magsy
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| posted on 2/5/06 at 12:23 AM |
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Power Steering?
Bear with me..
Been thinking about a RT+, saw the cars at the show this weekend and it looks good.
The thing is my old man would be helping with the build and will be expecting to drive it at the end. He had a bike shunt a while ago and is now arm
down.
We can work around the gearchange issues (BEC) but power steering is going to be a must.
Is this going to be possible somehow on the RT+?
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jollygreengiant
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| posted on 2/5/06 at 02:12 AM |
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Use something like the steering column out of the MG-F ( I believe & if I'm wrong then I appologise ) this has electrically assisted power
steering operating along the column rather than on the rack.
Beware of the Goldfish in the tulip mines. The ONLY defence against them is smoking peanut butter sandwiches.
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nitram38
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| posted on 2/5/06 at 03:52 AM |
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Some other rovers do electric assist on the column too. Just do a search on ebay, I have seen some on there.
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chockymonster
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| posted on 2/5/06 at 05:11 AM |
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Good choice of car, their customer service is fantastic too!.
The MGF option sounds sensible as I would have thought it was then possible to disable it.
Did you mention it to Marc at MNR? I'm sure he could come up with some ideas!
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Fatgadget
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| posted on 2/5/06 at 06:16 AM |
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Tha Vauxhall Corsa appears to be the favoured leccy power column with the Escort
brigade.Some info here
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Howlor
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| posted on 2/5/06 at 06:22 AM |
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Definately the Corsa option. Most of the rally guys now use this and the odd grasser. Easy to incorporate and small. there is plenty of space on the
MNR to fit this, all you will need is t oget mark to adapt the steerign column bracket.
Steve
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britishtrident
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| posted on 2/5/06 at 06:56 AM |
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Both the Corsa and MGTF have/had electric pas .
However keep the front tyres narrow and he should get on fine without power steering.
The big problem will be lack of self centreing
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smart51
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| posted on 2/5/06 at 07:04 AM |
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I work for an electric steering company. EPS is a good product. Ours certainly wouldn't fit in a vortx without a lot of work. I doubt that
competitor's products are smaller.
EPS systems are tuned to suit the car that it was designed for. The chances are that the tune wouldn't be ideal for a light weight car. My
vortx, with a quickrack, is only heavy at 2 or 3 MPH. At speed it gets quite light. Without a quick rack it would be lighter. See if you can get a
drive in one before deciding. Also, Marc is very helpful. Talk to him about it.
Even our smallest systems have a 70A fuse. You wouldn't get away with using a bike battery.
[Edited on 2-5-2006 by smart51]
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Ketchup
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| posted on 2/5/06 at 12:00 PM |
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lots of the fiat punto's have the electrically assisted power steering in the column.. its a really small unit and they come with quite a nice
little collapsable section with a uj on both ends.. the last time i replaced one it was about £150 new from fiat, must be a few in local scrapyards
tho, they have been about for a while
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Agriv8
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| posted on 2/5/06 at 01:05 PM |
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magsy,
Though the PAS sterring is an option and I am sure marc will be more than happy to go through the options.
Another option is how large is your dad. The MNR cars can have the Quick release wheels fitted . Thinking that
Possibly thinking along the lines of 2 Stering wheels one for yourself and a larger one for your dad swap and change as required.
My V8 ( 205 Rubber ) is probably the heaviest Vortex and I dont find it heavy on a small sterring wheel ( I am a largish chap ) .
I think as mentioned we can get arround it the best thing is have a word with Marc and get up to the Workshop for a chat and a cuppa and we will see
what can be sorted out let me know when you are going and I will try and make it over with mine.
Another point is to remeber that even though your dad may require PAS on a tin top - the need may not be there on a Kit car they are very light.
Regards
Agriv8
Taller than your average Guy !
Management is like a tree of monkeys. - Those at the top look down and see a tree full of smiling faces. BUT Those at the bottom look up and see a
tree full of a*seholes .............
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DarrenW
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| posted on 3/5/06 at 08:07 AM |
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quote:
Originally posted by smart51
I work for an electric steering company. EPS is a good product. Ours certainly wouldn't fit in a vortx without a lot of work. I doubt that
competitor's products are smaller.
EPS systems are tuned to suit the car that it was designed for. The chances are that the tune wouldn't be ideal for a light weight car. My
vortx, with a quickrack, is only heavy at 2 or 3 MPH. At speed it gets quite light. Without a quick rack it would be lighter. See if you can get a
drive in one before deciding. Also, Marc is very helpful. Talk to him about it.
Even our smallest systems have a 70A fuse. You wouldn't get away with using a bike battery.
[Edited on 2-5-2006 by smart51]
Who do you work for? TRW by any chance (Holford or Shirley?) I was working on the Gen2 project for a while and will hopefully be doing some bearing
work for Gen2.5 in the not too distant future.
I was under the impression that EPS was a very technical animal that required accurate ECU control. The software being tuned for particular vehicles.
Is it possible to retrofit eg a modus system into a kit car and get it running?
