So this weekend I decided that id have a go at the rear bumper. First thing I did was hole saw 3 1/4 holes in the center of the two scoops that come down from under license plate. From the looks of it that's where most of the air would be scooping up from the underside of the car. I then measured inch tall and 6 inch long square blocks and drilled the corners to get them started. I first tried using a small hand held hacksaw with a metal straight edge gorilla taped to along the line. This worked alright but was SLOW, I got half a hole done in a hour and still had five and a half to go. not gunna work. With hands cramping I opted for something with for mo-powah and bust out my angle grinder with a metal cutoff wheel and traced the holes in sharpie. Being very careful I was able to cut the rest of the 6" lines in about 5 mins flat and used the small hack saw to cut the 1 inch verticals. Once the holes were in the bumper it was a matter of filing down some small burs.
I ended up using some truck door liner cut and fitted onto the perimeter of the new holes. This took some time and for the most part was just eyeballing the sizes and angles needed. it was getting late and cold in my garage so these are just 'good enough' for the next few track days. I've already started to make a sort of a jig so ill be able to cut another set of hole liners with a more factory fit and finish.
heres a couple pics i quickly snapped, I meant to get some better ones but since the car currently has no battery and pushing it out into the rain didn't sound like much fun so that'll have to wait. anyways for now..
Who knows if it will actually make a difference, i've got no real way to quantify it except for some some backyard logic. Ill see and report back since I've got quite a few track days this month at some of the faster tracks out here in SoCal. Regardless it does look a little more 'business' and since my bumper was less than perfect anyways- that's a bonus in my book.
