Track next sunday...fuel question.

[87NAT]

I am finally heading to the track next week to test new turbo(6776dbb) and engine combo.

Just made some WOT test runs and I have a question. Heres what I got:

In the top of third on my first pass I recorded a low 02 of 746 and 4.5 degrees knock on scanmaster and 10.8-11.1 A/F on wideband. Alky was at 6 so I moved it to 7 and made another run. This pass was 754 02 count and 0.0 knock and 10.9-11.2 A/F on wideband.

All runs are at 42 # of FP static and 22-23 psi of boost. 24.1 degrees timing 1/2 gear and 21 degrees timing in 3/4 gear. I have 13% of fuel aded to WOT on my TT chip. The car feels great and is kinda scary...really gave my brakes a good work thru.

Heres the question: Why is the 02 count low and my A/F right on target? Should I be adding more fuel to WOT?

 

[Razor]

This assummes your using an AC Delco AFS20. If so, sounds like your lean.

You shouldnt have to be adding that much fuel, if anything you should be pulling fuel.

Remember start rich and work your way lean. By your descript, It would suggest that your lean. Bring the AFR down to 10.0 and have it where its not adding fuel.

Hope this helps

Julio

 

[87NAT]

This assummes your using an AC Delco AFS20. If so, sounds like your lean.

You shouldnt have to be adding that much fuel, if anything you should be pulling fuel.

Remember start rich and work your way lean. By your descript, It would suggest that your lean. Bring the AFR down to 10.0 and have it where its not adding fuel.

Hope this helps

Julio

Julio thanks for responding.

Did I misread your post. You say it sounds like I am lean but then you say I should be pulling fuel. Is that what you meant or a mis-type. I would need to add fuel to get the A/F down in the low 10's and bring up the 02 counts.

Or maybe when I pull fuel and leave the alky setting alone it will bring down the A/F???

Let me know.

ED

 

[Razor]

I have 13% of fuel aded to WOT on my TT chip.

Ok.. see you posted having to add fuel. So that means your lean. If anything you should be pulling fuel since the methanol is a fuel. Does that make sense?

Bring the boost down and figure out why the car is leaning out... You shouldnt have to be adding 13% fuel especially with alky spraying.

 

[87NAT]

When I ordered my TT chip for my turbo and 60# inj upgrade I told Eric I was putting a 6152 turbo. Between the time the chip came and me ordering the turbo I had decided to get the 6776dbb. I had forget to reorder the chip for the the 6776.:redface: I emailed Eric and he told me to just add some fuel at WOT. He felt that I should have plenty of room with his plus/minus 20% fuel adjustment in his chip. Hence the added 13% at WOT.

 

[Black Power]

Keep us posted on the times, I am looking at that turbo myself

My buddy gave me a ride in his GN with that turbo and it scared me to death @ 16psi, I can't imagine 24 :biggrin:

 

[TURBO 6]

Ed, when you go to the track take the boost down to 20 and work from there. If all's good at 20 start going up with the boost. I think you're too lean with the current tune.

 

[Eric Stage I]

When I ordered my TT chip for my turbo and 60# inj upgrade I told Eric I was putting a 6152 turbo. Between the time the chip came and me ordering the turbo I had decided to get the 6776dbb. I had forget to reorder the chip for the the 6776.:redface: I emailed Eric and he told me to just add some fuel at WOT. He felt that I should have plenty of room with his plus/minus 20% fuel adjustment in his chip. Hence the added 13% at WOT.

Hi Ed,
You must've forgot, I revised your chip for the bigger turbo already. The chip should have a "B" on the label. We did that last December.
Those 67 turbos make a lot of power at low boost. Since the alky system is spraying based on boost level, you might have to bump the knob up a little. Work back an forth between fuel and alky to find what works best.

Regards,
Eric

 

[Razor]

Ed, when you go to the track take the boost down to 20 and work from there. If all's good at 20 start going up with the boost. I think you're too lean with the current tune.

+1

 

[87NAT]

Eric, between work and the kids my time for my car is a few minutes a week it seems like. I completely forgot about the extra chip you sent.:redface: I guess I am getting old...

I was fighting detonation with the new engine back in November/December and I assumed it was the chip but it turned out to be a bad PCV sucking lots of oil into TB hence causing lower octane and lots of knock retard. The new chip you sent didnt help at the time because it was just adding so much more fuel to an already existing problem.:redface: I pulled it out and went back with the old chip and stuck the new one on the shelf. I am sure that now the PCV issue is fixed I can put the "B" chip in the car and I will be back to adequate fueling from your default settings instead of maxing out the current chip. Thanks for reminding me.

I will post the track results next week. Thanks to all who responded.:smile:

 

[John Wilde]

Good luck man!