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removing steering box

Started by mjb765, January 21, 2017, 12:55:27 PM

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cataclysm80

Quote from: Brads70 on January 22, 2017, 07:58:17 PM
I wonder if that coupler has something to do with why your box was leaking? The stock set up allows for some flex in and out. That u-joint does not? I mention this as I'd hate to see you install the FF box then develop a leak down the road?

Yeah, with the factory coupler, the shoes move up and down inside the coupler every time the car hits a bump.  The steering needs a way to absorb the body flex that happens during regular driving.
Unless you're driving exclusively on a smooth flat race track, I'd suggest switching back to the stock coupler.

cataclysm80

Here's some more info from my car notes...

Mopar factory power steering is very low resistance and easy to operate, which is not great at higher speeds.  In 1973 a firmer feel steering box became available on police cars, but these have become harder to find and are usually worn out.  Firm Feel Inc has stepped up to the plate to make good steering boxes.  Stage 1 is the equivalent of the factory firm feel police box.  Stage 2 has a firmer feel, and Stage 3 is even more firm.  Which one to get?  Sales of Stage 2 and Stage 3 is about 50/50.  The company usually suggests that people start with the Stage 2.  It's a noticeable improvement, but it seems that most people with a Stage 2 want to step up to a Stage 3. 

Steering "Feel" isn't just a product of the steering box, it's also increased by other things like smaller steering  wheel diameter, more scrub radius (tire width), lower pump pressure, and fast ratio pitman arms (due to leverage).

1970, 1971, & 1972 E bodies & B bodies used a smaller diameter sector shaft, while 1973 & 1974 cars used a larger diameter sector shaft.

All of the power steering boxes were 16:1 ratio, which is 3.5 turns lock to lock.  (The TA box ratio is only different due to the pitman arm)

The TA steering box used on 1970 Trans Am Mopars and some 1971 340 cars is not firm feel, and is basically made from C body stuff, but with a unique sector shaft, head assembly, and housing.  It included some stops inside to make lock to lock be 2.625 turns, and came with a special fast ratio pitman arm which reduced the steering ratio to 12:1.  This fast ratio pitman fits the TA boxes sector shaft, and may not fit onto other steering boxes.  This factory fast ratio setup did not include a longer idler arm, so right turns were fine, but left turns more than 20 degrees produced tire scrub.
Again, Firm Feel Inc stepped up to the plate to fix the problem.  They offer fast ratio pitman arms with small and large sector shaft diameters to fit many Mopars.  They also have a matched idler arm to fix the tire scrub problem that the factory unit had.  These Firm Feel Inc parts provide a 12:1 ratio with 2.75 turns lock to lock.
If you plan to use Firm Feel Inc's fast ratio products, the 1973 and up steering box with the larger diameter sector shaft is preferable because the longer arm increases the amount of force that the sector shaft must withstand.

For comparison...
new (2011 and up) Challengers have a 14.4:1 steering ratio with 2.75 turns lock to lock
new (2014 and up) Camaros have 16.1:1 ratio with 2.5 turns lock to lock
new (2015 and up) Mustangs have a 16:1 ratio
1988 Mustangs have 15:1
Neon's are 16:1.

cataclysm80

The stock 16:1 power steering ratio is comparable to most modern cars.

However, the number of turns lock to lock is different, and I find that odd.
Please help me to understand what is going on here.

Let's compare an E body to a new Camaro for comparison, since both cars have 16:1 ratio.

old E bodies have 16:1 ratio with 3.5 turns lock to lock
new (2014 and up) Camaros have 16.1:1 ratio with 2.5 turns lock to lock

Lock to lock is how many full revolutions of the steering wheel are required to go from steering all the way in one direction to all the way in the other direction.

Steering wheel diameter does not change the lock to lock number.  1 revolution = 1 revolution regardless of steering wheel diameter.  The steering shaft turns the same, even if the distance your hands move around the circumference of the steering wheel is different.

Front tire diameter does not change the lock to lock number.  (unless your tires are so big that the hit the frame rails as a stop)

If both cars have a 16:1 ratio, but the E body can turn its steering wheel further before hitting lock, does that mean that the E body has a tighter turning radius than a new Camaro?   
That seems unlikely, but what else could it be?


cataclysm80

Quote from: Brads70 on January 22, 2017, 07:58:17 PM
and another vote for stage 3 and the fast ratio arms while your at it!  :yes:

Brad, since you have Stage 3 with Fast Ratio, would you describe it as being more firm than a typical modern vehicle?
(fast ratio increases firmness due to leverage)

What is your front tire size (or at least width), and what steering wheel are you using?
These things also affect firmness.


