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Open-Track; Level 2
The Open-Track level 2 blueprint will take you to the next level of performance. It
is a continuation from level 1, with some important changes and additions as noted. (Please refer to Open-Track; Level 1 modifications 1 thru 8 as a starting point).
(1) Brakes: Good braking is a key element in reducing your lap times. You can probably shave more off your lap times per dollar spent on braking, than dollars spent on your engine. Imagine it takes your engine 12 seconds to get up to speed down a straightaway and then your brakes 3 seconds to bring that speed back down. If you can stay on the gas 2/10th second longer than the car next to you, before braking, then you can easily pass him, (2/10th will equal 35ft). With this in mind, you want the best brakes your budget can afford.
Disc brakes are a must! Probably the best bang for the buck would be the 1965-67 Mustang (and Fairlane) front disc brakes together with 2-1/2” X 10” rear drums. This is what Shelby used back in the day and is still used currently in vintage racing, with good success. These 1965-67 Mustang units are 4-piston calipers made by Kelsey Hayes and are still available at your local auto parts store at a reasonable price.
Caliper brackets are then needed to bolt the calipers to your drum-brake spindles. While original Ford brackets are getting scarce, they are available from aftermarket mustangs suppliers.
The rear drums and backing plates are mid-60s full-sized Ford and stationwagon units. Rear drums and wheel cylinders are readily available at your local auto parts store. Porterfield Racing Brakes has several compounds of high-performance pads & shoes and a helpful staff to help you choose the best for your application. www.porterfield-brakes.com
Other disc brake options include: 1968-71 Mustang, complete spindle and disc brake set-up (1 piston). 1975-etc Granada complete spindle and disc brake set-up (1 piston). In my opinion, these 1 piston Calipers are not as good as the above Kelsey Hayes 4-piston units. Another option would be aftermarket Wilwood disc brake kits, however beware you need to get up to the high-end Wilwood units before you will exceed the Mustang 4-piston Kelsey Hayes units. Do your homework before you buy.
Master cylinder: If non-power disc brakes are desired, install a duel reservoir 15/16 master cylinder (ie 1975 Granada).
Proportioning Valve: If you are having problems with rear brakes locking up under hard braking, install an adjustable proportioning valve (supplied by Wilwood, etc).
(2) Oiling: if you are getting serious about high-performance, now is the time to install a road race T-pan to protect your engine from oil starvation during hard cornering. Canton brand is good, Aviaid is better/more expensive. Also the mechanical oil pressure gauge as described in Level 1.
(3) Tires: (same as Level 1)
(4) Sway Bar: A 1-1/8 inch diameter (same as Level 1)
(5) Suspension: Replace any/all worn out or sloppy front suspension parts. You cannot expect your car to handle well with sloppy suspension parts, use polyurethane replacement parts where applicable.
A-Arms: While the upper A-arms are removed, re-drill/ relocate the mounting holes 1 inch lower as done on 65 Shelbys.
Springs: Now is the time for stiffer springs front and rear. Front coils; 600#-650# ( as you cut the coil spring to lower the car to the desired ride height, the spring rate will increase approx 50#) Rear leaf; 4-1/2 leaf (has 1/2 leaf forward to control spring wrap under hard acceleration) also, if you purchase the reverse-eye spring, less or no lowering block will be required to lower the rear of your car.
Shocks: The original “single adjustable” Koni Shocks used on early Shelbys are hard to beat for the price. I’ve also had good luck buying good used Koni shocks off eBay at half price.
Optional; (a) Install a bump-steer kit. (b) Install a Shelby quick-steer kit = Pitman arm & Idler arm, together with a 1965-66 power steering gearbox.
(6) Strut-Rods: The stock front strut-rod bushings are especially troublesome. They are so soft and flexible, that it allows excessive fore and aft movement of the lower control arm, therefore your front end geometry is constantly changing especially under braking. A cheap fix is to disassemble the strut-rod bushings and cut the inner tube spacer a little shorter (shorten as needed – (as I recall about ½”) so that when reinstalled, the rubber bushings will be squeezed tighter and be much firmer.
There are several aftermarket suppliers attempting to solve this problem with different designs, even the most expensive have their pluses and minuses and leave much to be desired. In my opinion, the best solution is mounting a hiem joint at the correct factory pivot point, this is low cost but requires fabrication and welding. This will be discussed in greater detail in the “vintage racing” suspension forum.
(7) Alignment: After you replace front suspension parts, (and assuming you have already got your car lowered to desired ride height), you need to realign the front end for high performance street/track car settings: Caster; 3 degrees positive, Camber; ¼ – ½ degrees negative, Toe-in; 1/8 inch.
(8) Engine: After you get your car braking and handling well, then you can start adding more power. The quickest and easiest improvements come from Intake manifold, Carburetor, Exhaust headers, Camshaft. The engine forum would be a good place to get detailed specific information regarding your specific engine needs.
(9) Transmission: I assume it’s common knowledge that automatic transmissions are not suitable for high-performance road racing. Manual 3 speeds have much too “wide” spread between the gear ratios. Manual 4 speed “wide” ratios are less desirable than the “close” ratio transmission. The old 1965-73 Ford toploader 4spd close ratio is probably the best bang for the buck, it is much stronger than the old Borg Warners or the T-5 speeds. The new Tremic 5spd close ratio is very good, but more expensive.
(10) Rear End: If you haven’t already, you need to upgrade to a 9inch rear end, with either a Detroit Locker, DPI black gold, Auburn, etc or a spool (you must decide on either 28 or 31 spline axles before you buy).
Notes; The Ford factory (clutch type) limited slip or traction lock differentials do not hold up very well. 28 spline axles will work, but 31 spline is better/stronger. Axles (and brake backing plates) from an 8” housing will interchange with a 9” housing of the same year/width, including either 28 or 31 spline.
Misc: For miscellaneous parts needed, www.SpeedWayMotors.com has a great “Race & Oval Track” paper catalog.
PLEASE FEEL FREE TO JOIN IN AND ASK QUESTIONS.
9/18/2011, 9:50 pm
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