Fast Ratio Pitman Arm...

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RustyRatRod

RustyRatRod

I was born on a Monday. Not last Monday.
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I should know the answer to this, but I do not. Will a fast ratio pitman arm be of any benefit in my Valiant, even though it has the standard steering box? @72bluNblu?
 
IIrc i think you have to have the steering box also for it to make a difference.
 
It will if you want faster steering. It is longer so I guess you'd need to check for fit and interference, and the RIGHT way to do that would be to have a matching idler. I've no idea on the large vs small spline ??
 
67Dart273 said:
It will if you want faster steering. It is longer so I guess you'd need to check for fit and interference, and the RIGHT way to do that would be to have a matching idler. I've no idea on the large vs small spline ??
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There are both spline sizes available. But, to my knowledge, no one makes a fast ratio idle arm for the early A.
 
RustyRatRod said:
There are both spline sizes available. But, to my knowledge, no one makes a fast ratio idle arm for the early A.
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If it's any consolation, the AAR Cudas and T/A Challengers used the fast- ratio pitman with the standard idler. Not ideal, but was good enough for the factory.
If you're running headers, I can just about guarantee there'll be interference.
 
Professor Fate said:
If it's any consolation, the AAR Cudas and T/A Challengers used the fast- ratio pitman with the standard idler. Not ideal, but was good enough for the factory.
If you're running headers, I can just about guarantee there'll be interference.
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Nope, no headers.
 
Check the length of the pitman arm, and see if there is an idler from a bigger bodied car the same length. I put a fast ratio pitman arm on my Challenger, with a PS box. I knew it would do the wopsided turn one way farther than the other thing, so I had a buddy that worked at the parts house look thru the books to see if we could match an idler arm. He found one off of either a later B body like a Cordoba, or a C body. Snatched one off the shelf and it was the same length as the fast ratio pitman arm. This was all back in 90 or 91. If I had it to do over again, I would have left it alone on a PS car. As twitchy as Chrysler PS is anyway....with the longer pitman and idler, you can look at the steering wheel and be half way in the ditch if you ain't watching what you're doing! I'm not sure how it would act on a manual steering car? You might also check to see if anybody makes a longer idler arm for a 67 A body, and see how the length matches up. I think 67 is the only year of later A's that have the same style idler arm bracket as early A's. Maybe that would work if you're lucky enough for them to be available.
 
RustyRatRod said:
I should know the answer to this, but I do not. Will a fast ratio pitman arm be of any benefit in my Valiant, even though it has the standard steering box? @72bluNblu?
Click to expand...

By standard you mean just the regular old 16:1 power steering box right?

On the AAR’s they were used to change the 16:1 power steering boxes to an effective 12:1 ratio. The AAR steering boxes weren’t that different, they had the same ratio as the standard power steering box but if I recall correctly the internal stops were changed because of how the longer pitman changes the throw.

On a standard power steering box they still give the same effective ratio, 12:1.

If you’re talking about a 24:1 manual box, I think you’d end up at 18:1? It’s a percentage change on the lever arm, not a straight 4:1 reduction. So on a 16:1 box it’s a 25% reduction, it should be the same percent reduction regardless of the ration of the box.
 
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72bluNblu said:
By standard you mean just the regular old 16:1 power steering box right?

On the AAR’s they were used to change the 16:1 power steering boxes to an effective 12:1 ratio. The AAR steering boxes weren’t that different, they had the same ratio as the standard power steering box but if I recall correctly the internal stops were changed because of how the longer pitman changes the throw.

On a standard power steering box they still give the same effective ratio, 12:1.
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I thought the standard manual boxes were 24:1? Is that not the case? Have I been misinfornicated?
 
