Building a Rally Car

New vs older cars

Older chassis do not have the same rigidity as newer chassis that use more elaborate materials such as high tensile strength steel and have crush structures designed to absorb larger amounts of  energy.  In the pictures below taken around 1994/1995 in Rally Australia, you can see a Subaru Group N spec car, built by STi, seam welded shell, welded in cage, no sill bar. It was ‘just a roll’ but the bottom slammed a tree of only about 6-8 inches wide, the bottom of the car hitting first mid roll. Occupants survived but hurt necks. (Thanks to Jeff Denmeade for pictures and information about this incident).

Consider that you might have to plan for more safety improvements on older cars..

Rollcage building

This is a major undertaking and will require careful attention to get it right. First step is to check the rule book, but basically if you follow the FIA rules you will pass with any organization.

Check our dedicated Rollcage page

Car preparation/build

Engine, turbo restrictors, air intake, fuel lines:

Check our Engine prep page

If you are new to the sport, you don't need to go crazy and a stock engine will most likely be the more reliable option. Eventually get a mild tune but more importantly stay on top of the maintenance schedule and replace fluids and all wear parts in time. If you have a turbo car, you will most likely require a restrictor: Read all the details in the Engine prep section

Brakes: 

Since most gravel tires are only available in 15", stock STi Brembos have to be replaced with smaller brakes. The go to setup is a 06/07 USDM WRX 4 pot front, 2 pot rear caliper setup and matching rotors. Note that if you have an STi, the rear brake drum for the ebrake is bigger and you'll need special rear rotors (see below).

• • 4 pot/2 pot brake setup: ($1k used on eBay with rotors and pads, also check JDM imports) to fit 15" gravel wheels. Not as pretty but every bit as functional are reman calipers (~$60 a piece Front: https://www.amazon.com/gp/product/B082MKSNSY / Rear: https://www.amazon.com/gp/product/B0839FBJWY). Hardware kits: Front: Centric 117.47021 / Rear: Dynamic Friction 34013019.

  • Rotors: Using a high carbon alloy, especially in the front can help dissipate more heat. You can use the KNS rotor up front (https://bleedingtarmac.com/products/kns-brakes-front-rotor-02-14-subaru-wrx) that is significantly cheaper than a DBA T3 but for the rear you'll need a size that matches your ebrake drum, for the STi we recommend the KNS rear gravel rotor (https://bleedingtarmac.com/collections/brakes/products/kns-brakes-dual-drilled-2-pot-rear-gravel-rotor-04-07-subaru-wrx-sti).  Also check out Frozen Rotors at Rally.build: https://rally.build/collections/frozen-rotors

  • Brake pads: the Hawk HP+ is a pad that offer fantastic cold bite but can be reach its heat limit on heavier car on faster events that require heavy braking. If you are a heavy left foot braker, you might want to consider a more aggressive compound like the DTC-60. We usually use the HP+ in winter and the DTC-60 on faster and grippier events from fall to spring (note DTC-60 only in the front, we keep the HP+ in the back all year around).

  • Consider making wheel scrapers especially for the rear calipers as the clearance between the rim and the caliper will cause sand/gravel to grind down the caliper and make it fail prematurely (see picture on the right below) . We have successfully build scrapers using a metal bracket directly attached to the caliper. Video of how to make wheel scrapers below:

Don't overthink your suspension setup, more caster is better if it's adjustable. 0 toe front/rear makes the car very neutral (on AWD). Don't put too much camber, the tires don't have racing slicks level of grip on gravel. Swaybars is a matter of preference, we just run stock sway bars on our cars and the balance is great with stability at higher speeds. You might find a little bit more grip without sway bars especially on lighter cars but it will be a tradeoff for stability at higher speeds. Experiment and see what works best for you. Below is a cheat sheet from Whiteline to adjust your understeer/oversteer balance:

Strut tower reinforcement 

To prevent struts tower to mushroom or even complete tear off, weld-on strut reinforcements are a must ($30): http://rally.build/subaru-impreza-gd-weld-on-strut-top-reinforcement/

