Fast Ratio Power Steering Boxes

[erik70rt]

Based on a thread I saw here that talked about fast ratio being required on all T/As that had power steering, it got me wondering about putting one in my T/A convertible project.  Are these hard to get?  Does anyone reproduce them?  Can I have my regular PS box converted? 

[autoxcuda]

Based on a thread I saw here that talked about fast ratio being required on all T/As that had power steering, it got me wondering about putting one in my T/A convertible project.  Are these hard to get?  Does anyone reproduce them?  Can I have my regular PS box converted?

Fast Ratio was an option.

It comprised of a box with modified end stops and a longer steering arm.

You don't need the box to get fast ratio. The original T/A boxes are very expensive and not necessary really to get what you are trying to accomplish

[Cuda Cody]

You and I misunderstood that thread the same way.  Fast ratio is both the standard power steering (16:1 Build sheet code S77) and the fast ratio quick ratio power steering (12:1 build sheet code S74) that we are both thinking of.  So any "power steering" on an E-Body is considered fast ratio, but it's not the fast ratio (quick ratio 12:1) you and are I thinking of that has the stamping on the box.  TA and AAR's came with both power steering options (S77 and S74) and are both considered fast ratio.  Only on an A-Body could you get fast ratio manual steering (16:1).

[erik70rt]

Thanks, Cody!  Whew!  I was hoping not to have to search for a new box!  I'll go with what I have!

[6bblgt]

on a T/A Challenger - manual steering was STANDARD
S74 "fast ratio" was the only power steering OPTION EDIT: I'll have to see where I got this from 

on an AAR 'cuda - manual steering was STANDARD
S77 power steering was an OPTION
S74 "fast ratio" power steering was also an OPTION

[Bullitt-]

this might be what your looking for   http://www.firmfeel.com/e_body_mopar_fast_ratio_pitman_idler_arm.html

They also can upgrade your box for tighter feel  http://www.firmfeel.com/e_body_mopar_power_steering_box_rebuild.html

[erik70rt]

Thanks!  The arms should be just what I need. 

[Cuda Cody]

This does not happen very often, but @6bblgt  and I are going to agree to disagree.  S77 was an option on T/A's too.

on a T/A Challenger - manual steering was STANDARD
S74 "fast ratio" was the only power steering OPTION

on an AAR 'cuda - manual steering was STANDARD
S77 power steering was an OPTION
S74 "fast ratio" power steering was also an OPTION

[Cuda Cody]

 

[6bblgt]

when the "FAAST RATIO" subject came up in the other thread I looked for where I got that info in my head

still looking 

[Cuda Cody]

I'll be the first to admit you still know more than me.    I'm thankful you share the knowledge you have and help all of us in the hobby out with everything you do. 

when the "FAAST RATIO" subject came up in the other thread I looked for where I got that info in my head

still looking 

[Fastmark]

Ok, you guys need to figure this one out. You're making my head hurt here! Lol. So you're  saying that you could get STANDARD ratio power steering( that is called fast ratio) on the trans am cars as well? However, you could get a QUICKER RATIO power steering as an option, but it had an arm on it that had FAST RATIO cast on it that was longer just to make it the QUICKER ratio? I've got the  build sheet for my green car. It has the TA box with the FAST RATIO cast on the arm. On the sheet under the S77 column, it has a 4. So I guess that means my car is correct with S74 fast ratio, quicker ratio?

[dodj]

Thanks!  The arms should be just what I need.

If you run headers, check to see if the longer arms will hit them. Some brands do not work with the longer arms.

or...you dimple them. There was a thread about banged up headers (might have been cc.c). The dimples had no harmful effects on the headers other than appearance.

[Burdar]

It comprised of a box with modified end stops and a longer steering arm.

There are already "stops" built into the lower ball joints.  They are rounded raised sections on the inside of the ball joint that contact the lower control arm to  stop the wheel.  Why would there be a need to modify the boxes?  Not questioning you personally. 

Or, did the 1970 lower ball joints not have a built-in stop like the 73+ ones?

[Cuda Cody]

T/A's and AAR's = both same with 3 options and while both power steering options were technically quicker than the manual, I would suggest we keep calling it the same as the hobby has for many years. 

Option #1 = Manual Steering
Option #2 = Power Steering
Option #3 = Fast Ratio

All 3 could be ordered on T/A's and AAR's.

Ok, you guys need to figure this one out. You're making my head hurt here! Lol. So you're  saying that you could get STANDARD ratio power steering( that is called fast ratio) on the trans am cars as well? However, you could get a QUICKER RATIO power steering as an option, but it had an arm on it that had FAST RATIO cast on it that was longer just to make it the QUICKER ratio? I've got the  build sheet for my green car. It has the TA box with the FAST RATIO cast on the arm. On the sheet under the S77 column, it has a 4. So I guess that means my car is correct with S74 fast ratio, quicker ratio?