Ford Muscle Cars Tech Forum banner

1 - 4 of 4 Posts

·
Registered
Joined
·
431 Posts
Discussion Starter #1
I am replacing my heater hoses that go into the
heater core. 1 is marked 3/4" but the bottom one
isnt marked and it looks like it might not be
the same size. Does anybody know if both lines are the same size?
This is for the 390
 

·
Registered
Joined
·
232 Posts
I just put 5/8s on mine friday.....

My heater core isn't hooked up, but both nipples at the motor were 5/8 (bought car and wasn't hooked up). Mine is also a 390.
 

·
Premium Member
Joined
·
5,813 Posts
You want a restriction on the incoming water so as not to overpressure the core. On my unit the incoming water is restricted by the water valve.

Another way is to use a smaller incoming (bottom) water hose, so I agree with Cheap that it is likely a 5/8".
 
1 - 4 of 4 Posts
Top