 Skids plates

Primitive full rally armor skid plates front and back to protect  the engine and drivetrain in the most rugged conditions. (check http://get-primitive.com/3-protection-skidplates)

Underbody protection 

The underbody protection protects other portions of the underbody like the gas tank from rock projections and other road debris. We have successfully used UHMW-PE sheets of 2x4ft (0.125in thick) that you can get on Zoro tools with free shipping. You will need 3 sheets to do one car. In our first iteration we tried to secure the pieces with the strongest zip ties we could find but they get ripped  under impact, the only way to go is to weld either nuts or bolts to hold your pieces of underbody protection. Using zip ties in the rear on moving lateral links is fine. Write your name on the pieces in case you lose them, sweep might bring them back to you if they know who they belong to!

Rear subframe reinforcement

The rear subframe on the STi GD chassis is prone to cracking with the loads applied on the rear axle. To prevent the cracking, welding a reinforcement plate to limit the flex around the holes for the diff carrier bolts can go a long way. See the video below:

Fender liners 

Stock fender liner replacements can be found for cheap (~$20: https://www.amazon.com/gp/product/B004GD40GM) but  in case it gets ripped off the car, it exposes the engine wiring harness to road debris. A simple protection using UHMW-PE (same material used for underbody protection above) can protect your wiring harness. See the video below:

Hydraulic ebrake

Requires replumbing the brake system and using an aftermarket DCCD controller if you don't have a mechanical center diff. There is a detailed thread on the Facebook Rally page at https://www.facebook.com/groups/1649355358677665/permalink/1663650153914852/?comment_tracking=%7B%22tn%22%3A%22O%22%7D

The stock ebrake will be fine in most situations, just remove the spring and replace the button with one that has a lip (oftentimes called drift button). See video below for the install:

Interior

Most of the time, the stock rearview mirror is usually enough, however the vision can be limited on the street with the cage and halo seats which can be an issue in transit or if you use the car for other activities like wheel to wheel racing. You can use a cheap clamp-on panoramic mirror that is very easy to install but add weight to the original mirror mount which might not stay in position during the stages.The rollcage mounted mirrors are more stable but can be tricky to install depending on your roof bars configuration and they will instantly break if they are hit by a helmet (which can happen if you get in/out in a hurry). After breaking multiple rollcage mounted mirrors (and it's a mess to clean the broken glass), I am happier with my clamp-on mirror, never broke one and very reliable on the street (don't really need it on stage anyway!).

• • Clamp-on 17" rearview mirror: http://www.amazon.com/gp/product/B000GKAZMW (We do not recommend this option anymore, it becomes a flying object in case of an impact)

  • Rollcage attached mirror: http://www.amazon.com/gp/product/B001NN7AOM (Will break if you hit it with a helmet, be careful getting in/out of the car!)

For night stages, interior lights are necessary. While you can get by with a flashlight, the navigator needs a good light to read the notes, find the time card and so on. 

Rollcage padding

• •  (~$20 for 3ft, plan on 15 ft for a good coverage): SFI rated mini-padding where the helmet can reach the bars (http://www.jegs.com/i/Allstar+Performance/049/ALL14112/10002/-1), high density padding for door bars, winshield bar and bottom of a-pillar reinforcement bar (http://www.jegs.com/i/Longacre+Racing/441/65162/10002/-1). You might find cheaper padding from Pegasus (https://www.pegasusautoracing.com/productselection.asp?Product=2395)

Door cards

 We recommend keeping the stock door card and only doing minimal cuts to clear the cage. First the stock door cards don't weigh much and there are not much weight savings to be made there. Second you won't have to relocate door locks or window controls. Third it will provide padding for your elbows and extra storage at the bottom for a tire gauge, paper tower, etc...

Seats

Bimarco Phantom (less than $500+shipping each directly from the manufacturer. The seats have to fit you well, make sure you try them before you buy them, there is a lot of difference in terms of size and fit from different brands and models. Check our Seat installation page for more details.

