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Rally Car Prep

You have decided to take the plunge and transform your car into a rally car. Here are a few pointers to help you in the process on a budget. Most of the information is based on our experience with our Subaru RS, WRX & STI mostly GC & GD chassis (check the PrincesSTIFrogSTIrLe Toad and Le Toad 2 pages).
First thing is to check the rule books of the series you want to run with:

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.
You can try to do the cage yourself if you have a bender, tube notcher and appropriate welder and skills. It is usually cheaper, faster and safer to let a professional do the work, there is still plenty to do on the car besides the cage. The cost of a cage will vary depending on the complexity of the cage and how much stripping of the car you did (prices range from ~1000$ to 6k+$). Don't expect to go with a cheap bolt on cage, you need a welded in cage. Seam welding the chassis could also be a good option.
The cheapest option is to entirely strip the car yourself (remove all the interior parts, dashboard, wiring, etc... anything that is in the way of building the cage) which also sometimes require removing the front windshield and/or the roof of the car.
Come up with a detailed plan of what you want for a rollcage, provide pictures from existing builds and a copy of the rules to your builder to show exactly what you want. 

Once you have come up with a design, consult with the scrutineer who is going to issue the logbook to make sure he is ok with the design. Keep him updated during the build process too so that he can spot any issue before it is too late to fix them.

We have been using Bob Fill (http://bfrchassis.com) to build our cages with great success at a very competitive price.
You can also check the North America Rally Cage Builder Map: https://www.google.com/maps/d/viewer?mid=zP97LPvuElJ4.k55vLkhn6mps&hl=en_US

Car preparation

Engine:
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:
  • 34mm turbo restrictor ($225, http://parts.allwheelsdriven.net/index.php?main_page=product_info&cPath=1&products_id=48, also check Paul Eklund at Primitive Racing or Vincent Aze Trudel at http://www.performanceaze2.com/): if you use the stock ECU there are 2 things to be aware of: there is a risk of overspinning the turbo to try to make boost over 5500rpms, leading to a shortened life span for the turbo. Issue 2, running rich will dilute the oil, leading to main bearing issues, which is already a weak point in the motor, so you need to change your oil more often.
    The restrictor just sits in front of the turbo inlet and will be checked at tech with an inspection camera and a gauge for proper size and fitment.

34mm restrictor dyno tune



Exhaust noise can be an issue: Too loud and you could not pass tech, too quiet and you won't hear the engine during the race which makes it hard to know if you are in the right gear. Most stock exhausts will be too quiet but you can find cheap catback exhausts (you usually still need to run a catalytic converter) on eBay:

Drivetrain:
  • 4 pot/2 pot brake setup: ($1k used on eBay with rotors and pads, also great deals with Wali at https://jdmracingmotors.com/en/) to fit 15" gravel wheels, you can also buy new from KNS Brakes (http://www.knsbrakes.com/c/caliper-items/2344)
  • 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. We have successfully build scrapers from scraps of UHMW-PE plastic that we use for our underbody protection. You can just cut out a piece and use a sheet screw to attach it to the dust shield:

We also recommend upgrading to ARP long studs (https://www.amazon.com/gp/product/B001O065FY) with long open nuts (https://www.amazon.com/gp/product/B004QHMS5S).

Start with a cheap suspension like the KYB/King Springs and then upgrade to DMS or better when your budget allows. Most of the entry level suspensions are marginally better than the KYB setup. Buying used higher end suspensions can often be a great deal, just keep in mind the cost of rebuilds and who can service them so that you don't get stuck with unserviceable suspension. 

DMS suspension install and setup


We also recommend using socks/covers to protect the coilovers from dirt/sand/water that can produce corrosion or damage seals. Outerwears has good quality products in different sizes, with easy on/off using velcros (for DMS shocks use https://www.amazon.com/gp/product/B003TPYUQI, they come in pair so you will need 2 to cover the 4 shocks).





  • 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 plastic sheets of 2x4ft (0.125in thick) that you can get on eBay from 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!



Interior:
Make sure the seatbelt attachment points are going to give the right angles to the belts. Most comprehensive installation guide is here: http://www.schroth.com/installation-instructions/en/03_anchorage_locations_and_geometries.htm

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:
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!).
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. 

Exterior:

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)

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:
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!

Rally car safety equipment install and toolbox content

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. 

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:

Service crew training video


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:
  • Firesuit ($200): get a 3.2/5 Nomex suit, look at LeMons racing package deals, garage sales at SpeedWay Motors and even used ones on RacingJunk or eBay.
  • Helmet ($200): SA 2015 Helmet, try it before you buy it if you can as comfort is key. Comm integration can be a plus but usually comes at a high premium. Open face helmets are usually preferred for rallying.
  • Head & Neck restraint ($400): Hans device is one of the most popular, lots of debate on which one offers best side protection, but the bottom line is that only the halo on the seat is going to protect you in case of a side impact. 
  • Shoes ($100): Fireproof racing shoes are a must have for the driver and a good protection for the co-driver too. 
  • Gloves: Fireproof gloves will give you a much better steering feel for the driver, might not be great for the codriver to turn pages of the pace notes. We like our AlpineStar Tech 1 ($80, http://www.speedwaymotors.com/Alpinestars-3551614-Tech-1-Start-Driving-Gloves,83519.html)
Intercom:
You can go with the very expensive Peltor or Stilo intercom that are widely used or go on a budget with a motorcycle intercom like this one that we have been using successfully:
We recently switched to a 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.


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 attached at the bottom of the page to calculate the right angles for your car (https://docs.google.com/viewer?a=v&pid=sites&srcid=ZGVmYXVsdGRvbWFpbnxsZWZyb2dyYWNpbmd8Z3g6NmQyZWIyOWI5NzFiNGQxNQ)

Rally pacenotes explained



Rally computer:
We have had great success with a very simple Android tablet and some apps for both car telemetry and rally computer.
Android apps available from the Google Play store:
Video and telemetry:
Check out our dedicated pages:  Telemetry and Videos
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Emmanuel Cecchet,
Feb 6, 2016, 5:53 AM
Ċ
Emmanuel Cecchet,
Jan 8, 2017, 8:55 PM
Ċ
Emmanuel Cecchet,
Feb 5, 2016, 3:54 PM