swiftr Posted January 18, 2005 Share Posted January 18, 2005 Thanks for the help so far but it's me again with another question! I have heard that for SVA the speedo transducer must be run off the rear wheels so that the test centre can confirm speedo accuracy on their rollers. I have the Smiths (white) clocks and the speedo for these runs off a hall effect device which senses the front offside hub nuts. Have I got a problem here, or am I OK as long as the speedo is accurate? Thanks, Richard Quote Link to comment Share on other sites More sharing options...
smithydar Posted January 18, 2005 Share Posted January 18, 2005 i dont know for sure but would have thought as long as it can be tested on the rollers .(can put wheels in rollers)you would be ok. but im really not too sure .might be worth a phone call to your sva test centre.better to be sure rather than fail. darren Quote Link to comment Share on other sites More sharing options...
darthurs Posted January 18, 2005 Share Posted January 18, 2005 I am not sure if they will be able to check your Speedo with it being on your front wheels. The two usual places that Westfield specify is using the bolts off your lobro joints or using the bolts for your propshaft as the sensors. Both of these will register a reading on the Speedo when on the rollers. With yours being on the front wheels I don't think they will rotate, therefore not give a reading. Worth checking though. Dan Quote Link to comment Share on other sites More sharing options...
Saltydog!! Posted January 18, 2005 Share Posted January 18, 2005 You should check with Mark at Westfield regarding SVA, although I can't see why it should be a problem. Surely they can put the front wheels on the rollers as easily as the rear. Are they not the same rollers that test the brakes?? The build manual certainly indicates that mounting on the front upright is the 'usual' option, giving the dip-switch settings for this location. I've just fitted the same clocks to mine, but opted to fit the sensor in the rear. I just had to get the correct dip-switch settings from the factory. I didn't like the idea of the cable running past the suspension and steering or the sensor bouncing around every time the wheel hits a bump. HTH, SD Quote Link to comment Share on other sites More sharing options...
pistonbroke Posted January 18, 2005 Share Posted January 18, 2005 I'm sure it has to be the "driven" wheels so the speedo can be tested at varios speeds Quote Link to comment Share on other sites More sharing options...
swiftr Posted January 18, 2005 Author Share Posted January 18, 2005 Thanks guys. Will check with Mark at Westfield. It was he who said to mount it at the front and supplied the wiring loom extension which runs from the speedo to the front wheel. Good point about this bouncing about more than the 'normal' transducer pointing at the lobro bolts! (Still have this and only taped the plug for this back into the wiring loom so can resurrect this route if needed! ). Cheers, Richard Quote Link to comment Share on other sites More sharing options...
zvezdochka Posted January 18, 2005 Share Posted January 18, 2005 I had the same advice from Mark, so mounted the sensor on the front hub. At SVA (Manchester) the inspector scratched his head as the rollers need to be driven by the car. (Low speed is only available to test front brakes) Fortunately I had checked the setting code on the Caerbont (Smiths) website and printed off the long list of numbers plus relevant extract from build manual. He was happy with this plus I said I had followed a car driven at 30mph and 40mph on a private road to check before SVA. Finally he drove it round car park. Test Cert read "Speedo could not be checked on roller but documentary evidence and inspector test confirmed acceptable". Suggest you are armed with calibration data if you stick with the front sensor. By the way first SVA failed on front/rear brake balance and foglight switch illumination. Brakes fixed with better front pads and switch rewired. Passed OK Sept 2003 Quote Link to comment Share on other sites More sharing options...
Barry Ashcroft Posted January 18, 2005 Share Posted January 18, 2005 I have the same transducer and did not want to fit i=on front wheel as the wire will be visable on the wishbones. What I did was take a hammer to the bracket at the rear of the chassis which is used for the vdo transducer bent it down nearer the lobro joints drilled a hole in the corner and fitted the small transducer there and positioned it over a lobro joint bolt. Did this also on my last car with no problems at all. Can take a picture if it helps. Barry Quote Link to comment Share on other sites More sharing options...
swiftr Posted January 18, 2005 Author Share Posted January 18, 2005 Thanks both for the further update. Do you know the website address for Caerbont so I can check calibration stuff? Barry, piccies would be useful and: a) did the wire from the transducer reach up to the back? b) presume the dip switch settings on the back of the speedo are different as there are 6 bolts on the lobro joint cf 4 on the front? The little things in life....... Still better to be forewarned rather than failing the SVA! Quote Link to comment Share on other sites More sharing options...
John Fisher Posted January 18, 2005 Share Posted January 18, 2005 I've just read through the SVA manual (speedometer section) and can't find anything in there regarding installation of the sensor to front or rear wheels. How do front wheel drive cars pass? - as far as I know all their speedo drives are from the front. For what it's worth I've fitted my sensor to the front, and will take advice Fish Quote Link to comment Share on other sites More sharing options...
Barry Ashcroft Posted January 18, 2005 Share Posted January 18, 2005 How do front wheel drive cars pass? - as far as I know all their speedo drives are from the front. Because there front wheels are DRIVEN Quote Link to comment Share on other sites More sharing options...
Barry Ashcroft Posted January 18, 2005 Share Posted January 18, 2005 a) did the wire from the transducer reach up to the back? b) presume the dip switch settings on the back of the speedo are different as there are 6 bolts on the lobro joint cf 4 on the front? Yes I gave mark my diff ratio and wheel size/rolling radius and he said what to set the dip switches to.Top bloke!!!! Quote Link to comment Share on other sites More sharing options...
John Fisher Posted January 19, 2005 Share Posted January 19, 2005 Realised what i had said regarding front wheel drive cars is bo*8l*ks , but I still can't find any reference to the transducer having to be fitted to driven wheels Fish Quote Link to comment Share on other sites More sharing options...
Saltydog!! Posted January 19, 2005 Share Posted January 19, 2005 Richard, Yes the wire does reach up to the back, just. I did the same as barry mounting mine. The wire runs along with the loom in the tunnel and up through the loom gromet under the dash. I JUST had enough length with a small loop next to the sensor, so if you go this route don't go the long way round!! If you want I can take a picture and e-mail to you. I can also give you the dip-switch settings if you have standard 15" wheels & tyres (195/50/15) 1 to 10 (off-off-on-on-off-on-off-off-off-on). HTH, SD Quote Link to comment Share on other sites More sharing options...
ciscobay Posted January 19, 2005 Share Posted January 19, 2005 I have the transducer on the front hub passed the sva at norwich in august they couldn't test the speedo calbration because it was not on the driven wheels. passed without testing not my fault they can't test it just drove it round the car park to check it worked. Quote Link to comment Share on other sites More sharing options...
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