on the factory calibration and when the turbos actually start making real boost. But if you’re seeing 12.3 under actual boost, I’d verify it with a real wideband before assuming the car is happy.

Also, don’t compare the raw AFR numbers between pump gas and E85. 7.8 on E85 doesn’t mean it’s insanely rich compared to 11.6 on gasoline. Lambda is the number you want to compare

don’t judge a boosted setup by the AFR number you were comfortable with on a 392

 

[ShannonSRT]

12.3 isn’t automatically “safe” just because that’s what you ran on a 392. A boosted motor is a different animal. You’ve got boost timing, IATs, fuel type, and the tune all playing into what AFR it should be at.

And the fact that it doesn’t go full WOT enrichment until around 3500 could be completely normal depending on the factory calibration and when the turbos actually start making real boost. But if you’re seeing 12.3 under actual boost, I’d verify it with a real wideband before assuming the car is happy.

Also, don’t compare the raw AFR numbers between pump gas and E85. 7.8 on E85 doesn’t mean it’s insanely rich compared to 11.6 on gasoline. Lambda is the number you want to compare

don’t judge a boosted setup by the AFR number you were comfortable with on a 392

The P3 just gives AFR. I was saying I have tuned a 392 but I came off a 1100hp E85 Hellcat. My cruising AFR was 9.8 and 7.8 under WOT but yes I tuned by Lamda... .80 was my target with E

 

[razorlab]

392 and Hellcat uses old school port injection. I suggest reading up more about direct injection that the B58 uses.

OEM calibration on the Supra/B58 runs stoich at full load/boost until component protection kicks in. Tuned they run richer.

Most good ethanol tunes run around 12.6 AFR / .86 Lambda at WOT on ethanol mixtures, and low 12's/high 11's on pump gas on the B58.

Everyone new to DI freaks out at the AFR. Then they educate themselves.

 

[ShannonSRT]

392 and Hellcat uses old school port injection. I suggest reading up more about direct injection that the B58 uses.

OEM calibration on the Supra/B58 runs stoich at full load/boost until component protection kicks in. Tuned they run richer.

Most good ethanol tunes run around 12.6 AFR / .86 Lambda at WOT on ethanol mixtures, and low 12's/high 11's on pump gas on the B58.

Everyone new to DI freaks out at the AFR. Then they educate themselves.

Appreciate the knowledge I will do just that! Thanks

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