@flu I mentioned the Pontiac GTO because it is an older vehicle, has full independent suspension, has options for manual transmission (the G8 is mostly automatic), uses a Chevy LSx based engine (when means you can be street legal and if you have spare cash, go nuts with an LS9, or sort of nuts with an LSA). Just get the engine from a vehicle of the same year or newer and you are emissions legal – and have horsepower of nearly 600hp for LSA and near 700hp for LS9. There are also a lot of aftermarket parts for the vehicle, and if you don’t find them in the US, you can find them from Australia (It is a Holden chassis). It is heavier than 3000lbs, but that helps if you get hit. A ‘tap’ by someone pushing cars around on the track is less likely to kick you off your line.
What type of vehicles are your beaters? You didn’t mention whether you are doing class racing, and have restrictions on the mods you can do.