I sent this to Lee Bender at C&L, his response is below:
I recently installed the 76mm package on my highly modified 91 Mustang, I am hoping for low 11's this year all motor NA. My question is why is the stock air box needed? I tried the meter with my 12" K&N concial unit that I made a shield for to keep it away from fan wash. The car popped and ran pretty bad as soon as I replaced it with the stock air box it ran much better all around, is it due to the surface area of the filter? Do or will you have a air tube for 36# or 38# calibration. I need to upgrade my injectors and was looking at those to sizes and would love to keep my new meter.
Lee's response:
As long as the filter was shielded, you should not have had any
problem. We have other customers who run conical filters with this kit,
with no problem. We do have a calibration for 36/38 lb injectors. We
do not advertise this because most naturally aspirated applications will
not require that much fuel.
Your factory airbox with the panel filter flows 800-850 cfm. This is
enough air to support more than 700HP naturally aspirated. If you have
any other questions, please call.
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