Exterior
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Contents
Tow Hooks
Not allowed to remove the tow hooks.
Undertray
The undertray is allowed to be removed per 16.1.P, but we should probably keep it for Aero and cooling...
Headlights
Created a custom setup using the Morimoto Mini H1 bi-projectors and some normal halogen H1 bulbs. The full setup is 0.8 lbs per side. Currently using a Morimoto relay harness which is another 0.6 lbs of wiring, but can probably convert each side to just use some diodes on the stock setup if I care to, down the road. So, currently 2.2 lbs total for the setup including wiring.
Stock headlights are quite heavy, and allowed to be replaced with a static setup. I measured the stock stuff to be 19.2 lbs total (motor, projector, plastic and metal covers, and brackets).
- One guy says the 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... Axis Power makes replacements.
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."
Fenders
I got custom CF fenders from Axis Power Racing, which ended up being about 1.8 lbs each before I chopped them up to fit the tires. Stock fenders are 6.5 lbs each.
Front Bumper
The stock full bumper cover is 12.5 lbs. Need to figure out if a lighter FG alternative is possible.
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.
Rear Bumper
How much does the stock thing weigh?
Hood
I got a custom CF hood with 4 hood pins from Axis Power Racing. It weighs 4.7 lbs, and I made some tiny aluminum brackets for the rear and used 1/2" longacre aluminum hood pins to mount all 4 corners.
Stock weights (measured by me):
- Hood: 16.0 lbs
- Hinges: 1.4 lbs total
- Lock Assembly: ?
Venting
We need to figure out venting at some point. We can either go with simple NACA ducts on the back portion or do some real research to figure out where the pressure zones are. May want to incorporate an intake for the SC in there somewhere...
Wiper System
We can pull the wiper nozzles from the hood if/when we replace it, but we have to keep the entire rest of the system (16.1.A and 16.1.I). There's a proposal out for comment to allow removing the rest of the system too (would be really nice...)
JTEnt Fiberglass Guy
This guy makes a bunch of fiberglass replacement parts, outlined below (emailed)...
- Fiberglass/Kevlar Front End: $1250, 20 pounds -- Has integrated fender flares, so don't need to deal with those breaking off all the time...
- AWR makes a flared fender kit, but it weighs about the same as stock. The full kit is 1000$, but comes with rear flares that could prolly be sold.
- CF/Glass Hood: 750$, 11 pounds
- Full CF Honeycomb Hood: 1950$, 4.5 pounds
- Fiberglass/Kevlar Rear Bumper: 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.
Might consider trying Alumalite, at least at the start. Much cheaper and almost as light and rigid as CF honeycomb.
These guys sell Alumalite sheets - 119$ + shipping per 4x8 sheet.
Canards
APR sells generic canards here.
Miata specific 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. We'll need dual 9.5" elements, leading to around 1600$ total cost, but it won't be available until at least mid April.
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
I've bought 15x9 6ULs from 949 and some 225/45/15 Hoosier Wet H20s for now. In the future, we should experiment with the 245/45/16 to see if it will fit in the rear or even in the front, as that'd be a nice improvement over the 225s.
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.
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:
- 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.- 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.
- Fuel tank breathers shall not vent into the driver/passenger compartment.
- 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...?
