On the Riv it took under a month to get the part, pre covid. The Wildcat I just installed took several months. I never had a problem in contacting the guys at Dewitt. Always answered the phone and gave me an answer but took way longer than I expected. Still having an issue with the cat so I got to start looking at another soultion.
Get a new radiator or drive around everywhere with your heater set on high temp & fastest blower speed.
At that speed you don't need a fan; so that was never the issue. Does your vacuum advance operate correctly? It is an important system for a street driven car. Easy to check; costs virtually nothing to diagnose; takes almost no time; immensely cheaper than throwing parts at an improperly diagnosed problem.
Or install a reversible blower fan and have the hot air blow to the outside instead of into the cabin
Good luck with OPGI. They're KNOWN LIARS about product delivery times. They're KNOWN LIARS about whether a product is on back-order. And they'll keep lying to you as you call each month..."yeah, that'll ship in about a month..." Then, when you call a month later..."Yeah, that'll ship in about a month..." When it was me, they didn't tell me the product was back-ordered before charging my card, my item was actually backordered for maybe six months, and in the meantime they were still heavily promoting the product, and even sent me a postcard advertising the product I'd already ordered and they couldn't supply. Like I should order another one. They claimed in the advertising that it was made in "their factory", but I finally got them to admit that "their" factory was in Communist China, and the quality was so bad that they wouldn't send it to customers. When the stuff arrived, after supposedly getting the product made "right", it wouldn't fit together--the bolt-holes didn't line up, and the console lens was scratched. Fookin' criminals.
Okay I finally got the radiator Friday. I looked up cooling system capacity for the 350 and found 16.5 quarts. Is that correct? that's over 4 gallons, seems like a lot.
One thing I was admit about when I put the Disco GS back on the road was I did not want to deal with it over heating. New water pump, Aluminum Radiator, and a 160* thermostat. I had to go to several auto parts places to get a good thermostat. You cant believe whats on the box you have to look at the actual Thermostat itself. I wanted a 180 or 185 but when I found a 160 I jumped on it. So happy I did. I can sit in traffic and the temp only ever gets up to the highest of around 185 and thats perfect. Buicks tend to like to run a little cool anyway. Took the car out yesterday and it amazes me no matter how hot outside it gets this thing just runs smooth and cool.
An OEM appearing aluminum radiator from BeCool has finally gotten my own heating issues under control (installed last Sep). HIGHLY recommended. YMMV. -MIG
Running 25 degrees over the thermostat rating at idle or cruise is NOT "perfect"; it's a sign of trouble with temperature management. Your thermostat has LOST CONTROL of engine temp.
X2, the difference in temperature between thermostat full closed, and full open, is approximately 20*, so a 160* stat is fully open at 180*. Once the system is more than 180, the thermostat is no longer in control, it's fully open. If you are running more than 10-15* over stat rating, there is a deficiency somewhere. The thermostat should open and close to varying degrees to maintain system temperature during normal engine operation. From the 1970 Buick Chassis manual,
Update. Radiator installed. Where engine ran around 210-215 on the highway it now runs at 180. Drove about an hour yesterday, highway, in town, it was 93 degrees out. Never got above 180 degrees. Have 180 degree thermostat. One more problem resolved. Next is heater core.