Seat mounts: Consider having your cage builder weld square tubing for you seat mount. Alternatively you can use a Planted seat mount using the stock mounting points ($140 a side): driver (http://www.amazon.com/Driver-Bracket-Sparco-Recaro-Bride/dp/B0087OYCGO) and passenger (http://www.amazon.com/Passenger-Bracket-Sparco-Recaro-Bride/dp/B0087OYCZA). Check our Seat installation page for more details.

Steering wheel

Getting in and out of the car with the cage and racing seats can be very challenging, adding a removeable steering wheel will make your life much easier:

• • Sparco 383 steering wheel ($210): http://www.amazon.com/Sparco-015R383PSN-Suede-Steering-Wheel/dp/B000ECPZAY

  • NRG short hub SRK-100H ($80, https://www.amazon.com/NRG-SRK-100H-Steering-Adapter-Mitsubish/dp/B00HXLY5T6) 

  • NRG 2.5 quick release ($110, http://www.amazon.com/NRG-Steering-Wheel-Quick-Release/dp/B00HK1HX84)

Most regulations ask you to remove the steering column lock (also check kill switch install in the Safety equipment section below). Here is a howto:

Horn

Since installing the racing wheel removes the horn button on the steering wheel, we can wire a separate button or go for a wireless solution. If you need to install a horn without the need to run wires through the firewall, there is an option out there called the Big Bubba (https://www.boomblasters.com/product/big-bubba-programmable-4-sounds-wireless-car-horn). It comes with a 4 button wireless remote and allows you to upload up to 2MB of MP3s total (1 file per button). See the install video below: 

Roof scoop

Do yourself a favor and keep all the stock venting/blower/heater in the car, even AC if you can. Rally.Build has a nice Evo style roof scoop with vents to direct air where you need it (https://rally.build/collections/rally-build-fabricated-rally-parts/products/carbon-fiber-evo-style-roof-scoop?variant=6807567269934). If you go for a traditional roof scoop and vent like the one offered by Primitive Racing (https://get-primitive.com/exterior/5-rally-roof-scoopvent.html), it will only blow air below the vent but not on the sides. If you want air to get to the driver and codriver, get a floor vent from the hardware store and glue it to the bottom of the roof scoop vent as show on the picture below. You can also use additional safety wire to secure it in place if needed.

• • Classic map light ($50): http://rally.build/sparco-flexible-map-light/

  • Truck bed lighting kit available at Walmart ($19) as shown on pictures above: can also be used to illuminate rear compartment for spare or tools.

Exterior

Hood pins

Rally regulations and most road racing sanctioning bodies require the main hood latch to be disabled and hood pins to be installed. Note that hood pins are a wear item and you will have to change the studs over time as they will wear out with the constant opening/closing of the hood at every rally service.

A note that we don't use Aerocatch style hood pins as they do not work in cold weather where ice buildup makes them impossible to open. Also in case of an impact the Aerocatch latch mechanism breaks and makes it impossible to open the hood (but they look nicer for sure!). 

The hood pins used in the video below are the generic inexpensive kit found on Amazon at: https://www.amazon.com/gp/product/B08L8TPFYY

Hood struts 

($65): Tein hood struts (https://www.ebay.com/itm/NEW-Bonnet-Hood-Lift-Gas-Strut-Shock-Damper-Kit-Impresa-STi-WRx-GDB-GD-GG-GGA/273038708236)

Mud flaps

Rally Armor UR mud flaps ($135): http://www.amazon.com/Rally-Armor-UR-Mud-Flaps/dp/B004PBAF4Q

Decals 

Decals for driver/codriver names, kill switch, fire extinguisher ($20): http://rallygrafix.myshopify.com/collections/decals-rally-competition
The graphic packages with the windshield banner and door cards are specific to each series. Check their current provider for their visual package as it might change every season.

