North American Turbocoupe Organization

Looks like I will be changing my turbo in the spring. I'm currently running a GT35R and although the top end power is great, seeing full boost at 4000 rpms is not fun. I will likely be going with a t3/t4 unit. This turbo is only oil cooled so my first question is there anything to pay attention to when eliminating the water passages from the turbo? Right now, I have a single line that runs off the hose barb of the thermostat, tees in the middle to feed the turbo (drains into block) and then wraps around the engine block to connect to the lower intake manifold. I do not have a heater core so no need to feed that. If I eliminate the turbo water lines, can I just run a single hose from the thermostat to the lower intake manifold? I would plug the drain port on the block of course.

My second question regards the lower intake to engine gasket. Due to the water passage, I'm guessing those who have had to replace it put a small amount of RTV on the gasket? I will be changing this as well for a ported unit.

Use a pipe plug (1/4" NPT I THINK??) to replace the bung on the pass side of the block near the starter. Maybe some kind of rubber cap secured with a hose clamp on the bung on the metal heater line or if you are ambitious, pull the heater line off, cut the bung off, and MIG up the hole.

I always put a THIN layer of RTV Ultra Black on water pump gaskets or any gasket that sees coolant. Never had so much as a small seep of coolant.

Thank you Jeff. I followed your advice for a recent water pump replacement and it has been leak free since.

I have once again changed plans. I will likely keep my current turbo setup and bite the bullet for a ported head. I'll never get the power levels I want without a ported head.