Lower rad hose question

[boilermaker]

Hi ,
Got a 75,000 225 slant in a 68 rag Dart GT.
Replaced all rad hoses this year and all was good.
Car has 3:21 gears and 26" tire so 3200 rpm keeps up on the highway.
I have found the car gets hotter the more rpm. 160 deg thermostat and new rad cap. The new lower rad hose came without spring so I installed.
After a 100 miles found the hose collapsing at higher rpm.
Installed new spring in lower hose and now car is running even hotter (190-200).
Should I install a lower rad hose restrictor (I know the thermostat is some what of a restrictor).
Just thinking that the collapsing hose allowed the water to have a larger "delta T" at the rad.
Also any thoughts on slowing down (larger pulley) the water pump to assist in the cooling at the higher rpm.



Thanks in advance.

 

[67Dart273]

If the lower hose is collapsing it's because the rad is somewhat restricted. Since the system is a closed loop, the pump should not be able to "over pump" the radiator flow.

 

[RedFish]

Restriction in the radiator is why the lower hose collapses.
Even so the first thing to do is get actual temp readings. The stock gauges are only range indicators. They depend on a power supply that can vary with engine rpm so their reports may all be a questionable.