I have seen EPS powered cars with a city button (girly button) and a motorway setting. Is this done via the ECU?
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smart51
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| posted on 4/5/06 at 09:47 AM |
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quote:
Originally posted by DarrenW
Who do you work for? TRW by any chance ?
Yes, I work for TRW. The girly button is a Fiat thing and both our steering for the Stilo and Idea and another system for the Punto have it. It goes
to the ECU and changes the tune so that the steering is more "girly".
The tune is made to suit the target vehicle. It is designed to be stable under all conditions with good steering feel. As such, it takes accound of
the steering rack ratio and the steering geometry of the target vehicle. It might make a transplant into another car a bit unpredictable, especially
if the new car is lighter at the front.
As for a transplant into a seven, you wouldn't have the CAN bus of the donor car. The EPS would be unhappy without the vehcile speed signal,
for instance.
EPS is great, when done properly. I don't know is a simple transplant would be all that good.
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DarrenW
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| posted on 5/5/06 at 10:38 AM |
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Thats a good summary. i too was concerned that EPS would not be a simple transplant.
To be honest i think i would try and do the twin steering wheel idea as suggested. I use a 13" wheel and steering is quite light. Id be tempted
to build the car with std steering and get you father to try it with std Sierra wheel or if you want to test first see if the Nordons can let you test
drive with a larger wheel and a small wheel for direct comparison. It could take a lot of hassle out of the build. Failing that std hydraulic may be
the way to go but it will be extremely light and could lose feel in such a light car.
Thinking further all of the discussion above are for EPS (pure electric), there is also a EPHS option but again this is ECU controlled (basically an
electric motor powers the hydraulic pump instead of the engine).
Maybe a BEC with larger wheel would be lighter still.
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coozer
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| posted on 7/5/06 at 11:19 AM |
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The company I work for manufacters the Corsa column. I know a fair bit about them and I think to fit one to a locost would be quite simple.
All the assist is controlled in the supplied ecu with the output being dependent on the input. Cant see the weight of the vehicle having much of an
effect.
The more you put in combined with the load on the wheels the more it gives out. Simple.
All it needs to work is a signal from the engine, eg alternator.
External boxes are only needed if you want to adjust the settings.
It comes in tilt or non tilt, right or left. Although we only make the left hand version I think it will not be a problem for custom instalation.
Almost forgot, we also make all the eps columns for the Toyota Corrolla! Now, that is a neat column with an extension shaft equipped with
uj's. Does need the ecu though and thats seperate to the column, unlike teh Opel varietry.
[Edited on 7/5/06 by coozer]
1972 V8 Jago
1980 Z750
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RoadkillUK
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| posted on 7/5/06 at 12:48 PM |
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I was driving my locost yesterday and noticed how light the steering was, I'd say that the steering is no heavier than my PAS Xantia.
Roadkill - Lee
www.bradford7.co.uk
Latest Picture (14 Sept 2014)
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smart51
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| posted on 7/5/06 at 03:30 PM |
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So the EPS in a corsa is not vehicle speed sensitive then? Still, I guess it works well enough.
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coozer
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| posted on 7/5/06 at 08:55 PM |
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The steering is sensitive to how much effort goes into the wheel. When you are parked the resistance from the road is greater therefore you put more
effort into the wheel. Then when honking along the M1 at 70mph there is little resistance from the front and the eps doesnt give any assist because
theres little effort going into the steering wheel.
In the middle of the column there is a torsion bar that twists when an input is applied, the twist is measured by a potentiometer and the more input,
the more twist which = more output assist.
The column needs 12V and a signal to tell it the car is on! We replicate that with a signal generator when we bench test them. It's a particular
fequency that escapes me at the moment but I'm sure its the kind of signal your alternator kicks out. I will check when I go back to work.
PS. anybody want one?? 
[Edited on 7/5/06 by coozer]
1972 V8 Jago
1980 Z750
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marc n
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| posted on 10/5/06 at 07:17 AM |
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dont have any personal experiance with electric power steering but have heard of people fitting the corsa ones to rally cars and it working ok, think
i have a corsa one here with ecu somewhere will have to have a look , from what i remneber it was a small motor on the column shaft
best regards
marc
please email rather than u2u
direct workshop email ( manned 8am till 6pm )
www.mnrltd.co.uk enquireys to :-
chrismnrltd@btinternet.com
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NOTE:This user is registered as a LocostBuilders trader and may offer commercial services to other users
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coozer
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| posted on 10/5/06 at 10:08 PM |
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Checked with the designer and the Corsa column does have a spped sensor. It tells the column what speed teh car is going at and selects a different
torque map for the motor. Basically the faster you go the weaker the map (if you get my drift) and the assist drops off the faster you go.
It still works Ok though if you dont connect the sensoras it just stays on the default (lowest) map.
I see in this months Classic Ford mag there is a company offering conversions for Mk1 + 2 Escorts for £850! What a rip off, we sell them to Opel brand
new for £95!!! And we make a profit on that!
1972 V8 Jago
1980 Z750
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