Hey all, I recently replaced the radiator in my car and the heater core has been disconnected since I got the car, but aparently on the new radiator there was a hole for it but it was capped off with a rubber cap, but this morning it just started leaking.. Can someone tell me if those caps aren't meant to stay on there like that or what? (It's been several months since I replaced the radiator). Also, if I did hook the radiator core back up, would I lose in HP? TIA!
(Also, this is on a 1989 Camaro RS 350 Convertable)

 

I can't say for sure but I think those caps were designed mostly for keeping debris out of the radiator during shipment. Whether they're designed for long-term block-off I have no idea.

One thing I can tell you is if you are bypassing the heater core you shouldn't just cap and block the lines. The water pump likes to have some circulation through the heater core lines, jsut to keep coolant circulating inside the motor to prevent hot-spots from forming. So don't block-off the lines, just run them straight from the intake manifold directly back into the heater core return line in the pas. side of the rad. In other words, a stock hose routing but bypassing the heater core.

I assume you heater core is leaking, plugged or otherwise messed up and that's why you don't want to pass coolant through it.

 

Actually, I don't know why the heater core "was" blocked off.. but I took the plug out of the hose a couple hrs ago, hooked it into the radiator and bam, everything works perfectly + my car doesn't seem to run as warm as it did, and my heater/defroster works.. so I'm relatively happy at the moment.. I know that when I replaced the radiator, the old radiator had no heater core outlet on it, maybe thats why it wasn't hooked up? But why would someone put the wrong radiator in there? Oh well, fixed now.. but one question, I've seen a couple of posts on this but no real direct answer I don't think, does it cause any hp loss to have the heater core hooked up?