Sydney Off Road Racing Association
Patron Ian Irons
NSW's Premier Offroad Racing Club!
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Sydney Off Road Racing Association NSW's Premier Offroad Racing Club!
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There are some great examples of low-buck club/state level cars in the SORRA club, just wander along to the next race meeting and ask questions. All drivers in the club are more than happy to talk about their racecars! Cheers,
Basic specs for Buggies This is based on our own R & G Offroad Racing class 2 car – but this info can be used for pretty much any buggy. We bought an old car and fixed it up, though others have bought complete cars ready to run or rolling chassis and dropped their own mechanicals into it. Assuming that any new comer would be like us and running to a pretty tight budget, here are the basics of a good club or medium state level buggy. Chassis: Like many cars out there, our car is 20 years old and still has plenty of life left in it. There are heaps of older chassis that will still run competitively. Some examples are Rivmastas, Hornets and Cobras. Plenty of older buggies are home made and perform well. All of these older chassis are based on VW suspension theories, even if they run all after market components. Front End Suspension: Based on VW symmetry a lot of older buggies run the following setup: Beams are VW King Pin front ends (pre ’64 are the strongest) that have had 2 VW front ends cut and welded together to make one front end 6" wider than standard. The original bearings are ripped out of the housing and replaced with one nolothane bush. Kombi torsion bars work well for a budget front end when paired with 4WD shocks such as Old Man Emu. A lot of cars still run beefed up Type 3 trailing arms, spindles and drum brakes. It’s a simple, cheap and reliable setup if its beefed up correctly. The next step up is to go to longer trailing arms, which means either after market torsion bars, or torsion bar adjusters need to be fitted. 2 inch over standard trailing arms work well for cars still using torsion bars. 4 Inch over standard front arms give a lot more travel and better handling, but coil over shocks will definitely be required. Ausshock, who’s information you can get from www.offroadracing.com.au, make excellent locally made offroad shocks. When it comes to link pins 22mm jobs are the go. We use Wright Bros (American) king pins in our car, though there are Australian manufacturers making them as well. When it comes to hubs & spindles there are plenty of Aussie engineering companies making good aluminium stuff including Trik who advertise on the main offroad site. The ducks nuts when it comes trailing arm setups is a chrome moly torsion bar housing with 4 inch arms and 2 coil overs per side. (Note that we have installed this type of front end in our car in 2003 and it made a huge difference in handling). Rear Suspension: Again, most cars still use the basic VW suspension theories. For a budget club car type 3 trailing arms brakes and hubs will work but aren’t seen around very often. The don’t really have the travel required for the heavy end of the car and require a very stiff setup to stop it from bottoming out over jumps. A lot of cars run trailing arms that are from 3 to 6 inches longer and wider than standard. We run 3x3 over rear arms (3" wider, 3" longer) and it works great. A good budget conscious rear end is to use type 3 or Kombi torsion bars and another set mounted up a bit higher that only come into effect after the suspension has travelled a set distance (progressive torsion bar setup). Another option is to run aftermarket (sway-away or similar) torsion bars, and yet another is to run 1 coil over shock working in tandem with a type 3 or Kombi torsion bar. Talk to everyone to find out what they like before committing yourself to a setup! Long shocks (10 to 14 inches of travel) are pretty much essential in the rear, though 4WD shocks could still be used for club racing. Ausshocks are a good option if you can get them second hand as you can strip and rebuild them yourself. Rebuild kits including seals, valving, heim joints etc are available across Australia. Advice on valving, spring rates etc is also readily available. A mate in Kempsey has just modified an existing set of non coil over 10" Bilstein shocks to enable him to put coils over them as a cheaper but effective option to run more spring in the rear, and still allow it to be adjustable. If the quality of this type of coil over is good enough there is no reason why this shouldn't be an effective way of setting up the car. Again, there are plenty of Aussie companies making aluminium rear hubs, different sized rear arms etc so again, ask around. We run a cut down Kombi drum brake with a valiant disc rotor mated to it for our hub/brake setup. It’s a bit heavy but its cheap and wont let you down. Brakes: VW stuff is always available and is cheap and reasonably reliable. The downside is the unsprung weight and braking power. If you’re thinking of running aftermarket discs on the front then motorbike calipers are the way to go. It sounds strange but with very little weight on the front of the car they work very well. We use twin spot Suzuki calipers off a 900cc bike. Alot of people run Camira or S1/S2 Bluebird front calipers on the rear of the racecar. Again, they're cheap and reasonably light, and provide reasonable stopping power. After market brakes with more stopping power could of course be used. Most buggies run steering brakes giving the driver the ability to brake one rear wheel at a time. When applied with a bit of throttle the car will turn quickly, though it could take some getting used to. Use them too heavily and all of a sudden you’re too far sideways and losing forward momentum. Use them too early and your gonna find yourself cutting a fire trail! Brilliant fun when you get it right though! CNC make a good turning brake setup – we went for two separate PBR master cylinders working off 2 levers for a cheaper way of doing it. Most cars don’t run brake boosters, but rather larger bore master cylinders to stop erratic braking pressures due to changes in vacuum. Steering: Aftermarket rack and pinions are the way to go. They are simple and designed to take the punishment that offroading can deliver. Some cars run Chevy type racks, but I have no experience with them so can’t comment. Power steering systems are many and varied – we run an aftermarket UMP ram, a modified VB Commodore actuator valve and an old RB Skyline pump. Reasonably cheap and if the power steering blows a line you can still steer yourself out of trouble! Some cars run forklift type power