I ran a set of t/a heads with w2rockers on a pump gas 340 for about 10 years made 339 hp @ rear wheel.with a 557 cam.best of 7.17 same short block with la heads and a 508 hydralic had best of 8.38. built same short block again with econo heads best 7.09 . I sold the first 340 with the t/a heads for$2500 without oil pan . that should give a idea of worth.probably worth more if no porting work has been done.