Difference between revisions of "Exterior"

Revision as of 21:33, 24 November 2011

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Tow Hooks

Not allowed to remove the tow hooks. Asked on miata.net if anyone knows of any packages that may have come without it, but that's a bit unlikely... Damn.

Undertray

The undertray is allowed to be removed per 16.1.P, but is that going to hurt our aero and/or cooling?

The goal is to get the undertray as flat as possible, so measure where we can make the splitter back to, and after that see if the undertray is useful at all.

It's possible we can use the unrestricted drivetrain to make a flat cover over the driveshaft/exhaust tube to make the underside flatter. Explore this more...

Headlights

Stock headlights are quite heavy, and allowed to be replaced with a static setup. What options are there?

• Stock setup is 19.1 lbs (for EVERYTHING) from this post.
• This ghetto kit claims 25 lbs loss. Right...
• This bihalogen projector weighs 2.5 lbs in the box to fab something up
• They thought that this conversion might weigh less than the above projector but they're not sure.

Solo Rules

16.1.S. OE pop-up headlights may be replaced with static headlights, provided the replacement units are intended for automobile use on public roads as a primary means of illumination, and retain high and low beams as originally provided by the manufacturer. Minor repositioning of the headlights is allowed to accommodate the alternate headlight, but the unit may not be relocated and the repositioning may servce no other purpose. All associated hardware may be removed, replaced or modified.

Side Mirrors

How heavy are the stock side mirrors? We're allowed to replace them if we want...

Solo Rules

16.1.R. OE side mirrors may be replaced by aftermarket units, provided they mount in the same location, perform the same function as the OE mirrors, and have a reflective surface area greater than 15 sq. in.

Rear Fenders

The rear fenders are spot welded to the unibody, and as such may not be replaced with fiberglass pieces. As for flaring, SP's 15.2.A says, "Flares may be added although tires may extend beyond the bodywork", so we don't HAVE to put fender flares on the rear after we cut them down for clearance.

Fender Liners

They can be completely removed. 16.1.I says "Non-metallic fender liners may be modified, replaced, or removed."

Fiberglass Parts

This guy makes a bunch of fiberglass replacement parts, outlined below (emailed)...

Front Bumper/Fenders

How much does the stock stuff weigh? This site says 6 lbs/fender, and 10 lbs for the front bumper.

• Fiberglass/Kevlar: $1250, 20 pounds -- Has integrated fender flares, so don't need to deal with those breaking off all the time...

AWR makes a flared fender kit, but it weighs about the same as stock. The full kit is 1000$, but comes with rear flares that could prolly be sold.

It seems to just make sense to get the full FB/kevlar front end that guy makes. One integrated kit that comes with part of an airdam installed, with widebody fenders.

Rear Finish Panel

Sketchy if this is included in the 16.1.I language or not, but the stock piece weighs 3 lbs and aftermarket pieces weigh half that.

Hood

• Stock: 17.5 pounds
• CF/Glass: 750$, 11 pounds
• Full CF Honeycomb: 1950$, 4.5 pounds

I read something about vented hoods providing noticeable downforce. Would be worth exploring...

Wiper System

We can pull the wiper nozzles from the hood, but we have to keep the entire rest of the system (16.1.A and 16.1.I) so it's probably not worth bothering.

Rear Bumper

• Fiberglass/Kevlar: 600$

Aerodynamics

Solo Rules

Wing + Canards is a maximum of 8 sq ft. Front splitter can extend no more than 6 inches in front of the car.

Front Splitter

Not sure what to do with this yet. APR sells pretty generic flat splitter pieces here. Still need to come up with a way to mount it to the car, and to make an airdam for it. This guy makes a couple airdam options that might save some time.

Canards

APR sells generic canards here.

Rear Wing

Don Nimi has a guy that is working on a new twin element wing to the limit of the SSM rules. It'll be about 2k$ and hopefully ready by early spring.

Ciro Designs makes a bunch of wing designs here, but the SSM wing is only 5.7 sq ft. Ciro just released specs on their new wing design. It will have a 9.5" chord, and be up to 71" long, available in twin element configuration, custom built to customer spec. It will begin shipping in 5 weeks (around XMas). I've asked for the CFD data. It looks like the elements will be around 1k each, so the whole wing will be upwards of 2k$.

Wheels/Tires

Tires are required to be DOT, so we're stuck with the standard stock/SP tires (Hoosier A6, Kumho V/W710, Goodyear Eagle RS, etc.)

Miata.net has a nice tire size calculator.

Drys

I have a set of 15x10 custom Spinwerks wheels, with brand new 275/35/15 Hoosier A6s on them. The wheels are 13.2-13.4 lbs each. The tires have a 23.0" diameter.

Wets

What should we do for wets? The W710 comes in sizes that pretty much screw us. The old Hoosier Wet comes in probably 225 at widest for us (unless we can fit the 245/45/16). The new Hoosier Wet H20 comes in pretty identical sizes to the old one. 245/40/17 probably won't fit under the fenders, but we can investigate.

The only viable setup in the front seems to be the 225/45/15 Hoosier Wet H20. They suggest a 7-8.5" rim, so we should probably just get 15x8 6ULs. Need to do more research on if we can fit something bigger under the rear. It would make sense to run a staggered setup if we can fit something bigger back there...

Fuel Cell

The rules allow replacing the fuel tank with a fuel cell. How much does the stock tank weigh, and how much would an equivalent allowed fuel cell weigh? Keep in mind this is all weight that's low and pretty rearward, so it might not be the greatest idea to pull weight out of this area unless we just need to get down to weight...

Solo Rules

16.1.D.3.d has some detailed stuff:

d. The fuel tank may be modified or replaced. If the fuel tank is modified or replaced, the following restrictions apply:

1. No part of the fuel tank or fuel cell shall be closer than 6 inches to the ground unless enclosed within the bodywork and mounted above the floor pan. A metal bulkhead is required that provides total separation between the driver compartment and the compartment containing the fuel tank and/or filler/neck. This includes fuel tanks that are flush mounted with driver compartment panels or otherwise exposed to the driver compartment. Fuel filler doors in the driver compartment must be positively fastened (non-metallic fasteners are not allowed).
   For the purposes of these rules, a fuel tank consisting of a structure containing a fuel bladder is considered to be the entire fuel cell, including the containing structure. The containing structure of a fuel cell does not qualify as a bulkhead. A separate metal bulkhead must isolate the fuel cell from the passenger compartment.
2. Internal body panels may be modified to accommodate the installation of the fuel tank as long as such modifications serve no other purpose. In the event installation includes encroachment into the driver’s compartment, a metal bulkhead shall prevent exposure of the driver to the fuel tank.
3. Fuel tank breathers shall not vent into the driver/passenger compartment.
4. Minimum capacity of a non-standard fuel tank/cell shall be no less than five (5) gallons.

Other Lightening Ideas

Anything else we haven't thought of?

Troll the Lightweight Miata Forum for more ideas...?