steering but it puts a huge load on the pinion, but hey, a lot of quick cars do it that way so it must work. Of course a lot of guys don’t run power steering at all. By changing the angle of the beams on the front of the car to a more vertical position you get lighter steering – the downside is the handling isn’t as good and the car can skate quite a bit at high speed with the reduced caster. Again, ask around. The last alternative – go to the gym and start working out!!! (yeah - bugger that!) Wheels: For a budget buggy steel rims are the way to go. Brand new they cost between $80 to $120. Heaps of guys still run steel rims and are competitive. Most buggies run 15" rims both front and rear, 4" or 5" width on the front, anywhere from 8" to 10" on the rear. Of course there are heaps of steel rims lying in garages, so if you're after a set of spares drop a wanted ad onto the classifieds page. Aluminium rims are available. We use aluminium 2 piece rims, 15" x 4.5" on the front with double rolled lips for added strength and 15" x 10" on the rear with bead lockers on the outside of the rim to stop from peeling tyres off when running with low tyre pressures, and so you can still drive yourself back to the pits if you spike a tyre. They aren't cheap though, but they certainly have their advantages. One is that they are stronger and lighter than steel, and they can be reshaped if you have a really big hit. With the front tyres alot of guys run grooved Yokohama's about 28" tall. Big enough not to fall into to many holes and to walk over obstacles, small enough to have good response and feel behind the wheel. The extra grooving also gives them good bite. Ian Boyd from Hills District Tyres can sort these out for you, including the grooving. Hancook 28's are also popular, though the tread pattern is suited more towards sandy surfaces and not really suited to wet, muddy tracks. We run 31" tall tyres on the rear so that we get reasonably good clearance and it doesn't bog the engine down too much. We ran Hancooks on the rear last year as the tread pattern is not too aggressive, again so that we weren't robbed of horsepower when racing. Bridgestone and BF Goodrich mud tyres are very popular due to their wearability and traction, though you'll pay extra bucks for these compared to the some other tyres. Basically, if you have tyres that keep your car off the ground then use them! Everyone runs commercially available 4WD tyres, not specific motorsport tyres like rally tyres due to their durability and price. Transaxle/gearbox Basically for a club/state car you have one option. VW. Be it 1800 Kombi, 2ltr Kombi even 1600 Kombi there are plenty of offroad components to be bolted in. The gearbox is probably the weakest link in the car as it takes heaps of punishment. Don’t be tempted to run a standard gearbox – it will not last (Im talking from experience!) and the gear ratios are abysmal. 1800 Kombi is the way to go as it gives you the best diff ratio, but many parts are interchangeable. The options for a club car gearbox are many and varied – we run shortend aftermarket gears, super diff and extra spider gears in the diff and it got us through a majority of the 2002 state championship. You can go further than this – it depends on your budget but consider the above as a minimum. The CV’s are also recognised as a weak link. Kombi CV’s can be used successfully if you don’t have huge amounts of travel in the rear, but almost everyone runs Porsche CVs. We actually run 7 series BMW CVs as they are the same size, shape and are almost as good as the Porsche ones at a cheaper price. We’ve had no problems with ours at all. A little bit of linishing and some specialised offroad cages and you’re on your way. Axles are all aftermarket items as if you put in longer trailing arms, so must you put in longer axles. We picked up ours second hand and they’ve worked a treat. Engine: There isnt enough space on this site to put in everything about engines so Ill run through the basics: Class 1 or 9 – a lot of guys run Nissan SR20DETs, Honda B series VTEC turbos and Toyota 4AGZE (either supercharged or turboed) engines. In class 2 it’s the Toyota 4AGE 86kw, 100kw or 20 valve engines that are the pick though there are a few Subaru, Mitsubishi and Daihatsu engines getting about. Suzuki 1300 GTI's are definately the pick for class 3. Heaps of guys will buy an engine from an importer and give it a quick rebuild, rings bearings etc and bolt it in the car. A programable computer is pretty much essential to produce decent power, especially using a stock rebuilt engine. EMS is pretty well proven in offroad, though not as flexible as Motec. When it comes to club racing you cant beat a Datsun engine (though I may be biased!) 2ltr for class 1 and 9, 1600 for class 2, 1200 for class 3. Even though they are absolutely bulletproof you don’t see many around any more as import engines are pretty cheap, but if you’ve already got one – don’t wait! Go racing!!! (Note that we're now in the process of dropping in a 16V 4AGE so Ill eat my words on the previous paragraph!) We got 3rd in class the 2002 NSW Championship with a Datsun 1600 and a single 45DCOE weber, so there cant be too much wrong with them, though we’re gonna get excited and fuel inject it pretty soon! (err... we never did get around to that! we dropped in the import engine instead!) Waffle: That’s pretty much the basics for a cheap runner. Our car is not as advanced as some of the others but we certainly did well in our rookie season. The biggest advantage for us in offroad is that there are 2 people in the car, and to some extent you can share the driving – and therefore the costs. We basically go away for one weekend a month for camping, barbies and beers. And to top off what would already be a good weekend we get to go screaming through the bush launching cars of jumps! The best advice I can offer anyone is to go to race meetings and talk to the people. Go to club meetings and get involved helping out the officials and organisers if you’re still working on getting a car running. The biggest asset offroad has is its people. Everyone and anyone you meet will be prepared to have a yarn, to answer a question or to give advice. Even your closest competitors which is a rare thing in motorsport. The next best bit of advice I can offer is that beer slabs are the offroaders most useful commodity! We’ve had heaps of bits machined, made, modified, borrowed etc and all for a case if beer here, a case of beer there. Jump onto the calender to find out when the next event is on, or if you cant find what you’re looking for then feel free to drop me an email to the address garry.myers@offroadracing.com.au.
Cheers, |