JDMopar said:
Check the length of the pitman arm, and see if there is an idler from a bigger bodied car the same length. I put a fast ratio pitman arm on my Challenger, with a PS box. I knew it would do the wopsided turn one way farther than the other thing, so I had a buddy that worked at the parts house look thru the books to see if we could match an idler arm. He found one off of either a later B body like a Cordoba, or a C body. Snatched one off the shelf and it was the same length as the fast ratio pitman arm. This was all back in 90 or 91. If I had it to do over again, I would have left it alone on a PS car. As twitchy as Chrysler PS is anyway....with the longer pitman and idler, you can look at the steering wheel and be half way in the ditch if you ain't watching what you're doing! I'm not sure how it would act on a manual steering car? You might also check to see if anybody makes a longer idler arm for a 67 A body, and see how the length matches up. I think 67 is the only year of later A's that have the same style idler arm bracket as early A's. Maybe that would work if you're lucky enough for them to be available.
Click to expand...

Thanks for that! That's an option I hadn't thought of.
 
The pitman to headpipe clearance is going to be a big issue to plan for.

what exhaust manifolds or headers do you have?

Most likely it’s not going fit without well thought out custom headpipe.
 
RustyRatRod said:
I thought the standard manual boxes were 24:1? Is that not the case? Have I been misinfornicated?
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I think that would get you back to around 20:1 ratio. Might as well buy a new 16:1 box. Then in the future you have stock replacement pitmans at 1/3-1/4 cost of fast ratio pitmans.
 
autoxcuda said:
I think that would get you back to around 20:1 ratio. Might as well buy a new 16:1 box. Then in the future you have stock replacement pitmans at 1/3-1/4 cost of fast ratio pitmans.
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So then I am correct on the 24:1 ratio?
 
autoxcuda said:
The pitman to headpipe clearance is going to be a big issue to plan for.

what exhaust manifolds or headers do you have?

Most likely it’s not going fit without well thought out custom headpipe.
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Manifold. Slant six.
 
Whoops sorry. I was still editing my post and see there’s a bunch of responses. Check my post again, but a standard manual box at 24:1 would end up around 18:1 if my thinking is right, it’s a percentage reduction based on the length of the lever arm.
 
It's sounding like my best bet is to get the 16:1 box.....so do any of yall have a 16:1 manual box and how does it handle particularly at low speeds?
 
RustyRatRod said:
It's sounding like my best bet is to get the 16:1 box.....so do any of yall have a 16:1 manual box and how does it handle particularly at low speeds?
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I have a 16:1 manual box in my car. I think it’s great, as you probably know I also run 275/35/18’s up front and +6.5*’s of caster and I can still get around parking lots just fine. Below 10mph or so the steering effort definitely gets a lot higher, but if you plan ahead and don’t try to dry steer it at a standstill it’s ok. I don’t know if I would want to parallel park it everyday but I wouldn’t want to do that anyway.
 
72bluNblu said:
I have a 16:1 manual box in my car. I think it’s great, as you probably know I also run 275/35/18’s up front and +6.5*’s of caster and I can still get around parking lots just fine. Below 10mph or so the steering effort definitely gets a lot higher, but if you plan ahead and don’t try to dry steer it at a standstill it’s ok. I don’t know if I would want to parallel park it everyday but I wouldn’t want to do that anyway.
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The largest tire I plan to run on the front will be around 26.5" tall.....IF it will fit.....but narrow.
 
RustyRatRod said:
It's sounding like my best bet is to get the 16:1 box.....so do any of yall have a 16:1 manual box and how does it handle particularly at low speeds?
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I’ve got the 16:1 PST box in my 65 Dart 273 V8 I really like it. I didn’t find it much harder to turn than stock, and I’m a skinny arm fellow.
 
Dartsun said:
I’ve got the 16:1 PST box in my 65 Dart 273 V8 I really like it. I didn’t find it much harder to turn than stock, and I’m a skinny arm fellow.
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Well I'm not and I have pretty big powerful arms but I'm worried for Kitty if she ever drives it. I'll just have to tell her not to try to steer unless it's rolling.
 
16:1 is hard in tight places at low speed. They make a 20:1 manual box, Firm Feel is building one for me now. not sure if you can get a fast ratio arms for an early A. PS boxes are 16:1.
 
And, you can modify your PS box to be way less sensitive, by adding reaction discs, as many as you like, until you like the feel of it. Initially I added two to mine, but later in the week, I added more. I don't recall if it was two more or Just one.
 
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