BarbyCar

iTrader: (1)

http://www.pbase.com/klin/image/135685208

I had an extra cover so just to experiment I cut it up. With it, ODB2 on my 2000NB showed a 4C coolant temp reduction at the end of the back straight at Shannonville Motorsport Park. (Back to back runs with it taped over and open).

timk

Interesting!

TorqueZombie

iTrader: (6)

Stupid question. How'd you get the cuts even. Been looking into this kind of thing and terrified to go dremel crazy on my only bumper.

pusha

iTrader: (5)

I'm just gonna go out on a limb here and guess he used a stencil

BarbyCar

iTrader: (1)

Yes a stencil was used. I based the pattern on the hood extractors from late 80s Group B Opel Manta Rally cars.

The cuts were done using a 1" wood (spade) bit joined with a Dremel fitted with a reinforced cut off disc. Then sanded smooth with a Dremel 1/2" drum sander. I cut up a cheap mouth grill and glassed it in place behind the holes.

The plastic cuts very easily, just take your time. I figured using smaller holes instead of one big one would preserve some of the structural integrity - it seems pretty strong and stood up well to my last lapping day at Mosport on the big track where it saw 110+mph on the back straight.