A 1978 Sport Coupe what? You didn't say what the model is which will be helpful in determining a price. You can find some general pricing guides on the following websites [url]www.collectorcarmarket.com[/url] [url]www.nadaguides.com[/url] OR you could just search online classifed ads to price compare other vehicles to yours. Either way, it's only worth what someone will pay for it.