Should be a Formula unless someone swapped a V6 into a 4 cyl coupe.
Do you have the VIN? If not, you could ask them for that under the excuse that you want to do a carfax on it.
The VIN will tell you if it is a factory Formula because it will be coded as a 6 cyl. The 8th digit will be a "9" for a V6 (Example, 1G2PE1195JP000000
Edit: Indiana Resto Guy beat me to it this time!
2009 Volvo C30 T5
1988 Pontiac Fiero Formula T-top
1988 Pontiac Fiero Formula Hardtop
[This message has been edited by Fformula88 (edited 06-14-2010).]