Quite awhile ago there was a topic regarding Hi Flow Thermostats. One that was mentioned was a Hi Flow 170 Degree Stat from Napa. I got One and it works great. I don't remember the Napa #. Does anyone know the # I am looking for? Something like THM 7 maybe? Thanks I found it. THM 6

  

Don't know the NAPA number.  I bought mine locally from NPD.  It's their part number T-8575-3 $19.60.  It's probably available cheaper elsewhere.

I found the Napa # THM6. I have One in mine and it works well. Never could get the Robertshaw Ones to work for some reason. Tried 3 and gave up and bought the Napa One. Friend wants One.

  

Yep - THM-6


54 Victoria 312;  48 Ford Conv 302, 56 Bird 312
Forever Ford
Midland Park, NJ

Ordered from NPD yesterday along with gaskets. Guess I'll finally have the right one this time.

56 Vic, B'Ville 200 MPH Club Member, So Cal.

Hey all, I installed the 170* from NPT today any all went very well. Along with the old high-flow 160* Mopar unit it always stuck closed after first startup; it always did open but not until approx 190* and then shot down to what I determined to be 160*. Bugged me but I let it go these last few years. The new one worked in a sauce pan on the stove at 170* and when doing the first test in the car showed water movement with a cardboard in front of the radiator and 169* at the neck of the bypass hose into the top of the water pump. I do have a 1/8" hole in a plug. The new reading on the factory gauge is now about 2 needles with higher than before and where our 56 always ran as I remember in the early 60's.

There is a note in the thermostat box that says you need 1-1/2" between the front of the manifold to heater line and with the dual quad Edelbrock manifold and the deluxe heater vacuum actuated valve there was only 1/2". To make it clear the thermostat only needed to be clocked vertical on it's interior structure as not to interfere with the valve; so all was good.

Next project is to get the speedometer reading correctly after the install of the new Explorer 8.8 with 2.73 gears. The smallest nylon gear i can find is a 19 tooth and 17 is whats needed or maybe even less. I'm working with Rusty @ Speedmeter Service in Colorado (HAMB) and Steve at Texas Electrical Instruments with an adapter to keep it all mechanical and it all looks good and will keep the cost a lot lower that a GPS conversion or GPS to mechanical with these older transmissions..I hate jacking up the car a foot and crawling under but what's a guy to do....









56 Vic, B'Ville 200 MPH Club Member, So Cal.

I tried 3 of the Robertshaw Type and never could get them to work properly. I have used the Napa Hi Flow all last Summer and found it worked really well. Consistent
Temperature with very little Temperature movement up or down.

  

I know there are different ones and designs but  i really don't remember one from another. I know the "bellows" type would never have fit with the room I had in the manifold. The one I took out was for a Mopar and hi-flow which I was sure I needed back when I was have heating up problems. It may have been marketed thru Mr. Gasket. It had approximately a 1/2"  "cup" with 3 oval holes in the bottom and a large opening into the hose housing. The one I received from NPS was in a Casco box and it is the open spring type  with a large opening like the first hi-flow and is listed in the NPS catalog as a hi-flow.. 

56 Vic, B'Ville 200 MPH Club Member, So Cal.

Sounds like the One sold by Napa. Bigger opening than Standard Stats.

  

As far as the speedo gear, what trans are you using?  If you are using a 57 or later with the redesigned gear, look for a gear on ebay.  If it's an earlier trans, your options are a lot more limited.


54 Victoria 312;  48 Ford Conv 302, 56 Bird 312
Forever Ford
Midland Park, NJ