I bought last year a Seat Ibiza 1.6 8 valves with 75 donkeys. One of the previous owners seem to have put a shorter ratio gearbox, presumably from some VW Caddy o Seat Terra (I am in Spain, Seats are everywhere...) Now, the speedometer shows wrong valuesof course. I know that Volkswagen uses a different plastic shaft with a cog at its end to pick up the speed from the gearbox, and if I remember correctly they go with different colours. Is there a list of what shaft should go together with a gearbox? I dont know whats gearbox is under the car, this is the most unloved vehicle I ever owned... Where do I look? I am honestly tired to go on the motorway with other people and explain ever again the same story of the short ratio gearbox. Although I am going at 120 km/h the speedo marks 140, and the 3,800 rpm give the impression of a much higher speed. Moreover, considering that here everybody isnt ever in rush, most drive at 100 km/h: imagine, overtaking everybody with a car that marks 20 km/h more than the speed limit, at "just" 3800 rpms in 5th gear... Of course they ask! Thanks in advance!
look on the flat plate on the bottom of the gear housing, it sounds liek its a mk1 1.6 gti box possibly, if so you need a white gear oh and if your wheels are different rollign radius to factory standard that throws out the speedo, plus smallblock speedo is calibrated slightly differently to big block so another thing that can throw them out. if you look on the face theres a 4 digit code which tells you what calibration it is
Also if you get us the code, the diff FDR can be determined and the correct speedo drive can be recommended. For example, a ACD/AUG Golf MK2 gearbox has a red speedo gear with a 3.68 FD. Where as a 4.25 FDR runs a green speedo gear.
rubjonny, Thanks! Ill have a look now if I see anything. EDIT: no, the car is too low, today I am going to change the tyres and do the wheel alignment so Ill have a look better I dont think MK1 GTI though, simply because here there arent any around since ages, plus the previous owner said that the other previous owner put a gearbox from a Caddy or from a Terra. The car is now using 205/40-R17, which helps to make the ratio longer (and the braking distances too). I went for the MOT with a set of 185/60-R14 and the speed was even lower, but not that much. Indicated 140 Km/h, 118 on the satnav, while generally its 120. I now bought a set of 14" wheels because I needed to change the tyres and wanted to have more effective brakes. cerips, thanks for the link Ill have a look now. Thanks toyotec, you got me lost at FDR. Is it another code written somewhere?
once you know the gearbox code you can look it up in brokes ratio guide linked earlier, then compare the final drive fitted to the box to the speedo gear section a little further up on the same page
