does anyone know how i can get my speedo fixed i have 20inch rims on a vr statesman and when im doing 70 im really doing 60 the more speed i get the bigger the gap say 120 and im doing 90 to 95 where do i go to fix this
what size tyres you got? the biggest tyre you can go to is 245 30 20, which is only 1.8% bigger than standard which is the best tyre for the load rating, but the tyre to keep it perfect is 225 30 20 but you'l be popping tyres every day..
If your tyres are bigger diameter then your speedo will be reading under. 70 on the speedo is not 60, more like 80
i did have 35's on my car and the speedo was out by about 8k at 100, so i was reading about 92 on my speedo.. ive got a VT so my standard wheel size might be a little bigger then the VR but im not sure.. but what makes it worse is long gearing and the weak breaking
get the speedo re-calibrated. will cost anywhere between $100-$250. ive never seen rims throw a speedo out that bad before. you sure you didnt just install higher diff gears like 3.45's or 3.7's?
My 20's on my ute put me over by about 10% so at 100kph im doing 110kph. Same as my truck with 35" muddies its also out by a factor of 12% or so. I have no idea why your car is saying its a negative speed reading :/
I have 19's with low profiles on my VR statesman and my speedo is only out by a couple of K's. compare it with a GPS if you have one to see how far out you are. I think your speed alert should still read fine, so maybe set it at 100 and then take a drive down the highway, and take note at what speed the cluster reads when your alarm sounds.
Yeah sory, should make things more clear, 245 35 20... as apposed to 245 30 20, with the 30's its only out by 1.8k at 100. So when im reading 98.2 im at 100 to the original calibration. (which may have been 2k out the other way anyway..)?? Im kinda keen to get a set of 19's for every day tho as the 20's are just soo hard and unforgiving. every road feels like a camel track !! Anyway this thread aint about me, this guy still hasnt told us what tyres he's running..
yah i think you might be right with higher diff gears but diddnt know that throws ya speedo out aswell as my 20s i havnt had the car long and still finding things that have been done i have a cam , stage 2 shift kit , stainless steal extractors , and a redback sports system and now that you bought up the idea of higher diff gears i think that is the one. by the way that pic of your car is verrrrrrrrry nice.
20s have the same rolling height as 15, 17, wich ever it can alter slightly as some brand new tyres come with eg 15mm tread depth and others come with only 8mm, also in the profile series manufacturers are allowed a 10% window in the actual "ride height" so most chinese or low-mid range are the main ones for this. but 245 30 20s are the closest you will get unfortunately
