change of tyre profile

need some tyres for the foz but they have 215 55 17s on and cost stupid money compared to 45 profile if i was to go with 45 profile would that knock clocks out by much (mph) and would i need to get g-om set up again i understand she is sitting on wrx springs/shocks

any advice welcome

Hi Andy,
Mine is running 215/45/17's and it only put the speedo out by about 3mph.

You will not need any change in the alignment - cannot help checking though.

cheers bud just toying with the idea at mo as will be cheeper in long run

Specification Sidewall Radius Diameter Circumference Revs/km Difference
225/55-17 124mm 340mm 679mm 2134mm 469 0.0%
225/45-17 101mm 317mm 634mm 1993mm 502 -6.6%

So when your speedo reads 60mph you will be doing 56mph

cheers bud thanks for the help