Speedo error

rhanagar

rhanagar

Well-Known Forum User
As some of you might know I have just done an engine gearbox swap from a n/a auto to a turbo manual. I had to put the speedo drive from the donor car into the new one and found that the actual speedometer display is way out. It seems to be doubling up the displayed value from the actual value. Is there an easy way of rectifying this or is it quite involved. I cannot put the drive from the autobox in as the entire thing is different i.e. spindle and the way it is held. I am assuming some clever wiring involving resistors and stuff which I know little about is involved.

Cheers

Neal
 
Yep, both cars read the speed fine before the swap. Both in MPH. The only other complication I can see is that the gearbox and turbo engine came from a pre-facelift model, and put into a facelift model. I am using the n/a autobox ECU as well as the turbo ECU is causing issues.
 
If you have or can borrow a sat nav then you can calibrate the speedo to exactly how much its out. If it proves to be as already suggested as much as KPH to MPH then you will have to buy a converter> i am not sure but you might be able to get an adjustable electronic converter? the idea sounds easy enough. Or the other alternative is to remove the clear plastic cover and move the needle to the correst speed again using the sat nav. I hope this helps. I did my adjustment this way when I changed the faces and fooked up the calibration.
 
That is an idea. I have a Sat Nav which displays the speed. I know it isn't the most accurate of things but it does give a fairly good idea, better than the speedo anyway. Mind you if you go by the dial at the mo it seems that I can reach 140 MPH in around 9 seconds. God these cars are fast.......:)
 
Hi mate
As you know I did the same conversion and got round the speedo problem by swapping the cog from the sender out of the auto box with the one from the manual. This involves knocking out a retaining pin in the side of the unit, now i come to think of it I may have changed the whole insides over. Start by removing the pin (I used a nail and hammer) then withdraw the internals and swap em over. My speedo reads as good as it ever has done so problem solved.
Cheers

Mick
 
Sorry for the delay but been having computer problems. The differential is the original autobox one. The Differential on the manual turbo car had more iron filings in the bottom than was healthy. I Know that this has a difference on the final speed but I had no choice. Does anyone know what the diffenrence would be.
 
You must log in or register to reply here.
Back
Top