I bet quids it would not work. I think that the variables are too great to get the results that you need. The SU is not as simple as it seems.

This is the type of Transducer I had in mind;-

http://australia.rs-online.com/web/sear ... &R=0144507

Temp from -40 to +135
Shock to 15G......

What do you think Mick?

Again I must say "I know nothin" But this is what I had in mind..




I don't know what size these come in and I don't know if they can read
through 2mm of alloy.

Why would you want to do this anyway, the SU is already doing this without having to spend thousands of dollars to make something that is basically a mechanical low presure fuel injection system.

You would need to fit air flow and throttle postion sensors and a oxy sensor/lamda unit in the exhaust to determine if the needle is at the right height and don't forget the ECU to collect the data and interperate the info and control it, so you would be better of with a full fuel injection system than trying to modify a SU to become a metering unit.

Much easier to get the right needle and spring and not somuch to go wrong

Just my thoughts and people are all different

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Roundies and Clubbies(except vans) are both ugly that is why I have Midas and a van
1293 Mini Midas Bronze,1275 Clubman van

This is exactly what this discussion/idea is all about. Measuring data to determine just what characteristics the needle should have so the correct one can be fitted.

A tuning tool is what is being sought.

Steve

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1964 998cc Cooper
1971 Mini K x 2
1972 Clubman GT

I already have an SU that is hooked up to a computer.
Austin did that in the 80s.

Alreay exists its called a dyno, the cost of this unit you speak of is far greater than a few hours of dyno time and to obtain true data the vehicle must be put under load to get true readings so either it goes on a dyno or the car must be driven to obtain the real data andf as i said the cost is prohibitive, but if you think its not go ahead its not my money

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Roundies and Clubbies(except vans) are both ugly that is why I have Midas and a van
1293 Mini Midas Bronze,1275 Clubman van

This is a realy great discussion, one I have been watching quitely.

I agree with feralsprint in that the intial cost would probably out weigh the cost of a dyno session,,, however,, if you had to do a few vehicles, perhaps a removable system for collecting data while driving could be cheaper than a trip to the dyno tuners each time you build a motor?

Typically, if I need to leave a car at my dyno guy for 3 days (there is usually a few people infront of me and it probably takes them a day to work nut it out) it costs me about $1200.00....... small price to pay I reckon for the benifits of a well set up motor....

so if I were to add up one payment of $1200 for such a device that could do an on road data collection v's 8 X $1200 to do all my cars,,, it would work out cheaper in the long run.... (and obviously cheaper than the out right purchse of a dyno)....

So I'm still sitting on the fence waiting to see where this goes...

just my 2cents.

I was only clarifying what others were wanting to do. No skin off my nose if it costs a lot.

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1964 998cc Cooper
1971 Mini K x 2
1972 Clubman GT

Don't discount the DIY factor either.. I'd happily spend $$ and hours setting something up to log data to a laptop, just for the challenge

Partly the reason I'll put an EDIS/Megajolt kit together on one of my cars.. not because I need to, but because I can -- and then I can fiddle with it

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Simon

The adventures of an owner builder in the Tallarook Ranges

I'll look into them, but I'm still a little shaky on them being useful. Magnetic fields are really (really really) non-linear in their fields, weak without a strong current or magnet, and are also really heavily seduced by what's about them (ignition systems) when they are sensitive enough....so its a little difficult to work out without a play...and the response might be anything but linear for a known movement of the piston.

I'll take a look at linear transducers and also the infra red device I looked at earlier as well. It doesn't need to be expensive. The sensor will be the crux. If its something simple it can be fed directly onto the analogue to digital port of a cheap/small micro.

Its not that difficult a question, not a lot of money ( maybe tax deductible ) and could be a little interesting. I'll check it out over the next few days...

MG Rocketm could you measure for me the total displacement of the piston from bottom to top of the damper? I've got plenty of 1.25s around here but not sure what you are using. It will change the sensor that can be used..

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SooperDooperMiniCooperExpertEngineering

All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.

I would agree in principal here with feralsprint, however good chassis dyno people are not always easy to find and if your doing a bit of 'R & D' trying different things, going to the dyno guy can became costly and drawn out. If you've only the one car to do with no further mods, then it maybe costly to go the DIY route.

HI

if you have a look at my article on Project Small Bore you'll see my gizmo that i use and it's marked off with 1/8 lines so you can see exactly
where your needle is working, it's a little hard to use on the road,
but if you give your girl friend/ wife a light and put them under the bonnet
so they can see in the dark your right, i'm trying to train possoms they dont need a light, there's plenty of them at my place
Graham Russell

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"It's better to be not informed than ill-informed"

HI
Sorry i for got to say what use is it to know where your needle is if you dont have an air fuel meter to let you know what mixture your running.
Graham Russell

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"It's better to be not informed than ill-informed"

Hmmmm.......possoms eh??? Now I know what the family of them is doing living in my workshop.....................