Martian
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| posted on 17/4/08 at 11:42 AM |
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quicker steering
hi everybody, i am after quickening the steering on my locost and, being very tight, wants to do it cheap! someone has suggested drilling a new hole
in the steering arm (sierra hubs). this will shorten the arm, i think it's strong enough. if the arm is shortened by, say, a third, will it
reduce lock to lock by a third? or is this all a bad idea?
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Martian
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| posted on 17/4/08 at 12:11 PM |
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same lock, less movement on steering wheel.....yes? main reason i've posted on here, i expect some one to shout ' bad idea', spend
money on quick rack!! the idea seems o.k. but there might be something i'm missing!
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DarrenW
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| posted on 17/4/08 at 12:16 PM |
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afaik the only way to quicken the steering is to change the gearing ratio between rack and pinion.
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blakep82
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| posted on 17/4/08 at 12:18 PM |
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it won't alter the number of turn lock to lock on the wheel, but it will give more movement of the road wheels, so i guess it will speed the
steering up a little bit (if it takes you 10 seconds to turn lock to lock and the road wheels to turn through 80deg for example, after a redrill the
arms, you might get 90 degrees. so if you turn the steering wheel through the same 10 seconds, your wheels turn 90 degrees, then yes it'll be
quicker.
but i'd go for a quick rack. they're only about £100 for a whole rack, or you can get the internals and do it yourself.
________________________
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02GF74
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| posted on 17/4/08 at 12:26 PM |
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new hole in steering arm?
You really think that is safe? 
By all means do it if you are willing to die or be severely injured for the sake of £ 70.
IMO you don't f**K around with brakes or steering.
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Howlor
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| posted on 17/4/08 at 12:27 PM |
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I may be been a bit thick here but I think it will alter the number of turns lock to lock as the steering rack will have to move less for the wheel to
reach full rotation about the ball joints.
Steve
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Mr Whippy
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| posted on 17/4/08 at 12:29 PM |
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not too keen on that idea and are you sure you have enough metal where you want to drill. Mind though if you do move it that the rack will have to
move also otherwise the steering will be wonky (to use the technical term)
Fame is when your old car is plastered all over the internet
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blakep82
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| posted on 17/4/08 at 12:30 PM |
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quote:
Originally posted by Howlor
I may be been a bit thick here but I think it will alter the number of turns lock to lock as the steering rack will have to move less for the wheel to
reach full rotation about the ball joints.
Steve
but the full lock it limited by the ends of the rack itself. the ball joints would spin through 360 degrees (well, infinitely) if chassis and
suspension wasn't in the way
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Howlor
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| posted on 17/4/08 at 12:37 PM |
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I agree but the fact that the wheels are limited means that the number of turns lock to lock will reduce.
Steve
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blakep82
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| posted on 17/4/08 at 12:43 PM |
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but the full steering lock isn't limited by the wheels hitting your wishbones/chassis (or at least it shouldn't be, otherwise thats an sva
fail)
its limited by the rack
________________________
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MikeRJ
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| posted on 17/4/08 at 12:48 PM |
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quote:
Originally posted by Howlor
I agree but the fact that the wheels are limited means that the number of turns lock to lock will reduce.
Steve
This would only be the case if the wheels fouled on the bodywork before the rack reached it's limits. Ignoring this, shorter steering arms
will speed up the steering, but the number of turns lock-lock will be the same, you just get more lock.
Note also that this is likely to have some impact on bump steer (may improve it or make it worse depending on geometry).
Martian, are the steering arms the same thickness along their entire length, or do they have extra metal around the hole for the TRE? How are you
going to get the correct tapered hole for the TREs?
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Bluemoon
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| posted on 17/4/08 at 12:50 PM |
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I would get a quick rack.. You could move the pivots if you limit the rack travel, but the following might be a problem:
1) Not enough strength in casting.
2) More strain on ball joints.
3) Steering Geometry altered.
Without knowing how 1 to 3 are effected by the mod I would agree with the probably better not do that camp..
Dan
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MustangSix
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| posted on 17/4/08 at 12:51 PM |
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Not entirely sure what SVA looks for, but using the rack limit as a steering stop is a bad idea. There should be a mechanical stop on the spindle
itself to limit its travel. Very common on most cars.
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Martian
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| posted on 17/4/08 at 01:15 PM |
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thanks guys! there is enough metal on the arms, but obviously the holes would need drilling with a tapered drill (i wasn't going to do it
myself) and it would need some sort of lock stop on the rack. after reading your views, i'll get a quick rack
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blakep82
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| posted on 17/4/08 at 01:16 PM |
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quote:
Originally posted by Martian
i'll get a quick rack
good choice 
________________________
IVA manual link http://www.businesslink.gov.uk/bdotg/action/detail?type=RESOURCES&itemId=1081997083
don't write OT on a new thread title, you're creating the topic, everything you write is very much ON topic!
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MikeRJ
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| posted on 17/4/08 at 02:12 PM |
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quote:
Originally posted by MustangSix
Not entirely sure what SVA looks for, but using the rack limit as a steering stop is a bad idea. There should be a mechanical stop on the spindle
itself to limit its travel. Very common on most cars.
On some cars perhaps, but I don't think I've ever had a car that didn't use the rack to limit steering lock. Why is it a bad idea?
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Mr Whippy
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| posted on 17/4/08 at 02:22 PM |
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Some cars do have adjustable limit bolts on the uprights like my Nissan and all cars fitted with steering boxes have them but there is no reason to
fit them on a rack equipped car unless you have clearance issues. The car will only be on full lock at low speeds so the loading on the rack pinion
will be minimal.
Fame is when your old car is plastered all over the internet
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blakep82
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| posted on 17/4/08 at 02:34 PM |
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you're not supposed to hold power steering racks on full lock for more than a few seconds, but thats it...
________________________
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don't write OT on a new thread title, you're creating the topic, everything you write is very much ON topic!
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Mr Whippy
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| posted on 17/4/08 at 02:47 PM |
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I thought the pressure relief valve would just open and bypass the flow to the reservoir, you can hear the valve whine like my digger does at full
travel with the arm.
Fame is when your old car is plastered all over the internet
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blakep82
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| posted on 17/4/08 at 02:48 PM |
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^ probably. its just what i read in one of my cars handbooks at some time.
________________________
IVA manual link http://www.businesslink.gov.uk/bdotg/action/detail?type=RESOURCES&itemId=1081997083
don't write OT on a new thread title, you're creating the topic, everything you write is very much ON topic!
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snapper
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| posted on 17/4/08 at 05:27 PM |
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Cheapest quick(er) rack if it is a Sierra rack is to use the Sierra power steering one with some fluid in the pipes and the pipes joined together,
stops the moving parts seezing up
I eat to survive
I drink to forget
I breath to pi55 my ex wife off (and now my ex partner)
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MustangSix
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| posted on 17/4/08 at 06:21 PM |
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Using the steering rack as a limit has a couple of potential drawbacks.
First, many racks only have a snap ring to limit rack travel. That is not a very sturdy stop.
Second, if the rack should fail at that point, there is the potential for the spindle to overtravel. That potentially sets up conditions for an
overcenter which would not allow a return, fouling of bodywork, or potentially even tearing off the brake lines.
Third, even once the stops are reached, the effect is then transferred to the rack mounts. With rubber mounts, that means you have rubber stops. The
mount would have to be designed to withstand that type of lateral stress.
It is definitely doable, but bear in mind the possible issues.
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bracey
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| posted on 17/4/08 at 06:49 PM |
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what is preffered number of turns for a 7 style car lock to lock for best results ,feel and drive
cheers
richard
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