the race base model has exactly the same engine like all other ek9s
the only diference was the interior,extras and rims.
have in mind that the race base was cheaper in japan than the ek4.(i know plp they paid more for a race base than for a normal)
the only extra the race base model had was the Power-steering the models with PS weighted 1050kg vs 1040kg the ones without PS ,the full ek9 was 1090kg
if an ek9 has SRS,ABS,air condition or electric windows is not race base.
i dont see any reason to buy a racebase when the prices are similar to the normal ek9 ,if you want you can strip it by yourself and sell the extra parts.