i bought some manual turbo clocks from pod in sunday tried fitting them and speedo is miles out thing is i thought they would work correct because i had an f28 box. I have heard about the speedo ring in the g box maybe courtenay fitted the f20 speedo ring when they did the conversion to suit the 140mph original clocks.?
Does any 1 know how i can get these clocks to read right in my car???
Maybe i could change speedo rings. does this involve splitting the whole box?
would it be possible to swap somthing in the clocks or have them re-calibrated or something?
Sounds to me like you definately have the F20 speedo ring fitted. In order to make the turbo clocks read corect you definately need both the turbo speedo ring and the drive gear (blue in colour). Both of these are unavailable from Vauxhall.
To change the speedo gear the box has to be split for the work to be carried out. I think some of the last Astra GSi's had 160mph clocks which run on the F20 ring, if you don't want the hassle of taking the box apart could be worth trying to get hold of one of these.