[Brad B. Hillebrand]

Well, I still don't have the diameters of the pulley you are using but you can use you my spare AC WP pulley to see if that helps. Keep it for at long as you need to, when you find an AC pulley, just send me the one you buy. I think it's more of a water flow issue with a potential hot trans thrown in the mix. I also have a spare original Harrison 4 core you can try. It's been sitting, but clean for about 6 years, for auto trans and worked well when I removed it from the car. It's an AC rad. so it can handle a little more, I assume you don't have a 4 core now....

HIGHLY recommend getting a new T-stat. They are not all made the same, I learned that the hard way. The stewart T-stat will cost about $10 bucks and a few for delivery...it will increase the water flow at all fan speeds.

The other stuff should be tried too, yeah, the rad is a killer cost.....

Let me know where I can send the pulley and if you want to try the rad...

Brad

[dave bolduc]

wow.....nice site....but what stat would you use for a 69 350 4bbl, 160 or 180 degree??

i see ford and chevy, will it fit - not mentioned anywhere on site

thx...dave

[Geoff]

Gteeo 67,
I have done much experimenting with V8 cooling. What I have found is that a flex fan ALWAYS cools better than a clutch fan, assuming the flex fan is the same OD, has 6 or 7 blades with comparable blade area & pitch as the clutch type fan. The reason is simple: the flex fan spins faster & therefore pulls more air, because tha clutch fan slips & has reduced airflow. I use the genuine Pontiac Ram Air 7 blade flex fan. No fan I have compared [ fixed, clutch, electric, other flex ] works as well. I have also found that at over 50 mph, the flex fan maintains lower temps than a clutch fan. Yes, I know the theory says that a fan is not needed above 30-35 mph, but I have found otherwise. Your water pump/fan should be turning faster than the crank; if you have a 8" crank pulley, you should aim for a 6 1/2" to 7" pump pulley. Also, as mentioned by others, you should use a 160 HIGH FLOW thermostat, such as the Milodon, MR. Gasket, Stewart Components.

[General Z]

Ok, guys, I have tried all of this stuff, and then some, and it only seems to get hotter?

1970 455 in a 67 Firebird. I don't know what the radiator is out of, but it appears to be bigger than stock. I had a water pump with a stamped impeller and had already adjusted the plate to fit with this pump. Then, I got a cast impeller pump, and tried to bend the plate back a bit, because now it was way too close, as in, it was touching. I could only bend it back so much, cleanly, and thought I had it just right. Then, when I put the pump on the car, the I realized that the impeller was rubbing on the plate a bit, but left it, figuring it would adjust itself pretty quickly.

This really didn't make me any cooler. It was running around 205 or so. Then I got thinking that for some reason, the car had a 7" crank pulley and a 8" water pump pulley, so I got a 8" crank pulley and a 7 1/8" water pump pulley. I also installed a spring in the lower radiator hose.

After doing this, the car actually ran even hotter, getting and staying over 210.

I have a Milodon high flow 160 degree stat and a DC Controls 18" electric fan with the potenimeter meter built in.

On paper this thing should be as cool as a cucumber right?

One bad thing I noted was that when I drained the coolant to put the spring in the lower hose, after settling the bucket of coolant had an oily substance on the surface. Actually, quite a bit. I pulled the oil drain plug, and let a little oil drain out, but didn't see any coolant.

The oily substance looks more like trans fluid. My trans fluid does seem a bit high, but the fluid on the dipstick looks great.

One other thing I noted while installing the new pulleys, was that the water pump seemed to still rub the backing plate, while turning it by hand.

Since technically, the only thing that changed was putting differnet pulleys on, which sped up the water pump, I am thinking that maybe there is now too much flow and the radiator can't keep up? Maybe I need a non high-flow thermostat, or a hotter thermostat, like a 180?

Thanks guys, stressed and depressed here.