17x8 +40ish and something like a 215/45/17 tyre or 17x7 +40ish with about the same tyre
the closest you will get for best speedo accuracy is the VRX size of 195/55 R16, this will give you a reading of 95.91 kph at an actual 100 kph.
I think wagonmaster's calculation was based on the current 195/55/R15 (stock) sitting on a perfect 100km/h, if the true reading on the stockies is 96kmph then you could safely run 205/50/16 which will bring your speedo up 3% so should read 100kmph when actual speed is 98-99kmph. Same with 205/45/R17 should read about 98-99kmph if your current reading from the stockies is as you say, 95-96kmph.Yeah I have the stock 195 / 55 R15
The reason I'm looking at the 205's is because they're a lot cheaper than other sizes, for the specific tyre I want anyway, and I'd prefer the thicker rubber compared to the 17"'s. Also the 205's only have a diameter 11mm bigger than the stock VRX so I can't imagine they'd cause a problem scrubbing wise at least?
This I'm a bit confused about because when I compare my speedo to the GPS on my 15 inch wheels, the GPS tells me I'm doing 95km/h - 96km/h when my speedo is right on 100km/h, so how is it the VRX is the same if it uses 16 inch wheels?
You have 2 options which will equate to solving all your issues.
1. Buy the correct tyre size to retain speedo accuracy, deal with the tyre cost or look at another tyre option.
2. Buy the larger tyre for cheaper and have an incorrect speedo, and then buy a speed correction kit and spend x amount of time trying to get that to work.
I would do #1. What tyre are you looking at?