afr change from flat base to drop base filter

[vector1]

had something interesting happen when i changed from flat base filter to drop base. was trying to increase my field of view so thought i would try drop base filter. same size filter 4" x 14", same top.

afr at cruise went from 14.5 up to around 16-1. didn't know if something happened at the track or changing to straight through exhaust did this, so i put the flat base back on and the cruise afr returned to normal. the top i didn't think was very close to the carb inlet but it must have disrupted the airflow somewhat. wot didn't appear to change much that i could tell. anyway, definitely had not expected this. looks like the protrusion lives another day.

here's a picture with the flat base, the drop base was 1.5"-2" lower, same filter & top.

[jdean]

So you are back to the "Beyond Thunderdome" theme for a while

[vector1]

lol, haven't come up with a better one yet.

what's the word on your car? any pics of the scoop?

[jdean]

Hope to have some pics by tomorrow....if so I will post them here.

[danc30]

I would keep the drop base. Going from 14.5 to 16 means you are getting more air, better airflow. Not sure if you have a carb or FI, but I would richen it up either way.

I think this is an accurate assumption.

[vector1]

i hadn't thought of it that way. i figured it was a disruption of the airflow through the carb. thnx.

[jdean]

Makes sense to me. If AFR went richer it would mean less air getting through.