View Full Version : Rack and pinion steering with dropped tube axle


Psych
10-27-2004, 09:41 PM
Just got a 36 Ford coupe. Bought it fot the sheetmetal. Front end has a dropped tube axle, coil overs, hairpins
and a rack and pinion attached to the front cross member.
Panhard also. Parts are new and very solid but using a rack
and pinion steering with a straight axle is a concern. Should
I be concerned? Any help or comments would be appreciated.

50dodge4x4
10-27-2004, 09:48 PM
I think I would expect some seroius bump steer. Gene

metalshapes
10-27-2004, 09:51 PM
[ QUOTE ]
using a rack and pinion steering with a straight axle is a concern.
Should I be concerned?

[/ QUOTE ]


Yes, get rid of it.
It will give you horrible Bumpsteer with a Straight axle.
We had a long discussion about this not too long ago.
Maybe somebody can help you find the thread...

porknbeaner
10-27-2004, 09:51 PM
[ QUOTE ]
I think I would expect some seroius bump steer. Gene

[/ QUOTE ]
Ditto
The only way I know of to not do bump steer with a rack and a solid axle (live axle?) is to mount the rack to the axle.

Fat Hack
10-27-2004, 09:53 PM
While not a traditional means of handling the steering chores on an early rod, there's no inherent problem with running a properly engineered rack & pinion steering system in conjunction with a dropped tube axle.

In fact, if you scan the pages of STREET RODDER and other mags, you'll see that they offer a retrofit kit to replace the common Vega boxes used in so many rod applications with a compact rack and pinion unit designed specifically for use in rods with straight axle front suspensions.

Some may not like the way it looks, but I'd rather spend $350 for the new rack & pinion kit than to spend the same amount or MORE on a Vega box...hell, you can buy a whole VEGA for less than $350...minus the spit-shine on the steering box!

(And I know a little something about buying Vega parts! http://www.jalopyjournal.com/ubbthreads/images/graemlins/tongue.gif http://www.jalopyjournal.com/ubbthreads/images/graemlins/crazy.gif http://www.jalopyjournal.com/ubbthreads/images/graemlins/grin.gif)

metalshapes
10-27-2004, 09:54 PM
[ QUOTE ]

The only way I know of to not do bump steer with a rack and a solid axle (live axle?) is to mount the rack to the axle.

[/ QUOTE ]

Before you do that, please read the Thread I just talked about...

Edit,
Its called Trick steering spotted fake-out or not.
There is a lot of useless Drama on it, but also some info...
Ignore the whole bit about the gutted early Ford box, and concentrate on the R&P part, it will tell you what you need to know...

Wowcars
10-27-2004, 10:09 PM
I didn't see Metalshapes thread, but the best way I know how to do this is to mount the rack directly to the axle, so the geometry does not change from the axle to the steering when hitting bumps (thus causing said bump-steer) BUT you have to make sure that your steering has some sort of sleeve shaft in it to make up the difference on full travel of the front suspension and obviously does not fall apart on extreme bumps. Best when the sleeve is placed as the last joint before the rack. Plus, with this scenerio, you must use some sort of support bearing bolted solidly to the frame rail. OR: ditch it all and run a steering box!
Hope this helps.

Paul2748
10-27-2004, 10:20 PM
As was said, for the rack and pinion to work correctly it must be mounted to the axle. I had a rack on a Model A that was attached to the axle and it worked beautifully for the ten years I had the car. I used a GM collapsible "slider" for the link between the column and the rack.

ELpolacko
10-27-2004, 11:05 PM
Please read this if you think this is a good idea! Trick steering spotted or Fake out (http://www.jalopyjournal.com/ubbthreads/showflat.php?Cat=&Board=UBB1&Number=568225&Forum=U BB1&Words=fake%20steering&Match=Entire%20Phrase&Se archpage=13&Limit=25&Old=3months&Main=564222&Searc h=true#Post568225)

We have gone over this subject before. I can assure you if this was a good idea companies like FatMan and No Limmit would be all over it. BUT you will notice that no one makes a kit to do such a thing, because its a bad idea!

Like I said before, I just don't understand what everyones hard on is for rack and pinion steering. Whats wrong with a good steering box?

ratster
10-28-2004, 09:50 AM
Here 's a problem I have, I need to put power steering on my brothers "T" coupe that I have to build for him. The law requires him to have power steering and brakes. He's a quadriplegic and has to have it. What kind of steering would you guys use then? We are planing on a drop tube axle kit, like the one Speedway sells.

Rand Man
10-28-2004, 10:39 AM
I've heard the Toyota Pickup box is a hot set-up. Many replace F100 boxes with the power Toyota unit for side steer systems. For a cross-steer, power steering setup, the GM 605 box should work similar to a Vega. I donít have any other information on the Toyota box. Has anyone used it?

Kevin Lee
10-28-2004, 10:43 AM
Any power steering box would work I would think? Just look for the smallest one available or find a way to make a big one fit. Be sure to use the pump meant for that particular box. If you have extra money for the job maybe you could use a power steering box from a sprint car?...not sure about ratios and whatnot with those though - might not be much of an improvement over manual. No first hand experience, just throwing out ideas.

50adrod
03-03-2011, 06:43 AM
Please read this if you think this is a good idea! Trick steering spotted or Fake out (http://www.jalopyjournal.com/ubbthreads/showflat.php?Cat=&Board=UBB1&Number=568225&Forum=UBB1&Words=fake%20steering&Match=Entire%20Phrase&Searchpage=13&Limit=25&Old=3months&Main=564222&Search=true#Post568225)

We have gone over this subject before. I can assure you if this was a good idea companies like FatMan and No Limmit would be all over it. BUT you will notice that no one makes a kit to do such a thing, because its a bad idea!

Like I said before, I just don't understand what everyones hard on is for rack and pinion steering. Whats wrong with a good steering box?


I realize this thread is 7 years old but No Limit now does make a kit to do this. at least for the classic trucks http://nolimit.net/prodinfo.asp?number=PS-SA-

ELpolacko
03-03-2011, 07:18 AM
Yes, at the time I wrote that not one shop had picked up the idea. And to this day only No Limit has that I can recall.

I still don't like the concept of putting steering universals into this type of service.

pitman
03-03-2011, 07:49 AM
While not a traditional means of handling the steering chores on an early rod, there's no inherent problem with running a properly engineered rack & pinion steering system in conjunction with a dropped tube axle.
Did a thumbnail calc. on how many miles the '32 or earlier rods I've built or fab. contributed to...that use junkyard purchased racks. Two cars come to mind. Pete Goodman's '32 5-window ~50k, and my newest '31 w/only 3k. I've also used racks on Vair front ends that add 120k miles to this calc.
They've been a good alternative to a box. Make the mounts rugged (to the axle), position the rack for correct ackerman and clearance of neighboring components as the axle moves. Use a well made slip joint. The weight savings, lack of clearance problems...and road feel will work out if done right.