Heater Hoses And Cooling Effect

[toofun]

I have heard that you can run alot hotter when you remove the heater hoses from the motor.(mine were originally run to the front of the aluminum manifold and to the back of the manifold. Is this true?? I have a 383 with aluminum heads, BE COOL radiator and 16 inch Spal fan. I use to have no problem with cooling and seldom needed the fan when I had a stock iron head 350 in the car. Now with the ALUMINUM 383 motor in there I have to keep the electric fan running all the time even on the highway and the temp stay at 180.

I know 180 is not a problem, but I would think that an aluminum head motor should cool better. The only two things that are different besides the motor is the HEATER HOSES were removed to clean up the engine bay and I have a block off plate under the hood at the radiator support. This plate I figured would help more with cooling since it does not allow any hot engine air to get sucked back in front of the radiator. Would connecting the heater hoses back solve my problem or do I need to look elsewhere.



Thanks
Mark
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