Been studying Shane's firm feel/steer gear post

[BIGSHCLUNK]

I have found it very interesting so thanks Shane for getting that going. Seeing I'm SLOWLY on the way to pulling mine out (leaky POS) (lucas slowed it for a year!) I thought I'd do a little recyclers research... (on power boxes that is).

So my program lists 67-72  15.7-1
HEMI 67-71 15.7-1
T/A 70-71 (no ratio listed)

Is this where the Std. Firm. Extra Firm come from?? The first 2 have the same ratio listed.. so is it made up by that valve thingy on the top?? Is it necessary to have your P/S pump "match" your stg box?? My interchange would make me think no.... but lots have changed since 1970...   

[ChallengerHK]

Hey, schlunk. I think ratio and "feel" are different topics. Ratio is the speed of the system response, how many turns lock to lock of the wheel. Feel (or firmness) is more the quality of the system response. Chryslers are somewhat famous for power steering with a sloppy feel, a lot of steering wheel movement that does not translate to tire movement. "Feel" seeks to correct this issue.

[cudazappa]

Chrysler achieved a different ratio on the T/A & AAR cars by using a longer pitman arm.  The steering boxes had modified stops so the tires wouldn't over travel.

The "firmness" is the amount of effort you need to turn the wheel.  Nothing to do with loose play in the steering box.  This is done by using different springs in the power box.  Chryslers were known for being over-powered, needing very little effort to turn the wheel.  What this also translates to is steering numbness to the driver, as the tires can't provide feedback of what they are doing to the driver through the steering wheel.  By making it firmer you get better steering response which helps the driver know what the front tires are doing.

[ChallengerHK]

That's a much better explanation than mine, cudazappa. I tend to think of sloppy steering and unfirm steering as the same, and they're really not.

To be perfectly clear, you are concurring that ratio and feel are two different things, though?

[tommyg29]

yep, I just installed the extra firm and it only provides for more steering effort. Same number of turns lock to lock, and still a HUGE turning radius. I like the feel.

[cudazappa]

That's a much better explanation than mine, cudazappa. I tend to think of sloppy steering and unfirm steering as the same, and they're really not.

To be perfectly clear, you are concurring that ratio and feel are two different things, though?

completely
ratio is the amount of turn of the tires to the turn of the wheel.
feel is the feedback/effort your hands feel when turning

[BIGSHCLUNK]

Ok, some good info here.. I understand the T/A arm difference.. So what made the difference between the regular box and the HEMI box?? (same ratio / same lock to lock)? Was there a different "feel"?? In all my programs HEMI IS HEMI ONLY.