UPDATE:
We’ve just gotten word from Steve Lycett under his S0L tag that the staff behind the ASR Facebook page have got the wrong end of the stick, there is in in fact no custom vehicle option in the game.

That Custom Vehicle comment is a cock-up by whoever does the Facebook page, I can absolutely confirm that the game doesn’t support that feature, you’ll be seeing that vanish shortly. I’ll let AAUK double confirm this.

Beleive me, it would be a cool feature, but it’d take us another two years to add it!

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S0L
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/END UPDATE

SEGA have revealed via the Sonic & SEGA All Stars Racing Facebook page that players will be able to make their own custom vehicles in the game but no details are revealed as to what extent you can customize or whether the feature is available on all five platforms.

We’ll update you when more information is made available.