As Imprezas are pretty nose heavy, you can shave some weight by installing a lightweight bumper beam from Oswald Performance (https://www.oswaldperformance.com/products/gd-front-rear-beam-set?variant=1157639532)

Light bars / Light pods

Stages at night will be very challenging with just the stock headlight, adding a LED light bar has become a pretty inexpensive solution. Some of them can be mounted directly on the hood or roof of the car but a bumper or light bar is usually a better option:

• • Front bumper/light bar ($270): http://shop.rallyinnovations.com/collections/rally-light-bar is a good mounting option for light bars if you don't want to secure it directly to the hood

  • LED bar: Cheap light bars do work for starters http://www.amazon.com/gp/product/B00KQXKG46 ($37) and wiring harness with waterproof connectors (http://www.amazon.com/gp/product/B00QFSAPP6). If you want to wire the LED bar to work with your high beams, you will have to re-wire the relay (see attachment at bottom of page). When you start to pick up speed and need further down the road vision, upgrade to a Diode Dynamic Stage series bar, we are currently using the SS30 combo light (https://www.diodedynamics.com/stage-series-30-white-light-bar.html) attached at the end of the hood. Check the rules for light bar placement and avoid blocking openings for your radiator or cooling system.Old light pods look good but are very pricey and bulky, they also make it harder to operate the hood.

Check the document below if you want to wire your LED bar with your high beams (required if you are running under CARS rules). If you can't see the document, the direct link to access it is: https://drive.google.com/file/d/1q5f4InXo51GgUw4eoSUkR_jkbOEnMOeQ/view?usp=sharing 

Safety equipment

We are able to store most of the safety equipment in a toolbox that sits on top of the spare tire. The tie down keeps everything secure and in place. Make sure you don't get a cheap box that will be crushed as soon as you ratchet the strap and also make sure objects are secure in the box and are not flying around, causing damage to the box and eventually ending up flying in your trunk!

• • 3 safety triangles ($20): http://www.amazon.com/gp/product/B00AZ9PHDG

  • First aid kit and spill kit ($100): get it from Rally.Build (https://rally.build/collections/rally-build-fabricated-rally-parts/products/first-aid-spill-kit-combo)

  • Fire extinguisher: if you are on a budget the cheapest is $20, http://www.amazon.com/Kidde-FA110-Purpose-Extinguisher-1A10BC/dp/B00002ND64 but you should consider a metal-refillable one like the Amerex B417 (https://www.amazon.com/Amerex-2-5lb-Chemical-Extinguisher-Bracket/dp/B0089XA6Y0). The cheapest metal bracket is ~$10 (http://www.amazon.com/Kidde-420118-Mounting-Chemical-Extinguishers/dp/B00002NC0N) but if you go racing in Canada you'll be required a double strap with torpedo tabs bracket like this one (https://www.zoro.com/amerex-fire-extinguisher-bracket-vehiclemarineaviation-bracket-steel-for-tank-weight-25-lb-817s/i/G4154394/). Note that you can find the Amerex product for much cheaper on eBay or through Zoro tools.
    Anti-torpedo tabs prevent the fire extinguisher from sliding through the straps. Watch the incident at Tall Pines 2014 that triggered this rules (jump at the 16:45 mark in the video below):

• • Fire suppression system (~$400): Since June 2021, ARA requires a fire suppression system in addition of the 2x10BC handheld fire extinguishers.  Check our dedicated Fire suppression page for complete info. Cost is $400 for an AFFF based system with manual trigger and can go well over $1k for Novec systems with electric release.
    For a good deal on a Lifeline system, contact Matt Pullen on Facebook messenger, or at 403 708 0148 or Matt@m2motorsport.ca. Check the installation video below:

• • Kill switch: Required since 2019, this will disconnect the battery power and shut off the engine/fuel pump in case of an emergency. You need at least a 4-pole (2 poles for the battery, 2 poles to kill the engine) but can also run 6 poles (2 extra poles to drain power from alternator to prevent power spike). Wiring diagram and explanations on the dedicated kill switch page. Cost about $30 for a 4 post switch: (http://www.amazon.com/gp/product/B012UW1GAI). Also plan for firewall pass through connectors (https://www.amazon.com/Fastronix-Premium-Current-Terminal-Connectors/dp/B079K5HB79)

