[PairsNPaint]

I'm planning to build a '27 Track T roadster. I've noticed that all T bucket chassis I've seen utilize a front suspension with the tie rod running out in front of the axle as opposed to Model A - and later chassis with the tie rod behind the axle (which seems much cleaner looking and safer to me). Can anyone explain why this is so and is there any reason the tie rod can't be located behind the axle on a T chassis??

Thanks!

 

[pasadenahotrod]

The tie rod is in front on many Ts because the springs are behind and often below the axle thus making it a problem to modify the steering arms on the spindles to drop them to allow for clearance of the tie rod.

Model As, and 32-34 Fords have the spring above the axle and clearance problems only occur with dropped axles and split wishbones, hairpin radius rods are usually not a problem.

It takes some planning and mockup to "perfect" a rear tie rod install on a suicide style spring behind axle front end. The Track Car has a stock 47-48 axle with 48 dogleg split wishbones and spring behind the axle. It uses unmodified spindles and a "bent" ends tie rod. The bends neccessitated the installation of a support bridge between the ends along the length of the tie rod as iit would flex (not a good idea) without it. Problem solved and runs, drives, steers very well. The drag link on the Track Car is cross steering from a front mounted Mustang/Falcon box and attaches to a fabricated boss on the tie rod rather than the right spindle arm.

The Track Car is a very well designed 23 with a turtle deck and full nose/hood which tilts forward for engine access, built in 1969-70 by Burl Bell in Houston TX.

 

[PairsNPaint]

Thank you, that helps a lot. Which Track Car are you refering to? Do you have a link to any pictures, esp. of the front end?

 

[timothale]

tie rod

tie rod in front usually makes the tires scrub when you turn check out akerman design and suspension threads I have driven go carts with tie rod in ftont and they would slow down in corners because of tire scrub. handling can be scarry on bumpy roads turning if not set up right.
retired Ford engineer.

 

[Youngster]

Front axle question re:Track T roadster

Running the tie rod behind the axle is not hard to do. Basically you have 2 choices.
1.) reshaping the steering arms on the spindles
2.) purchasing a pair of dropped spindle arms from Chassis Eng.

Either one of these options work well. There is a bucket still in service that I heated and reshaped the arms on 35 years ago and no problems. Just make sure you let the heated portion cool by it's self. DO NOT quench them!

Most often when tie rods are in front of the axle, it's because Chevy spindles were used. I have never used these spindles,so I'm not sure why no one has reshaped them. I do suspect it could be because there could be a clearance problem. Don't quot me on that though.

Youngster

 

[Dugg]

I concure with Yougster on using the Chassis Engieering steering arms. They're forged, not cast. CE offers their arms in two "drops". One mounts the tie rod about 1.5" below the centerline of the backing plate mounting holes in the spindle. The other about 2.5 ".

Aside from being forged, the other point I like about CE is that the arms mount with through bolts. That is, you put the bolts through the backing plate (or caliper mount) through the spindle and through the steering arm and put locking nuts on the bolts. I prefer the nuts be exposed as opposed to putting the nuts inside the drum because you can see the nuts and the prescribed three threads of the bolts during your pre-flight.

Othe brands of steering arms are cast (some may be forged, the info is a tad sketchy here) and they are mounted with bolts from the backing plate side into blind holes in the arms. Should a bolt or bolts loosen, you may not catch'em in time. These may look a bit cleaner, but I prefer the logic of the bolt and nut design.

Yes, I do tend to ramble on.... sorry.

With the tie rod out in front, you no longer have the correct steering Ackerman (sp) geometry. As I recall, in a top view of the car, this amounts to lines drawn through the king pins center lines through the steering arm/tie rod mounting holes to converge at the companion flange of the rear end.

With the tie rod out front, it is conceivable to heat and bend the steering arms to produce the correct Ackerman but in doing so, you probably won't be able to mount brakes or maybe even wheels on the car.

 

[Youngster]

Track T roadster

Well written Dugg, Guess I should have included an explanation. I'm sure PairsNPaint can find something on here about the Ackerman principal if he wants to.

Youngster