Hi everyone!

Well I have been getting squashed by the admins at scionlife over a front bumper mod I have done for scientific reasons to my front bumper.

Lemme give you some background-

I bought my XB at Christmas time, for a while after driving it I smelled very hot rubber when exiting the vehicle, I thought it smelled a little like coolant so I took it in to the dealer who pressure checked the system and said nothing was leaking- after this I was relieved until I pulled over that day and got out of my car and the same strange hot-rubber and plastic smell was there.

After thinking about this for a while and examining my engine and radiator I realized that it was the front bumper blocking the airflow into the engine compartment. This was made very evident by the oily dirty stains on my radiator that only went up about 27% of the way from the bottom of the radiator which meant that the rest of the air was being deflected somehow by the factory grill and bumper assembly.

After examining the angle of the deflection on top half of the front bumper, I realized what was occurring- the air was not being allowed to enter the front grill at highway speeds effectively by the angled air being deflected by the top half of the bumper and when it passed sideways across the "holey grill" it just passed over the grill holes instead of through them. The top half of the radiator was showroom clean, while the bottom 27% was road stained. The hole pattern seemed to help this effect along by creating something in the aerospace industry known as VC's or Vortex Creators, channeled walls of resistance that create a V pattern across the grill and set up channels of resistance to air entry. Now either this was a huge mistake in styling or a really good design for automation controls failure.

I calculated that the plastic blunt-nosed design had to be modified or all the sensors and wiring in my engine compartment might get hosed by the heat build-up which is what was causing the smells. I noticed the engine compartment was sealed almost entirely, with rubber gaskets and closed fenders and the exhaust manifold set in the middle like a HUGE heater cooking all the hoses and wiring around it which are already hardened and softened by the heat exposure after only 6500 miles!!

I recommend that the hood directly above and extending back from the exhaust manifold be louvered to let the heat escape up and out of the engine compartment as well, well mainly because heat rises, lol.

I measured out with a dry-erase marker, and left myself 4cm down the middle for plastic bumper lip support cut 2 holes as neatly as possible leaving 1cm of material around the edges for trim, calculating the angle of air entry past the holes and just big enough to directly hit the radiator with cooling air at highway speeds. The two holes had a forward-facing profile of 28cm x 8cm which would allow 1.1 million cubic cm (or 38.8 cubic feet) per second into the engine compartment per second at 55 MPH.

Did I mention that I am a scientist?

Anyways- I tried out the "MOD" for 2 days and the smells dissapeared entirely. Now the admins from the other site said this was due to additional air, and now I gotta say he's right, it is a lot of additional air right where it's needed most.

I will post diagrams of the mod sometime today with details on measurements.

I have not put "grill" material over my holes yet- I haven't found any that don't block the airflow, maybe I'll channel the two holes with a "scoop" look in fiberglass or just trim the holes in black rubber edge trim.

Free the XB, make it the longest lasting, coolest car on the road!

Zio

Welcome to the site and thank you for posting your findings. While I haven't experienced the heat or smell issues, I do appreciate the effort you've put into solving the problem for yourself.  I look forward to seeing pictures of the completed project

HI guys thanks for waiting, here are the pics for the mod when I completed it.




I also made a kit to sell to others who want this mod.

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&sspagename=STRK%3AMESELX%3AIT&viewitem=&item=280224852314

Zio

Forgive me for sounding dumb. But are the 2 mesh sections on the front the MOD?

Well that makes sense. It looks awesome. This is something I would be interested in. I have checked the ebay listing and just might be doing this. I don't want issues down the road.

I think that they would look cool with some backlighting for the night time.

Very cool!

Well let's hope this works, or even that I put it in correctly   cause I just bought one!