Make an EBay search for "rack, pinion, (appleton, coleman, sweet, woodward)". Sometimes you might get lucky in that market.
Part of your experience will be determined by the length of the steering arms out by the wheels, as well as the diameter of the steering wheel. A quick rack, with short steering arms and a small steering wheel might equal an undrivable car (especially without power steering).
Having said that, here are my research notes (feel free to help me perfect them):
******************
Rack speed is measured in inches per turn. If you turn the pinion (1) time, the rack shaft will move between 1-3/4" (slow) and 3-1/4" (fast).
The f body had 2.25 lock to lock and 2.75 lock to lock ratios.
Two Ratios: 2.9 (recommended for road use) and 2.4 (recommended for racing) the f-body rack is 58" while pre 88 fieros were 52" for entire length with ends.
Escort Mk2 Steering rack for use on the Haynes Roadster. The inner ball joint width that I measured was 585mm. Escort rack is the right length (inner balljoint to inner balljoint) for the +4" chassis... the Escort is within 6mm of being perfect for the McSorley 7+4 chassis and hence it must be 94mm too big for the standard chassis.
Chevette rack is 3.75 turns lock to lock with 6" of rack travel over those 3.75 turns. Based on this the rack is traveling 1.6" per turn 6/3.75=1.6.
Fiero is 3 turns lock to lock.
The 'un cut' Chevette rack is pretty close to 41" tip to tip. I had to cut about five threads off each end for my fitment. The pinion shaft tube base starts right at 11.5" in from the end if the rack. As far as angle, that is only a guess from eyeballing it. I would say around 5 to 7 degrees angle off the rack body. 26" as measured from feeling through the boot. Per rough measurement, Chevette is, approximately, 24 3/4". The one I have is about 25" C to C on the inboard ball joints
Front steer: - Chevette rack (need to be shortened) - Miata (need to be shortened) - MGB - Triumph Spitfire - Porsche 914 (center-input) - RX-7 Gen II shortened 4.5" - Volvo 240 shortening?? - BMW 3 series shortening?? - pre 84 tercel 84' Mustang. It is front steer however... I found that pinto rod ends will bolt right onto the Mustang rack and reduce its width by about 2" inches on each side. This works perfectly on my book +4 chassis.
The F Body rack "Body" is 22.25" from stop to stop. The body itself is the steering stop. The F Body "rack gear" is 27" from stop to stop. The inner tierods have a plastic bushing that acts as a abocusion for the bump stop. So this is the lenght of the rack with the inner tierods on it.
The F Body total travel is 4.74 The F Body WS6 takes 2.25 turns lock to lock. The F Body has 3.75" of rack body on the left side of the pinion. The F Body has 18.5" of rack body on the right side of the pinion.
The Chevette rack body is 17.75" The Chevette rack gear is 23 3/8" The Chevette total travel is 5.65"
The Chevette has 2" of rack body on the right side of the pinion. The Chevette has 15.75" of rack on the left side of the pinion
The 88 (Fiero) rack body is 24.25" The 88 rack gear is 29.25 The 88 total travel is 5.1 The 88 takes about 3.4 turns lock to lock The 88 has 2.75" of rack body on the left side of the pinion. The 88 has 21.5" of rack on the right side of the pinion.
The 87 (Fiero) rack body is 23.75" The 87 rack gear is 28.25" The 87 total travel is 4.6" The 87 takes about 3.1 turns lock to lock The 87 has 2.25" of rack body on the left side of the pinion. The 87 has 21.5" of rack on the left side of the pinion shaft.
Mustang II Mustang II A-arm spindle = aprox. 4-7/8" 24.5 from tie rod socket to tie rod socket
Flaming river MII 4.00 turns lock-to-lock, rack travel 5.25", overall length 45", inches per turn, 1.3”
Factory Pinto..... 4-1/8 to 4-1/4 turns lock-to-lock. One full pinion shaft turn = aprox. 1.262" of rack travel.
F-body: 4.74/2.25 = 2.106"/turn '88: 5.1/3.4 = 1.5"/turn '87: 4.6/3.1 = 1.48"/turn Chevette: 5.65/3.5 = 1.614"/turn
power-steering Miata rack Total travel = 4.71" 2.66 turns lock-to-lock. 26" pivot to pivot. Speed = 1.77"/turn
Rack and Pinion Ratio Chart
1.57 inches per turn: Very slow steering, mainly for superspeedways or road courses (GT classes) where top speeds exceed 160 mph. Ordinarily applied as manual steering. Also used to compensate for the short steering arms on small cars. With long steering arms, the overall ratio can range down to 24:1. For power steering with this rack on short tracks, use a #850 or #855 servo valve with a KRC standard 7.2cc pump and #8 and smaller output fitting; The same servo valve with a KRC 5.9cc pump and a #4 or #5 fitting will handle a ratio like this on superspeedways.
1.83 inches per turn: Slow steering for paved tracks 5/8 mile and over; usually run as manual steering. Formerly popular in GT classes, as this ratio closely approximates that of OEM sports car steering when used in conjunction with short steering arms. Use #850 or #855 servo valve with KRC 7.2cc or 5.9cc pump and #8 and smaller output fitting.
2.09 inches per turn: Formerly the most popular ratio for manual steering pavement applications in both stock car and road racing. Known as the 16:1 rack, it feels about like a Corvette. Used with power assist about half the time.
2.36 inches per turn: Quicker steering for paved tracks, especially those 1/2 mile and under. Useable as either manual or power steering, although run as power steering in 80% of cases. Its overall ratio usually works out to around 14:1. For power steering, use a #855 servo valve with a KRC 7.2cc pump #7 and larger output fitting
2.62 inches per turn: Ten years ago this ratio was commonly used as manual steering on dirt late models. At 12:1, it still gives relatively easy steering on dirt, and is the best entry-level choice for manual steering limited late models. It's most common application today is on pavement with power assist. Use a #855 servo valve with KRC 7.2cc pump and #8 and larger output fitting.
2.88 inches per turn: Quicker than average manual steering for dirt tracks. At about 10:1, this will require setting the car’s caster and camber for minimum effort, unless power assist is used. Much faster steering than any road vehicle. For power assist on pavement, use a #855 servo valve, on dirt use a #850, with a KRC 7.2 pump and #8 and larger output fitting.
3.14 inches per turn: For powersliding around bull rings. This is about the fastest ratio usable as manual steering (and was considered radical in the early 1980’s). If used without power assist, most front ends will need the positive caster backed way off to street-vehicle levels (under two degrees), and the caster split reduced.
3.40 inches per turn: Very quick response; generally applicable only to dirt and only with power assist. Cuts your reaction time in half if you’re ready for it.
3.66 inches per turn: Instant response with even less wheel movement, standard equipment on many new late models. Best with large amounts of power assist, such as 100-125 PSI.
3.92 inches per turn: See Figure 7. Needs a soft torsion bar (220 and smaller) and a KRC 9.6cc pump with #10 and larger output fitting.
The Chevette rack has a 3/4" 30 Spline male head coming from it. and the Old Fiero rack uses a 3/4" DD... DD rod and Vibration U Joint from Flaming River You will need the U-Joint to be 3/4 " - 30 X DD (PN# FR1814 3/4"-30 X 3/4"DD)
_________________ *************** Geek49203 aka Tim Wohlford Louisville, KY Hayes front, S10 +2 rear, Lalo body.
|