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Rack or box less effort?

Posted: Fri Oct 09, 2020 9:20 am
by theKbStockpiler
Hi. Here's another one of those not so well known facts. If I'm parking and or driving around town, is a vdub with a Steering Gear actually easier to drive than one with a Rack?

Thanks for your expertise and experience!

Re: Rack or box less effort?

Posted: Fri Oct 09, 2020 9:45 am
by eskamobob1
Steering weight is far more down to geometry than type of steering movement. Also, worm gear and pinion size have massive effects on steering effort, so even with similar systems you can have big variations in weight with just that. Are you looking at 2 options specifically you would like a comparison between?

Re: Rack or box less effort?

Posted: Fri Oct 09, 2020 10:02 am
by Ol'fogasaurus
There are other things to consider also on the R&P such as center or off-set steering connection. A lot of the center steering R&P I have seen lately, and this was for the sand) also had electric steering conversion on the steering shaft. Other than weight I haven't seen or heard of any really bad talk about the conversion.

Lee

Re: Rack or box less effort?

Posted: Fri Oct 09, 2020 11:01 am
by theKbStockpiler
Let's go with 74 compared to a 75 super beetle. A stock rack verses a stock steering box.

Re: Rack or box less effort?

Posted: Fri Oct 09, 2020 7:10 pm
by Ol'fogasaurus
theKbStockpiler wrote: Fri Oct 09, 2020 11:01 am Let's go with 74 compared to a 75 super beetle. A stock rack verses a stock steering box.
After being castigated :roll: :lol: on my post I did a search to see what was going on with the different styles. There are at least three basic styles of steering:

The Rack and Pinion which has less moving parts, weight, better road feel, either left hand mounting, right hand mounting or center mounting and, with front engine cars, the room needed to get around things is less. The main drawback/complaint was it was not as self-centering as other types of steering.

Recirculating ball which is a hydraulic steering. No real opinions I found.

the old style of steering which also is call a worm gear style. Pretty strong and bulky but it is usually setup for either left side steering or right side steering.

What I couldn't find was anything on strength as I have heard of the R&P getting broken in odd situations.

Do an online search to see if you get more info as my search was a quick and dirty style of search.

Lee

Re: Rack or box less effort?

Posted: Sat Oct 10, 2020 11:57 pm
by 66brm
I've noticed the biggest change is with tyre pressures and tyre size/width, not the style of steering box

Re: Rack or box less effort?

Posted: Sun Oct 11, 2020 9:52 am
by Ol'fogasaurus
66brm wrote: Sat Oct 10, 2020 11:57 pm I've noticed the biggest change is with tyre pressures and tyre size/width, not the style of steering box
True but but add to that the type of tyre you are dealing with (radial vs. bias-ply), with all things considered, the R&P is usually a bit quicker of a steer but... I think I seem to remember, in backing up you might feel the pressure a bit more.

Lee

Re: Rack or box less effort?

Posted: Sun Oct 11, 2020 6:52 pm
by theKbStockpiler
The ratios compared would tell most of the story. I have read that the factory repair manuals have them listed.

Re: Rack or box less effort?

Posted: Thu Nov 26, 2020 10:30 am
by buildabiggerboxer
Theres nothing wrong with the steering box, other than they are often old and worn, with a super beetle fitting a rack will save you some weight by getting rid of the idler housing etc and the 'box is not as strong as as a BJ 'box, if fitting an after market rack fitting position is critical to avoid bump steer and bad handling or you may as well not bother. easyest way is to fit all the stock parts from the VW parts bin.

Re: Rack or box less effort?

Posted: Sat Nov 28, 2020 7:55 am
by eskamobob1
Eh. I largely agree that the stock box isn't bad, but with any kind of ball and sector box you will basicaly always have on center play while you can get this down to nearly naught with a good R&P. R&P supposedly also give better road texture, but if I had to guess, yoy could tune a box to be similar by playing with SAI, scrub, and a few other things if building from ground up.

The problem with this thread is OP has never clarified his actual question. If the question genuinely just is "on identical systems, what has more weight, R&P or worm and ball" the answer is just "whatever is worse quality will have slightly more weight due to higher internal friction, but steering weight is absalitely dominated by a number of other factors before what rack you have ever comes into play so don't worry about if you are thinking of swapping"

Re: Rack or box less effort?

Posted: Thu Dec 17, 2020 9:41 pm
by theKbStockpiler
eskamobob1 wrote: Sat Nov 28, 2020 7:55 am

The problem with this thread is OP has never clarified his actual question.
It's in the opening post. :wink:

For my own build I want a car that is easy to drive around town from 35-50mph. There's a few aspects that make this question opinionated. BMW; as far as I know,was the first car to have a rack but used a box the longest which seems strange. There must have been some reason for this.

In principle, I would prefer a rack but I have a 1302 so I don't know if a steering shaft is a bolt in and I also don't want to carve up the framehead and make it weak to put in a part that is as hard to source as what I would be replacing it with.

As far as scrub, with the 1302 having too much, wouldn't it be balanced out by the other side of the car as far as steering effort goes? One wheel would be forced against the on coming pavement and the other would be forced back by the pavement. With a bigger scrub radius, the wheel is moving as it scrubs so for the same amount of scrub through a turn ,it would be over a greater amount of pavement so it should take less force. This is the same principle that gives levers a Mechanical Advantage. Something I noticed with my 1302 is that while sitting still and turning the wheel , the wheels actually spin slightly while this is being done. Also I think vw deigned a lot of positive camber in the 1303's to reduce the scrub radius which causes Camber Thrust which can be bad, It seems to me that vw deliberately made the 1302 a specific way for a reason and it was not all because of cost.

Re: Rack or box less effort?

Posted: Mon Dec 21, 2020 11:55 am
by FJCamper
Short answer to a long question.

The average VW driver feels steering effort rise in proportion to tire width.

Steering boxes mechanically increased physical steering input which made most car makers to favor them. Rack and pinion had better dead-ahead feel and was cheaper (less complex) than steering boxes.

Of course that was back when engineering made sense. If you have some voo-doo power rack and pinion you are on your own.

FJC

Re: Rack or box less effort?

Posted: Mon Dec 21, 2020 6:07 pm
by theKbStockpiler
:?

Was it deemed better to have more physical strength to turn the wheel without modern caster or SAI? Was this pre caster SAI era?

Re: Rack or box less effort?

Posted: Mon Dec 21, 2020 7:10 pm
by Ol'fogasaurus
What is SAI ? Acronyms often have so many meanings with some of them end up being dirty :lol: .

Lee

Re: Rack or box less effort?

Posted: Tue Dec 22, 2020 7:24 am
by theKbStockpiler
In the context of steering:


caster SAI