I am putting a 1977 350 into my 1991 RS Camaro (used to have an LO3 TBI). The water pump on the original 305 engine turns a different way to the pump on the 350. Also, the water pump outlet to the heater on the 350 is not on the 305 TBI water pump. I want to use the water pump off the 305 and all the original alloy brackets and the serpentine belt on the 350. Does anyone know the differences between the cooling system on the 305 TBI and the 1977 350? I have already spotted that the 305 radiator has a heater outlet on the header tank whereas the 350’s radiator hasn’t. Does the other heater pipe go to the rear of the inlet manifold on the original 305 TBI? What other problems am I likely to encounter? Or should I just use the original 350’s water pump and drive belt system?

Andy.

 

Just put all the late-model components onto the 350 block.

 

Thanks RB83L69!
Does this include the inlet manifold also? I am going to use the Rochester Quadrajet that is on the 350 so would like to retain the inlet manifold if possible. Is it possible?

Sounds as though you have done this before!?

Regards.
Andy.

 

You can use the carb intake manifold, as far as that goes; you might run into the issue with the center 2 bolt holes on each side being at the wrong angle, depending on what heads you have. That's easy enough to work around.

The early intake also probably won't have the rear heater hose outlet that is on the TBI; if not, you'll need to hook the "hot" side of the heater up to the front outlet on the intake. No biggie.

Of course, if you decide to use a carb, you'll have other issues besides the cooling system: distributor, computer if any, fule pressure & lines, etc. Or, there are adapters to mount the TBI on a 4-barrel intake, which some people are doing with all sorts of intakes.

 

Thanks again RB83L69.
I am going to use the inlet manifold that is on the 350 (1977 vintage by the way), so I can use the quadrajet. The middle bolts won't be a problem in that case. As you say, I will hook up the heater pipe to the front of the inlet manifold, and have the other heater pipe go to the radiator (as it does already). By the way, why did they change the water flow route?
The dizzy is going to be the one off the 350, the computer isn't there! (somebody pinched it (!), before I bought the car!). The fuel pressure and pipes will be the remaining problem.

Thanks again.

Andy.