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sperry · 2013-06-14, 01:15 PM

Here's the approximate layout of the radiator (blue), oil cooler (orange), and intercooler (red). The black lines are the body/bumper/shrouds in the top-down view. I super-imposed the boxes on a picture of the car so you can get a feeling for how the air is entering the cores (I don't run at the track with the lights installed, but the supertones are on there still).

If I were to build an air box, it would basically mean cutting the bumper and front grill out and extending it out and away from the body. Much like GST did on an earlier version of their Time Attack car:

That's not something I'm really keen to do. A splitter would be nice, but as it is, the car needs more rear downforce in the high-speed stuff... a splitter would mean I'd need an actual functional wing on the back of the car to keep it pointing the right direction in the RFR esses, which is like $1000 for something decent.

I think I need to focus on lowering the pressure in the engine bay. The new extractor hood should help. I haven't had a chance to drive the car at speed since we put it on... and I should probably avoid 100+ mph until my hood pins arrive.

Here's another car with the same hood to get an idea of the extractor:

The vent in the hood is about 14"x2", give or take, and positioned directly above the gap between the radiator and the motor. I replaced the stainless steel mesh (that probably blocked 50% of the area) with some cheap-o "gutter guard" plastic mesh (that blocks more like 1% of the area).

Short of aerodynamic testing of various undertray shapes, or possibly relocating the oil cooler to a fender and figuring out airflow there, or getting a $4000 v-mount, I'm out of ideas.

2013-06-14, 01:15 PM	#37
sperry The Doink Real Name: Scott Join Date: Nov 2002 Location: Portland, OR Posts: 20,335 Car: '09 OBXT, '02 WRX, '96 Miata Class: PDX/TT-6 The way out is through	Here's the approximate layout of the radiator (blue), oil cooler (orange), and intercooler (red). The black lines are the body/bumper/shrouds in the top-down view. I super-imposed the boxes on a picture of the car so you can get a feeling for how the air is entering the cores (I don't run at the track with the lights installed, but the supertones are on there still). If I were to build an air box, it would basically mean cutting the bumper and front grill out and extending it out and away from the body. Much like GST did on an earlier version of their Time Attack car: That's not something I'm really keen to do. A splitter would be nice, but as it is, the car needs more rear downforce in the high-speed stuff... a splitter would mean I'd need an actual functional wing on the back of the car to keep it pointing the right direction in the RFR esses, which is like $1000 for something decent. I think I need to focus on lowering the pressure in the engine bay. The new extractor hood should help. I haven't had a chance to drive the car at speed since we put it on... and I should probably avoid 100+ mph until my hood pins arrive. Here's another car with the same hood to get an idea of the extractor: The vent in the hood is about 14"x2", give or take, and positioned directly above the gap between the radiator and the motor. I replaced the stainless steel mesh (that probably blocked 50% of the area) with some cheap-o "gutter guard" plastic mesh (that blocks more like 1% of the area). Short of aerodynamic testing of various undertray shapes, or possibly relocating the oil cooler to a fender and figuring out airflow there, or getting a $4000 v-mount, I'm out of ideas. __________________ Is you is, or is you ain't, my con-stit-u-ints? Last edited by sperry; 2013-06-14 at 01:17 PM.