I'm sure I see a 4th header pipe at the rear (to the left of the other pipes) of what I believe is a SBC engine. The 2 center pipes are closer together than the outer ones- typical siamesed center ports of the SBC. And the 292 number could represent a 283 Chevy bored .060" over, with the stock 3" stroke equals 291.87 or, 292 cu. in. That's my guess.