TECH TORQUE

RISKY BUSINESS

STORY AIDEN TAYLOR PHOTOS CHRIS THOROGOOD

> PACKING 2000HP, PETER GRMUSAíS ALL-CONQUERING XR FALCON SKID RIG, ATRISK, WAS A BIT OF A PIG TO DRIVE. NOT ANYMORE!

PETER Grmusaís ATRISK XR Falcon is hands-down one of the most insane burnout cars in the scene. The specs are out of this world: 700ci big-block Chev, giant blower and 2000hp. It has enough grunt to take a tyre from brand new to a pile of dust in a matter of seconds; youíve never seen a car so violent out on the burnout pad.

ATRISKís first incarnation won the Summernats Burnout Championship in 2006 and 2007 and was on the cover of the February 2008 issue of Street Machine. In 2013 Peter gave the car a break from competition so he could revamp it into its current form; in its place came the EVILXA Falcon ute, which won the Summernats 26 Burnout Masters. Overhaul complete, ATRISK was again an SM cover star in February 2014.

Away from Summernats, Pete has won just about everything there is to win in ATRISK; he reckons prize money would have to be in the six-figure range. Jeez! But now that competition within the burnout scene has gone mad, itís only getting harder to win comps, so itís time to step it up a notch.

Itíll be no surprise to anyone that an XR Falcon with 2000hp is a bit of a handful to drive, but Peter reckons it shouldnít be. ďWhen we built it we cut out the whole floor and put in solid rails, so itís actually really stiff; itís just a pig to drive because the front end was never designed for the kind of engine set-up I have,Ē he says.

ďItís actually a hot rod front end modified slightly with parts from here and there. The control arms started bending from the weight, so we welded in some reinforcement plates, but it never really solved the problem.Ē

STEP

ATRISK arrived at Castlemaine Rod Shop basically as a rolling shell, with the motor, trans and front body panels all removed to make the job as easy as possible for the boys.

First, the locations of the existing control arms and hub assemblies are measured, to ensure the new gear goes in exactly the same spot so that the tyres sit in the same place.

Then itís all removed and thrown in the bin

STEP

Sparks fly as the crossmember that the steering rack and control arms are mounted to is cut from the chassis rails.

It will be replaced by a much stronger and chunkier unit, made in-house from laser-cut steel. First the top control arm mounts are cut off, followed by the main beam connecting the passenger- and driverís-side chassis rails. The rails are then smoothed back to clean metal, ready to mount the new gear

STEP

The new crossmember is measured up and welded into place. The Rod Shop can adapt these independent front suspension set-ups for basically any car. They just have to adjust the length of the main beam according to how much space is between the two chassis rails. XR-XY Falcons are pretty common, so the boys already had the part ready to go

STEP

With the crossmember securely in place, the lower control arms are test-fitted and then measured to ensure everything is straight and where it should be relative to the measurements the boys made in Step 01

STEP

Next, the new upper control arm mounts are measured up and welded into place. The difference between new and old here is massive, with the new Rod Shop parts using close to double the amount of metal as the old. Then the upper and lower control arms are fitted and measured once more

STEP

Everything is looking good, so itís time to start the suspension assembly! Grmusaís airbag suspension is slotted between the control arms and the spindles are bolted in

STEP

Peteís XR Falcon uses giant six-piston Wilwood brake calipers, which the Rod Shop front end hasnít been specifically designed for, so a set of off-road-spec caliper brackets are modified slightly to suit

STEP

Now itís time to get to work on the new front mount power steering arrangement. The new front end already has the steering-rack brackets welded into it, so itís a case of sitting it in place, checking clearances and then grinding up an input shaft to suit. This new set-up uses a quicker ratio rack than before, and with the new IFS affording way more steering angle, itís going to make the Falcon much nicer to drive

STEP

How to properly torque your wheel studs into your hubs: Screw a couple of bolts into the unused bolt holes (these hubs are the multi-fit type) and sit them in a vice while you tighten the studs. Never go straight to the specified torque setting either; Bob here is doing each bolt up in three stages to avoid any distortion of the hub The front end also used a Gemini lower ball joint for the top control arm, which was very restrictive and the whole arrangement didnít have much adjustment. The steering arms were HR Holden items and the Commodore steering rack used resulted in short tie-rod ends, leading to all sorts of handling issues.

It was all a little like a Boxing Day dinner Ė bits from all over the place made to work together, but not necessarily work well.

To rectify this, Peter enlisted the boys at Castlemaine Rod Shop. ďI just told them I wanted it to drive nice, and steer properly,Ē he says. ďIt would never even hold an alignment; actually my F100 skid car, F-DIS, handles better. I want to be up there winning burnout comps, and I think making the car handle right is going to be a big help.Ē

Since doing the custom front end in Thomas Beltrameís FJ40 Toyota Land Cruiser skid rig, The Rod Shop has done a bunch of unique IFS set-ups that can be adapted to suit coilovers Ė or airbags like in Peterís car Ė and a range of different brake packages, including Peteís monster Wilwoods.

ďOur control arms are made from heavyduty, thick-wall steel imported from Spain, and itís all fully engineered to hold the weight of these big heavy burnout engines the boys use,Ē The Rod Shopís Marc Waddington says. ďSo itíll do the job better and handle much nicer than Grmusaís old set-up ever did. Plus itíll be much easier to drive with the power steering weíre supplying.Ē

We hung out with the Rod Shop boys for a couple of days to see how one of their custom front ends goes into a car like big, heavy-duty pieces of Lego.

As for the ATRISK Falcon, Peter isnít giving away too much about his plans just yet. His main objective initially is just to piece the car back together and make sure it drives right.

From there, anything could happen. And knowing Pete, it probably will! s

STEP

Itís time to get dirty and grease the spindles, hubs and bearings.

The bearings will only fit one way, and itís important to remember to a rubber dust seal on the back of the hubs to prevent, er, dust s e put ck ust

STEP

The new hubs slide in and are held in place with a nut and lock pin

12 STEP

The final piece of the puzzle is the brakes!

Grmusaís giant Wilwood discs were machined and given a clean-up by the Rod Shop boys before they went back on the car. You can see why the caliper brackets had to be modified Ė these are some serious stoppers!

H OW TO SET U P A B U R NOUT CAR

BOB Telford (no relation to our own Editor Telfo, but similarly bearded) is the guy to speak to at Castlemaine Rod Shop when it comes to custom suspension tuning.

There are a thousand different ways to do it, but thereís one simple key to setting up a burnout car: The outside front wheel needs to be square with the pad during the tip-in. Just like a drift car, the steering is often close to the lock stops during this time, and the front wheels need to be square with the ground in order to achieve the maximum contact patch and therefore the best steering and brake control.

For Pete's car, Bob recommended 1-1.5į of negative front camber and 4-4.5į castor angle, so he'll get the most steering correction from the front end. When it comes to toe-in, it really depends on the car, but generally around 2mm is the go-to Ė you definitely donít want toe-out like Peter had with his rear mount rack and short tie-rod ends.

Most burnout cars use a live-axle rear end without much adjustment other than perhaps a set of coil-overs Ė though Pete uses airbags in his car. Generally you want the car set softer in the rear than the front. A stiff front end will help turn-in during the tip-in, though you donít want to set your rear too soft, as this will make the car twitchy when trying to carve wider arcs and may even prolong tyre life.

Itís a fine balance!