Welcome to the continuation of the build up of Bruce Stephens Racing new A.R.T Chassis – part 2 of a 3 part series. If you have just joined us, go back and read part 1 for the amazing history behind this Chassis. This week we get down close and follow the build with a pictorial showcase from “Go to Whoa”. There are a clearly a few ways of sequencing a Chassis build up, this is the one the BSR Team use.
The A.R.T Chassis is placed on roller frames at BSR to make it easy to move around the factory
First Job : Crew Chief Graham Summers tapes a packer to compensate for the A.R.T'S 1/2 INCH uprail (LH Chassis rail is 1/2 INCH higher than RH to help with clearance to track kerbs etc)
The A.R.T doesn't use the traditional diagonal bracing in front of the radiator. Instead, the use of a single piece "Drop Bar" provides increased front end flex
Getting all your bolts sorted up front makes for a quicker build up
Spuds provide a slip-in connection for bars. Drilling of nerf bar spuds (and all other spuds) followed by beburring makes the bars easy to fit and it's kind to the fingers. A hole is then drilled through the spud and bar when in position and then secured with a machine screw and nylock nut.
The mounting of the Master Cylinder is one of the first steps in setting up the brake system
The CNC machined engine plate is next to get secured
No surprises here - next it's the floor pan. The A.R.T Chassis's floor pan mounts up front underneath making it easier to get off in a built up car with the driveline in position - SMART !
In goes the steering box - this one is a full width Lee unit
Since the top wing on a 410 Sprintcar gets a hydraulic actuator that is motivated by the power steering system, it usually gets bolted in about the time the steering box "gets the nod"
Here Graham Summers starts setting up the throttle pedal linkages. You will note that the steering box, pump and hydraulic hoses are all secured
Graham and Crew Member Matt Stock position the rear end into the A.R.T
Once the diff (rear end) is in position, the drive line and torque tube housing can be bolted up
Viewed from the front of Engine Plate the driveshaft is clearly visible along with the drive for the power steering and fuel pump. The later can be seen above the driveshaft - they are driven off the camshaft
The in-out gear lever and control cable to the diff is secured
Torsion bars and rear torsion arms are tapped into place and tightened on the their splines. The squaring of the diff and locking it in place with radius rods is a critical process to car set up and involves much debate as how best to do it
The Jacobs Ladder holds the rear end laterally in the car. The A.R.T Chassis had an option of two fixing locations. The choice is made depending on track condition. Usually the inboard mounting point is selected. Here the lower mounting quick release pin is being locked in position
Now we're gettin' serious ! The JSR (John Sidney Racing) 410 is out of the shipping crate and ready for "docking". The rocker covers are removed to get clearance to "shoe horn" the engine in. Graham and Crew Member David "Buzz" Aldersley take care to guide the engine through the down tubes of the Chassis
The engine has docked with the driveline and is now in the process of being secured to the frame. The engine is bolted to the engine plate and has a couple of direct mounts at the front. No rubber mounts for these babies - it's all metal to metal contact !
She's in ! The JSR killer 410 sits proud in the A.R.T. Rocker covers are reattached - Looks COOL ! The JSR uses the latest Kinsler "BEAST" fuel injection - the same type that Jason Meyers just won the WoO Championship with. There are 16 fuel injection nozzles - 8 down nozzles and 8 up nozzles. The up nozzles are inboard of the Ramtubes on the JSR mill, but it can be configured to go outboard if you prefer. This thing is on Motor Steroids and uses the best of the best.
JSR did a full rebuild after the engine broke a crank last season. Here are some of the "war wounds". The broken crank is on the right, piston in the middle and what's left of the conrod on the left. It was a bit of a mess ! Team Owner Bruce Stevens freely admits that these parts were past their use by date when they gave up
Inside the cabin is taking shape. Brakes, power steering system, wing adjuster, throttle pedal, fuel pump and more are all good to go. Good one guys !
Now it's the front ends turn. Here the boys have placed the front axle into the frame and started connecting the radius rods that set the units fore and aft position. The radiator has also been loosely located
Next up it's the torsion bars and arms on the front. Behind the axle you can see both radius rods are in position, but their length has not been set. Also just out of shot, the front wing is in position
Graham sets the length of the upper right radius rod and then locks them in position. This will set the front end in both it's fore/aft and rotational position
The height of the axles determines the ride height of the racecar. Adjustable blocks are used to set a desired distance of the front end beam to the frame before the torsion bars are adjusted
With the blocks in position, the torsion arm resting on the top of the axle, the torsion stop is wound in to just give a touch of interference. Then the locknut is tensioned
That gets the car to a reasonably advanced state. The front and rear ends are in and set up, the engine and drive line are in position, and power steering and brakes have been connected. Join us next week as the build up is completed and the fuel tank, wheels, wings and panels go on to make this beast the recognisable machine that we all love to watch. See you next week for the final installment of BRUCE STEPHENS RACING – V91 A.R.T CHASSIS BUILD UP