November 02, 2020, 06:03 PM
00 DEAD ONHead flow/fuel consumption
If your BBC head flows 460 cfm will it need more fuel than a head that flows say 410
Thx in advance
November 02, 2020, 06:15 PM
sr4440if you don't give it more fuel, it's going to be way lean.
To the math we go!!!!
410 cfm x 2.2 = 902 hp 460 x 2.2 = 1012 hp
902 hp / .5 BSFC = 450 pph 1012hp / .5bsfc = 506PPH
so roughly 12% more fuel
Joe
November 02, 2020, 06:45 PM
BJs Wild RidePretty sure I’ve seen bsfc go down as the head gets better.
How is that possible? I dunno, increased VE results in higher dynamic compression and therefore better thermal efficiency... who knows
Now, if it’s mfi and you’re setting a baseline tune i sure wouldn’t bank on that. But I also wouldn’t be shocked if it makes more power on similar pfuel flow.
November 03, 2020, 09:08 AM
TOP38quote:
Originally posted by 00 DEAD ON:
If your BBC head flows 460 cfm will it need more fuel than a head that flows say 410
Thx in advance
Is this a trick question!!!!!!
As with most open ended questions like this the answer is it depends!
But assuming you use the same combo, run it the port the heads and reinstall them,,, using a carb, no you don't, the carb will listen to the motor so the more air that flows through it, the more fuel it will send to the motor. This assumes that the rest of the combo can use/utilize the added airflow! If you had a MFI setup then you may need more fuel.
November 03, 2020, 09:09 AM
TOP38quote:
Originally posted by sr4440:
if you don't give it more fuel, it's going to be way lean.
To the math we go!!!!
410 cfm x 2.2 = 902 hp 460 x 2.2 = 1012 hp
902 hp / .5 BSFC = 450 pph 1012hp / .5bsfc = 506PPH
so roughly 12% more fuel
Joe
Not that simple.