Ronny

iTrader: (1)

I recall seeing a post here recently of a need for much more fuel(high max BLM) at or about 1400 rpms under light load and with a cammed engine. And the accompanying lean condition.

I too have observed this situation with my current cam 224/230@.05 with 350 cid. I have currently 100% VE in that area 1400 rpm 40-70 MAP and much lower fuel at higher RPM . Previously I had pulled out that high VE to smoothen the table and it got much worse lean bog.

My logs show BLM at 172 for 1400 and 1500 rpm same MAP above.

I was going to change the BPC/VAC at those MAP values but the situation does not exist over 1500 rpms so decided against.

During log the air flow is low at 65 grams/sec (+ or-). seeing that the air flow is low it may be a lack of vacuum and fuel falling out of atomization. WB is 18/1 and NB reads min V.

Or could it be the overlap allowing the exhaust to pollute the combustion chamber leaning the mix.

Or could the proportional gains need to be reduced further? I have then at 50% of stock L03 levels. I have 75 lb injs at 20 lbs fuel pressure.

What caught my eye today was an article in CHP suggesting Quick Fuel/ECU has addressed the stumble issue which I believe is lean. They have a table for off idle A/F which they suggest helped. I suspect that table is AE which will help with a change in >TPS% but not steady cruise.

I ruled out OL for my fix as lean occurs at cruise 25-40 mph in any gear(manual 4 speed).

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