A better but more expensive option (~$300) is to use a Cartek GT solid state kill switch (https://rally.build/collections/rally-build-fabricated-rally-parts/products/cartek-gt-solid-state-battery-isolator-kit), much safer as you don't have to run high gauge wires through the car (see video below and check the  kill switch page):  

If you can't see the document above, the direct link is: https://drive.google.com/file/d/1q5f4InXo51GgUw4eoSUkR_jkbOEnMOeQ/view?usp=sharing 

• Jack 

  • • Use an impact gun adapter for the stock jack (https://www.amazon.com/gp/product/B0793PJBB6) but keep in mind that the stock jack is weak and will not withstand abuse with the impact

    • ($30): Low profile double ram bottle jack/stubby bottle jack (https://www.amazon.com/dp/B002RZC8WE/)

• • Spare tire tie down ($50): http://rally.build/sparco-spare-wheel-tie-down-strap/

  • Tow hook: the OEM tow hooks are usually fine, just make sure they are in place.

  • Tow strap ($12): http://www.harborfreight.com/2800-lb-capacity-2-in-x-20-ft-heavy-duty-tow-strap-61943.html 

  • Torque wrench ($11): http://www.harborfreight.com/1-2-half-inch-drive-click-type-torque-wrench-239.html

  • Stowable 4-way lug wrench ($10) : http://www.harborfreight.com/14-inch-stowable-four-way-lug-wrench-95932.html

  • Impact gun ($99): Ryobi One+ 1/2 inch impact is the cheapest impact that actually works (https://www.homedepot.com/p/RYOBI-18-Volt-ONE-Lithium-Ion-Cordless-3-Speed-1-2-in-Impact-Wrench-Kit-with-1-4-0-Ah-Battery-18-Volt-Charger-and-Bag-P1833/302648209)

  • Emergency tire inflator ($25): Ryobi P737 uses the same battery pack as the impact gun (https://www.homedepot.com/p/RYOBI-18-Volt-ONE-Cordless-Power-Inflator-Tool-Only-P737/206159256)

  • Emergency HAM radio ($30): Baofeng UV-5R+ https://www.amazon.com/dp/B0097252UK

If you can, try to get basic first responder training or training in fire extinguisher usage. In case of an accident on stage and the need to quickly extract a person from a car, check the useful FIA Safety Extraction Guide, especially the section about the quick modified Rautek maneuver. 

Spares

Inevitably things will break during rallies even with the best possible prep. It is necessary to carry spares with you so that the car can be fixed at service. Here is a list of spares we carry with us:

• • wheels/tires

  • brake rotors/pads/calipers

  • cv axles front/rear (complete and/or boots)

  • ball joints

  • swaybar end links

  • control arms/spindles/knuckles/trailing arms (4 corners)

  • suspension (4 corners)

  • driveshaft

  • differential

  • clutch/transmission (if multi-day rally)

  • radiator

  • hoses (vacuum, fuel line, brake lines...)

  • fuses/relays/light bulbs/electrical wire

  • sensors (MAF, camshaft, crankshat...)

  • coil packs

Check with Wali at https://jdmracingmotors.com/en/ for great deals on spare packages.

Of course you will also need all the tools necessary for service. Check our service crew training video below:

Car reprep between events

We have a checklist of things to check between events or during long/overnight service at rallies. This makes sure that all the critical points have been checked out. The list is this Google spreadsheet: https://docs.google.com/spreadsheets/d/1W_J6Qzcyn3-gM1T_rI3spfpWSrJIEidTGCO91UJIva8/edit?usp=sharing

For each event, we make a copy of the template in a new tab and we change to green every point that has been checked with possibly comments in the cell if some action has been taken or something has been observed (worn part, loose bolt, etc...)
There a rea also wear items that need regular servicing or replacement. Here are a few of our maintenance schedules:

• oil change: after every stage rally or track event, every other rallysprint or hillclimb (depending on number of runs)

• rear diff oil: twice a season

• transmission oil: once a season

• air filter: cleaning after every event, change as needed (usually not more than one season)

• suspension: full service once a season (see DMS page)

• lug nuts: every other season (might be earlier if excessive wear/rust)

• rust protection/underbody coating: once a season

• balljoints and outer tie rods: max 3 seasons, earlier if any play detected (regrease twice a season with sway bar endlinks if aftermarket serviceable ones are used)

Driver/Co-Driver equipment

Some safety equipment can be bought used (but it is sometimes hard to make sure that the equipment is safe and has not been involved in an incident). Some overseas companies like Demon Tweeks or Murray Motorsport have substantially lower prices on new equipment even with shipping and tax duties factored in. 

