The car will start and idle fine run up to 3500 rpm when the secondaries should kick and boggs any ideas ? Before switch over to su carbs iwanted to try to get these going . I tried unscrewing and cleaning out the jets no help

thanks it is a 73' l24 240z

thanks

After a ton of part swapping figured it out stupid super trapp muffler was to restrictive loosen bolt and all is good.....