I've just installed a 4.6 ring gear in my diff and the speedo is now reading a lot higher than it should I know there is the yellowjacket but they are usually send from the US. Does anyone know of a UK supplier or UK equivalent?

 

I just ordered a yellow jacket last week if you order with the normal postage via usps you should avoid tax plus its quicker as it seems to sail through customs. I went to fit it last weekend and soon realised that our wiring is different to the US cars.

I found a thread on here where others have fitted it to uk spec cars, I followed the steps but it just doesn't work as I get "0" on the speedo, I don't know if mine is faulty but initially I was getting the correct test sequence but then it just drops power and doesn't work on the move, and sometimes the test sequence doesn't fire. I got my tuner to test the unit on their bench and the voltage output through the unit seems very low which maybe why it doesn't work. It's not a complicated unit really and there's not much to get wrong with the wiring it's just a 5v in ground out and tap into the vss, but I just couldn't get it to work.

I contacted Modifry about it and they said that they don't have a uk guide and best to look on the forum.

In the end I got annoyed with it and pulled the wires out and is ready to go in the bin.

I've found a place in Castle donington called NCS that use a box called speedm8 and they calibrate it for you, admittedly its quite a bit more expensive but is in the UK and they fit and calibrate it for you. I'm booked in on the 8th May to get one fitted so will let you know how I get on.

 

I've a yellow box one, not sure how pricing is as i got it with another S2000 and im waiting to put my FD into something to reinstall but it worked fine. Also in US it seems.

 

Ok thought I'd give an update on this.

Just got back from NCS and they fitted and calibrated my speedo on the road with a GPS unit, it is absolutely bang on now. At least now I know what speed I'm doing on the road.

 

MB has a yellowjacket installed; works fine in his S

 

He has a yellow box and his car is a facelift.

And maybe mine was a duff one. But since I didn't get any help from here or modifry and the device was tested on a bench and didn't seem to have enough current to convert the signal I decided to go a different route with UK support which worked.