Safety gear

Check our Safety gear page for information about helmets, gloves, shoes, Hans devices, arm restraints, etc...

Intercom

You can go with the standard Peltor or Stilo intercom that are widely used or go on a budget with a motorcycle intercom:

• • Bluetooth motorycle intercom (~$100): https://www.amazon.com/dp/B00PKECGJ4

  • Motorcycle intercom ($50): http://www.amazon.com/gp/product/B0002IOI9Y

  • Color mic windscreens to differentiate easily driver/co-driver headset ($7): http://www.amazon.com/gp/product/B004H6PC4M

Budget intercom: Sparco IS110 amplifier (~$90) that has both a 9V battery power and 12V from the car for seamless power transition. You can get headsets for open or closed face helmets for about $45 a piece at http://www.demon-tweeks.co.uk/motorsport/intercom-headsets/sparco-headset-kit-for-is-110-intercom. The regular audio jacks are not very reliable and will fail quickly especially if you forget to disconnect them when getting out of the car. 

Higher end intercom: Sparco IS140 is a nice high end Peltor compatible intercom that has both a 9V battery power and 12V from the car for seamless power transition. It turns automatically on when the codriver connects his helmet. Stilo helmets will require a Stilo-Peltor cable, other helmets can use a comm kit like this one: http://www.rallynuts.com/helmet-headsets/rosso-racing-advanced-pro-open-face-headset.html 

Recce wheel

If you need to write your own pace notes, you will need to get consistent notation for the turns. Getting a used steering wheel and adding marks to it to indicate the angle of corners is a good practice used by WRC drivers (see video below).  Check the pdf document under the video below of the page to calculate the right angles for your car.

If you can't see the document above, access it directly here: https://drive.google.com/file/d/1M9kx3j6CpJr-H9Xh20U4XaXVf4B0ulUD/view?usp=sharing

RallySafe

Check our RallySafe page for installation video and instructions

ARA and select CARS events have switched to RallySafe for timing and tracking during events.  You can purchase the permanent kit from https://shop.statusas.com/shop/category/rallysafe/

Rally computer

We have had great success with a very simple Android tablet and some apps for both car telemetry and rally computer. Alternatively you can use a modern phone, what really matters is that you have a dual GPS/GLONASS receiver for accuracy. Note that the use of a rally computer is not really useful beyond recce when using RallySafe, since the RallySafe unit provides similar features to a rally computer.

• • RAM mounts to secure tablet to rollcage: 

    • rollcage tie ($17): http://www.amazon.com/gp/product/B0030HO6SM

    • tablet holder ($30): http://www.amazon.com/gp/product/B005MFKV20

    • ball mount for tablet holder ($7): http://www.amazon.com/gp/product/B004O8LF26

    • long arm ($18): http://www.amazon.com/gp/product/B000WJA5ZY

  • Bluetooth OBD2 for telemetry ($7): http://www.amazon.com/Version-Bluetooth-Multi-Language-12Kinds-Android/dp/B00N2K6M2A

Android apps available from the Google Play store:

• • Torque Pro to see live car data, reset Check Engine Light...: https://play.google.com/store/apps/details?id=org.prowl.torque

  • RaceChrono for timing and telemetry recording: https://play.google.com/store/apps/details?id=com.racechrono.app

  • Rally tripmeter for stage rally navigator to keep track of time and distances: https://play.google.com/store/apps/details?id=ee.siimplangi.rallytripmeter

Video and telemetry:

Check out our dedicated pages:  Telemetry and Videos