Thanks raceur. That's not the problem. I was more trying figure the issue with the Aston event. Unfortunately looks like it's a ghost event.
There's 17 of varying difficulty from C to S class (IMHO).
http://www.gamefaqs.com/ps3/942026-gran-turismo-5-prologue/faqs/56822
DEALERSHIP EVENTS
__________________________________________________________________________
These events aren't numbered in the game but I did so below and in the
walkthrough for the sake of conveniency.
D-1 Alfa Romeo Brera One-Make race.
This is a one-make race for the Brera Skywindow 3.2 JTS Q4, on
Daytona Course.
D-2 Audi TT Coupe 3.2 Quattro One-Make race
This is a one-make race for the Audi TT Coupe 3.2 Quattro held on
Suzuka Circuit.
D-3 BMW 135i Coupe One-Make race
This one-make race for the BMW 135i Coupe is held on the High Speed
Ring reverse course.
D-4 Chevrolet Corvette Z06 One-Make race
This one-make race for the Chevrolet Corvette Z06 (C6) takes place on
the High Speed Ring.
D-5 Daihatsu Copen One-Make race
This one-make race for the Copen Active Top is held on the Suzuka
East Short Course.
D-6 Ferrari festival!
This Ferrari-only event is on Suzuka Circuit. F430, 599, F40, 512BB,
Ferrari California models are permitted.
D-7 Ford GT One-Make race
This is a one-make race for the Ford GT on the High Speed Ring.
D-8 Honda Integra Type R One-Make race
This is a one-make race for the Integra Type R (DC5), on the Daytona
Oval.
D-9 Lotus Elise 111R One-Make race
This is a one-make race for the Elise 111R held on the London course.
D-10 Mazda RX-7 Spirit R Type A One-Make race
This is a one-make race for the Mazda RX-7 Spirit R Type A (FD) '02
on Daytona road course.
D-11 Mercedes-Benz SL 55 AMG One-Make race
This is a one-make race for the Mercedes SL 55 AMG (R230) on the
Suzuka Circuit.
D-12 Mini Cooper S One-Make race
This is a one-make race for the Mini Cooper S, taking place on the
London course.
D-13 Nissan GT-R One-Make race
This one-make race is using the Nissan GT-R, taking place on Fuji
Speedway F course.
D-14 Renault Clio Sport V6 24V One-Make race
This race for the Renault Clio Sport V6 24V is held on the Suzuka
East course.
D-15 Suzuki Swift Sports one-Make race
This is a one-make race for the Suzuki Swift Sport, held on the Eiger
Nordwand course.
D-16 TVR Tuscan and Tamora meeting
This is a race specifically for the Tuscan Speed 6 and Tamora, on
Suzuka Circuit.
D-17 Volkswagen Golf V GTi One-Make race
This one-make race for the VW Golf V GTI takes place on the Fuji
Speedway GT course.