We developed the Direct Linkage System due to the complexity and availability of the factory 140 linkage. The 4 TBI is designed to open all 4 TBIs at the same time and the same angle, so the direct link was developed to be an inexpensive and simple solution. This accessory is included in all Four TBI kits at no extra charge.
This direct link system uses the factory Corvair 2 Carb linkage and a linkage forks between the Primary and Secondary TBIs. The Primary linkage arms has to be modified with 2 small holes for proper operation and and some user adjustment may be necessary during installation to prevent binding.
Installation: After the holes in the primaries and the forks have been installed on the secondaries, they need to be installed the the fork and arms engaged and placed on the heads as one unit. After installation, adjustment is with a 3/32 hex head and check for binding. Unit should move easily without any restriction.
We also recommend a return spring on the secondaries as an added safety measure and to ensure precise opening angles are maintained.