I haven't personally tried the 12:1 fast ratio stuff yet.
2.75 turns lock to lock sounds nice, but 12:1 is quite a bit faster ratio than 14.4:1 modern Challengers, and even faster than most other 16:1 modern vehicles.
I was concerned that the 12:1 might feel darty, like the slightest movement would make big enough difference that it might be a chore to drive in a straight line.

Cuda Cody

  :worship:  @cataclysm80  you are amazing!  Where to you learn this stuff?  You're truly a huge asset to all of us that enjoy learning the finer details of E-Bodies.     :slapme5:

HP_Cuda


Oh the fabled one finger u-turn of lore!!!

:rofl:
1970 Cuda Yellow 440 4 speed (Sold)
1970 Cuda clone 440 4 speed FJ5
1975 Dodge Power Wagon W200

cataclysm80

Quote from: Cuda Cody on January 22, 2017, 11:20:51 PM
  :worship:  @cataclysm80  you are amazing!  Where to you learn this stuff?  You're truly a huge asset to all of us that enjoy learning the finer details of E-Bodies.     :slapme5:

Thanks Cody, through years of study, looking at cars, and talking with people, I've picked up a few things along the way.
Mainly it's the skill of organizing information, and being able to present it in a way that's easy to understand.

Tav 


Brads70

Quote from: cataclysm80 on January 22, 2017, 09:32:56 PM
Quote from: Brads70 on January 22, 2017, 07:58:17 PM
and another vote for stage 3 and the fast ratio arms while your at it!  :yes:

Brad, since you have Stage 3 with Fast Ratio, would you describe it as being more firm than a typical modern vehicle?
(fast ratio increases firmness due to leverage)

What is your front tire size (or at least width), and what steering wheel are you using?
These things also affect firmness.


I haven't personally tried the 12:1 fast ratio stuff yet.
2.75 turns lock to lock sounds nice, but 12:1 is quite a bit faster ratio than 14.4:1 modern Challengers, and even faster than most other 16:1 modern vehicles.
I was concerned that the 12:1 might feel darty, like the slightest movement would make big enough difference that it might be a chore to drive in a straight line.

Most performance GM boxes are 12:1 factory, thinking late 80's Iroc, GTA firebirds etc....
I don't find the steering hard to turn at all and I have 315/30/18 up front. No issue feeling to fast at hwy speeds either. I also have a slightly smaller steering wheel also 14 1/2" diameter.  I've driven it a few times to Carlsile  7 1/2 hour drive each way, feels more like modern steering IMO . Hope that helps.

Brads70

#38
Quote from: cataclysm80 on January 22, 2017, 09:17:23 PM
The stock 16:1 power steering ratio is comparable to most modern cars.

However, the number of turns lock to lock is different, and I find that odd.
Please help me to understand what is going on here.

Let's compare an E body to a new Camaro for comparison, since both cars have 16:1 ratio.

old E bodies have 16:1 ratio with 3.5 turns lock to lock
new (2014 and up) Camaros have 16.1:1 ratio with 2.5 turns lock to lock

Lock to lock is how many full revolutions of the steering wheel are required to go from steering all the way in one direction to all the way in the other direction.

Steering wheel diameter does not change the lock to lock number.  1 revolution = 1 revolution regardless of steering wheel diameter.  The steering shaft turns the same, even if the distance your hands move around the circumference of the steering wheel is different.

Front tire diameter does not change the lock to lock number.  (unless your tires are so big that the hit the frame rails as a stop)

If both cars have a 16:1 ratio, but the E body can turn its steering wheel further before hitting lock, does that mean that the E body has a tighter turning radius than a new Camaro?   
That seems unlikely, but what else could it be?
I found what limits how far the wheels turn on an e-body is the little nub on the lower ball joint that hits the lower control arm. The lower control arm is shaped for this nub/bump on the lower ball joint. In my compo I used A-Body lower control arms because they are slightly longer to go with the C-Body spindles I'm using , helps get my camber. Now on the A-body lower control arm that contact area is shaped opposite to a E/B body lower control arm. So in my case to get the turning radius back I milled down the nub on the ball joint . I'm sure there are stops in the steering box also but I found the lower ball joint/steering arm contacts the lower control arm first before it " bottoms out" on the stops in the steering box.