The sun is out, it's a Saturday, I had a ton of errands to do this morning. Perfect day to go cruising in my Mustang. Except for one thing, it's frackin freezing....I mean literally 34 degrees. So I do go for a drive in the cold with a jacket and a sweater on, but seriously. My Mustang just doesn't have any usable heat because of that massive thermostat. All the water goes to the radiator, and nothing goes up to the heater core.
I'm still running the stock heater rail, and I do have a bypass hose on it. Since the bypass hose is almost worthless anyway, for the last few years I have had a restrictor in it to maximize flow to the heater core and radiator. I have considered buying an auxiliary water pump to get more hot water to the heater core like this on:
but honestly, I'd rather not add more crud to the engine bay if at all possible. I'd rather have fewer things in there. Since the bypass hose is practically unfunctional anyway, I was wondering if I could just run the heater core in line where the bypass hose would be. Then it would be supplied at the same level and with the same dynamic pressure as the thermostat. I could simply remove the factory heater rail at this point as well. I moved the water temp sensor to the water outlet a long time ago since it wasn't getting any hot water at the heater core.
Sometimes input from others really helps. You can't think of everything. Last year I was putting my transmission in, and couldn't get it to sit right. My wife got under the car with me, and she saw it another way and I got it in there. A different perspective always helps.