4WD MODIFICATIONS - POWERTRAIN
In extreme-modification situations it’s often advisable to re-ratio final drive gearing. However, this degree of modification needs to be carried out with great care.
Drive or gear ratios play a crucial role in determining how a vehicle’s engine power is transferred to the wheels. When larger wheels and tyres are fitted to a vehicle, the increased rolling radius of the larger tyres alters the overall drive ratio.
A change of final drive ratio can restore optimum engine speed and acceleration, but it’s not just as simple as that. Larger tyre radius also drastically affects braking power, because the standard brake power is designed to work though a given rolling radius. Increase that radius and you’ll definitely need upgraded brakes.
So, before you embark on a change of final drive ratios, you need to consult an engineer who specialises in approving vehicle modifications.
If your project passes the engineering test, it’s time to look for a gear supplier. In some cases, a suitable ratio set is available from the vehicle OEM, but in most cases you need to search for an after-market supplier. One such specialist company is Nitro Gear.
Nitro Gear and Axle is a premium USA manufacturer of high quality gear and axle products that have been precision engineered to suit customised four wheel drives and some other vehicles, including those with Ford nine-inch diffs. Nitro Gear also supplies Torsen LSDs for a wide range of vehicles.
Nitro gears are precision manufactured from 8620 Steel Gear Forgings that are Rockwell tested for hardness, triple lapped for smoothness and precisely machined, employing a five-cut process. The advantage of this process is that material is removed in a slower, more efficient and accurate method, resulting in gear sets that are arguably the quietest on the market with a set-up that is said to be significantly easier and less time consuming during fitment.
Ease of installation is a claimed standout feature of all Nitro Gear kits that come with all necessary parts. After the existing gear set is measured and the new Nitro gears are set up to that spec, more times than not, it will set up perfectly straight out of the box, the makers claim.
Roadsafe is Australia’s exclusive distributor of Nitro Gear and Axle products and product stock level inventory is based on local workshop demand. For more information contact Nitro Gear and Axle – 03 8878 1868 or www.nitro-gear.com.au