kate205gti 4 Posted March 13, 2006 since fitting my mi16 box onto my BE1 205 i had been thinking the gearing was fantastic - 80mph at 3k and 95mph at 4k!! then i stuck satnav in my car my speedo is reading 90mph when im actually doing 75 the only thing ive changed is to put an mi16 box on (was 1.9) including the mi diff casing and quaife lsd what part controls the speedo reading please? and any idea how i fix it? ive still got the 1.9 box in bits in the workshop if i need to swap anything cheers Share this post Link to post Share on other sites
jackherer 543 Posted March 13, 2006 you can change the part the speedo cable goes into, but I think you have to pop a driveshaft out unfortunately. I had a gearbox that was like this, it was a 1.6 205 box so it really shouldnt have been any different to the box it replaced but the speedo was very ambitious which impressed people that hadnt been in many fast cars but got a bit tiring after a while. Share this post Link to post Share on other sites
Dino 3 Posted March 13, 2006 Kate I have the same problem albeit not quite as 'enthusiastic' as your reading. Mine reads about 10% more than it should. Would be interested to see what you do to fix this problem Share this post Link to post Share on other sites
Simes 248 2 Cars Posted March 13, 2006 Kate I have the same problem albeit not quite as 'enthusiastic' as your reading. Mine reads about 10% more than it should. Would be interested to see what you do to fix this problem Dino, most speedos read that much out. Share this post Link to post Share on other sites
pugrallye 0 Posted March 13, 2006 (edited) do 1.6 wheels have the same rolling radius as the 1.9's? If so, cannot see that changing the speedo drive will make any difference, as the gearing will be identical, clearly if the RR is different then the drive will be geared differently, and will need to pull off the N/S driveshaft to remove the brown plastic gear inside the housing Edited March 13, 2006 by pugrallye Share this post Link to post Share on other sites
kate205gti 4 Posted March 13, 2006 mine runs on 195/50/15 speedlines and always has so is not the tyres only thing thats changed is a rebuilt block and a different gearbox put in it used to be 5/6mph out which was fine and no problem - but it says im doing 80ish when im doing 70, 90 when im doing 75 and 115 when im doing 95, etc.. and is a bit off-putting! Share this post Link to post Share on other sites
C_W 3 1 Cars Posted March 13, 2006 My speedo overreads now since I change to a spare gearbox, the only thing I can think of is that there are different types of speedo assemblies at both the clocks and the gearbox end? Share this post Link to post Share on other sites
pugrallye 0 Posted March 13, 2006 (edited) oh sorry, my bad, read that wrong, okay did 405 mi'16s run on same size tyres as 1.9 gti's? I know the citroen BX 16v didnt, just thinking the speedo drive in your box is lower geared as its too far out to be a speedo prob, and differnece in varation increases with speed. Edited March 13, 2006 by pugrallye Share this post Link to post Share on other sites
littlemike 0 Posted March 13, 2006 Pull the speedo cable off the gearbox and it will have a plastic worm gear on the end of it (or it will stay in the gearbox, but you can then pull it out with your fingers). Swap it with the one out of your old gearbox + you will be sorted No need to touch driveshafts. There's a difference of two or three teeth between the 205 and 405mi worm gears which causes the speedo to over read using the 405 gear, but they're interchangeable. Share this post Link to post Share on other sites
jackherer 543 Posted March 13, 2006 the only thing I can think of is that there are different types of speedo assemblies at both the clocks and the gearbox end? yeah it has to be something like that, as I said above a 1.6 205 box I put in another 205 1.9 overread by about 25% and I swapped it for another 205 1.6 box which worked accurately, then eventually (for various reasons) I put the first box (the one that overread) back in but with the speedo drive from the second box and this worked fine. Share this post Link to post Share on other sites
kate205gti 4 Posted March 13, 2006 speedo drives def got to come out then im guessing - more gearbox oil lol have kept the old one though so hopefully should sort it will remember that for future!! Share this post Link to post Share on other sites
jackherer 543 Posted March 13, 2006 speedo drives def got to come out then im guessing - more gearbox oil lol well, if what littlemike says is true then no, you dont need to take the whole thing off and wont lose any oil. I swapped the entire speedo drive "assembly" because I didnt want to take it apart again if it didnt work, but it looks like I didnt need to Share this post Link to post Share on other sites
kate205gti 4 Posted March 13, 2006 ahh that sound even better - theres nothing worse than gearbox oil on a car! :sick: will take a look on sat Share this post Link to post Share on other sites