If this appears as a text-only FAQ, click Here
for the photos to make this page a VFAQ.
Above: 1.5" center/1.0"
side ground clearance Front Air Dam on the Bonneville
Salt Flats in 2006.
This modification is a
quick, easy, and very effective way to dramatically
increase front downforce and high-speed handling on '95 & '96
Talons and Eclipses. The huge amount of extra downforce at speeds
above 100mph make the car feel like its absolutely glued to the road or
racing surface; which these cars really need as they tend
to develop undesirable lift characteristics above 100mph in stock
form. This air dam has been tested at off-road racing speeds
above 145mph with absolutely no flex or distortion. The techniques and
air dam sizing can easily be adapted to fit other stock and lowered 1
& 2 G's; and is done with the vehicle on the ground. The only
question is: How low can you go?
Check your local and state ordinances about ride and bumper
heights prior to installation. The author is not responsible for any
failure or accident in any way related to the design, manufacture, or
installation of similar parts developed from the ideas or
techniques described herein on any motor vehicle licensed to operate on
any public or private roadway or in any off-road usage. *These designs are intended for DSM applications only! Any
other usage is bad Karma ~:^(
on the '95 TsiAWD above, and a '95 Eclipse GSX, revealed
that a 3.00" ground clearance was as low as we could go
on the "paved roads" here in Colorado (with moderate to severe
daily scraping). Front bumper covers/air
dams/bras are considered to be wear items in Colorado!
Racing at Bonneville in 2004,
I fabricated this front air dam with a 1.0" Front
& Side ground clearance as shown below, but the front
edge bottomed-out under braking:
On the plus side, this
air dam uses extremely-durable and very-inexpensive
materials from your local hardware mega-retailer, its resilient enough
to put up with major off-road abuse(hehe); and, it can easily be
replaced for <$10 if you munch it on a speed bump or
curb. This airdam is way more durable than any
aftermarket fiberglass bumper cover will ever be!
82" of 6" wide
professional-grade lawn edging (sold in 25' & 50' rolls at HD).
of 18 ga. 1.25" x 1.25" slotted steel angle.
10 ea. 3/8"
Stainless steel "Snowmobile" rivets and backing washers.
1/4" x 3/4" bolts and Nyloc nuts, or metric equivalent.
Re-use all the
factory 10mm bolts along the lower edge of the bumper cover.
carriage bolts and 12 Nyloc nuts can be substituted for the rivets
3/8" drill bit, drill
tin snips or hacksaw
rivet tool -or- wrenches
sharp utility knife
Before you start:
Place the car on a level surface with all tires inflated to spec. and
with normal weight distribution and ride height; i.e., if you weigh 150
pounds, place 150 pounds in the driver's seat before taking
measurements and fabricating the air dam. If you carry around a
passenger regularly, also add their weight to the seat they usually sit
2) Park the vehicle, with
the safety brake engaged.
3) Wear safety glasses
when drilling. Wear gloves when cutting.
1) Remove the seven
10mm bolts along the bottom edge of the front bumper cover, and set
aside for re-use.
2) Straighten the
removable metal bumper flange if necessary.
Cut nine 6" sections of slotted angle, and two 3" sections,
with a tin snips or hacksaw. Locate the center of each section at a
slot or hole in the angle bracket when cutting.
4) Paint leading edges of
angle brackets w/black paint(recommended, not required).
5) Enlarge the hole in the
top edge of the slotted angle for clearance for the factory lower
bumper cover bolts if necessary.
Starting in the center, replace the 10mm bolts through
the center hole in the slotted angle, so that the vertical side of
the bracket is facing toward the leading edge of the car.
to each outside edge, install a 6" section of slotted angle
centered on each of the factory-tapped bumper cover holes.
Approx. 4" in front of the wheel opening there is a factory
hole in the bumper cover. Place the 3" section of slotted angle
above the plastic bumper cover flange as a backing plate above
these holes; and secure the angle brackets and bumper cover
together with a 3/4" long bolt and nut.
Fabrication of the Air
1) Measure the ride
height(rh) of your car.
(ground to lower edge of
bumper cover at car center).
2) Determine the ground
clearance(gc) you desire.
Subtract the ground clearance from the ride height. This is the
width(height) of the air dam you will cut from the lawn edging.
Example: 7.25" rh -
3" gc = 4.25" air dam height
Use a utility knife and framing square to cut an 82" long piece of lawn
edging. [Wear the work gloves to avoid cutting yourself.]
4) Use the knife and
square to cut the edging to width.
5) Use a pencil to mark
the center point of the 82" length.
6) Trim the height of the
lawn edging down to the pre-determined center air dam height along the
entire 82" length.
Hold the air dam up in place against the bottom of the bumper cover in
front of the flange at the center point and drill a 3/8" hole through
the edging and flange at the marked center point; and temporarily place
a rivet or bolt through this hole to hang the air dam in
8) DO NOT
crimp/tighten the temporary fasteners.
Working from the center, pull the edging taught to each side, and mark
and drill a 3/8" hole from under the car through the
edging at a hole near the center of each proceeding slotted
flange. Temporarily place a rivet/bolt through each of the holes
you've drilled in the edging and through the slotted flanges to
hold the air dam up in place. Stop drilling about 2' out from the
vehicle center where the bumper cover starts to wrap back around
towards the wheel opening, and mark or tape a vertical line on the
airdam and bumper cover below the outer edge of the bumper cover
wheel openings on '95-96's are about 1" lower than the center of the
bumper cover, so the air dam height must be tapered down as it wraps
around towards the wheelwell openings. Remove the temporary
fasteners from the flanges and set the airdam aside.
Place a piece of cardboard vertically from the side of the bumper cover
to the ground, and then scribe a line on the cardboard that
follows the taper of the bumper cover from the lower air ducts to the
wheel openings. Cut out these templates. Align both side
templates to the air dam, transfer the lines onto the air
dam, and then trim down the width. [Do
not trim off the long ends extending past the wheel
openings at this stage].
Re-mount the air dam to the flanges with the temporary rivets. Check,
align, and retrim the air dam, if necessary, to fit tightly
along the bottom edge of the bumper cover. Mark and drill the
holes at the remaining flanges, and place rivets or bolts through the
airdam into the flanges.
at the center, place a rivet backer/washer on the back side of the
slotted flange bracket and crimp the rivet, or tighten the nut/bolt.
Working out to the edges, tension the edging, place a backer washer
on each fastener, and tighten the air dam to the slotted
15) Finish by
marking and cutting the long ends off at the front edge of each wheel
opening. A plumb/vertical end or a slight
angle towards the rear looks best.
16) Enjoy learning new
approach angles and ultra-slow speeds at driveways and across speed
the above descriptions, you can see that there are several potential
improvements and variations which typically would add to the
project's minimal cost. Unlike spendy
aftermarket bumper covers, this inexpensive trick front air dam
will withstand a substantial amount of abuse both on and off-road!
it snows where you drive, and you don't feel like playing snow plow,
simply remove the 10mm fasteners from the lower edge of the bumper
cover to remove the entire air dam assembly. Re-mounting takes just a
few minutes! The best part of this aero mod is that complete
replacement of the all the airdam components costs less
those seriously inclined towards achieving maximum aerodynamic
downforce, side skirts could conceivably be fabricated from the
same edging, and installed along the factory unibody seams with
additional brackets. This application would require several
modifications to the skirts and/or your jack for jack
2001-2007 by James LaMere. All rights reserved.
...and, be sure to check out http://co.dsm.org
Home of the fastest
high-altitude DSM's on the planet!!