400 cooling and oil pressure issue

I don't really see a problem with your oil pressure, but the idle pressure is a bit low. I don't think you meant that you have the High Volume oil pump, that should not be necessary with a new TA cover. Who set the oil pump clearances, TA, or someone else?

A/C adds a heat load to the system, the condenser in front of the radiator gets hot and is cooled by the air that is drawn through it, and the then the radiator, so it isn't surprising that you are running 10-15* hotter with the A/C going. What radiator are you using? What is your ignition timing at idle? Retarded ignition timing will heat an engine up quickly.

Yes, you may be able to add an electric solenoid to bump idle speed when the A/C compressor is engaged. The early 70's Buicks used them, but there was a provision to mount them to the intake manifold, something your 69 intake wouldn't have. You'll have to fab something up I suppose.

Yes, aluminum radiators can help a lot, but make sure you get one with big tubes. The best aluminum radiators use 1 or 2 Rows of tubes. If you see one with 3 or 4 rows, pass on it. The best aluminum radiators use 1" tube size, 1 1/4" is even better. If you aren't concerned with correct looking radiators, you can pick up a late 90's Park Avenue radiator with plastic tanks that will get the job done. Be Cool makes a 2 row radiator with 1" tubes. Do a search here on V8 on aluminum radiators.

 

Hmmnnn, yeah, but I doubt he would have 60 psi @ 3000 RPM.

 

OK, that is the high performance oil pump assembly. That is not the high volume/high pressure pump kit with longer gears. Those became unnecessary when TA reproduced the timing cover. So you have 1533A (?) assembly, and that means TA assembled it and set the end clearance. You are using 20W/50 oil, yet you have low idle oil pressure? That only leaves bearing clearances. A shop unfamiliar with Buick engines can set the clearances on the loose side. That will kill hot oil pressure.

As mentioned, make a 30* mark on your balancer. Standing in front of your car, measure EXACTLY 1 3/4" clockwise along the balancer from the factory mark. If you prefer, 2.00" is 34*. Then you can use your timing light. Rev the engine until the weights are all the way out (light springs help here) and see where the 30* mark ends up on the timing tab. Then just do the math.

As mentioned, Chevelle radiators use a bigger lower hose (1 9/16" or 1 5/8"). The most important thing to remember is you want 2 rows with the biggest tubes (at least 1").

 

What is the timing at 2500 RPM with the vacuum advance connected?

 

If it's a street car, you need vacuum advance. It will run cooler with it.

Picture size is too big. All you need is simple photo editing program like Irfanview.

http://www.irfanview.com/main_download_engl.htm

 

Back in 2005, having seen post after post about ignition timing, I started this thread,

http://www.v8buick.com/index.php?threads/power-timing-your-buick-v8.63475/

I think by far, the most confusing topic for car enthusiasts is ignition timing requirements. The biggest reason for that, is a lack of knowledge of ignition advance basics. How the mechanical advance and vacuum advance actually work inside the distributor, and what that looks like when using a timing light to measure the amount and rate of advance. This is extremely important to how your engine runs. If every distributor ever installed in every engine were exactly the same, then everyone could run the same timing. They aren't. The distributor specifications vary from year to year and engine to engine. When dealing with a car that is 40-50 years old, and you are not the original owner, it's highly likely that the engine has parts that have been changed before you ever saw the car for the first time. Of course that includes the distributor. We aren't even considering that engines get rebuilt changing compression, valve timing and induction, and exhaust. You would be surprised how many guys will get a car, and then proceed to set initial timing to what the book says for that particular year car and engine despite the fact that EVERYTHING else for that engine has changed. Just tell me what should I run for initial timing they ask me. I can't, I tell them. Everything changes once you modify things with different parts not even knowing exactly what distributor is installed. In the above thread, I explain advance basics, and how to use a timing light to measure the advance. You can gain a lot of performance by speeding up the rate of mechanical advance, getting it all in by 2500-3000 RPM, or even earlier. Once you do that though, you must limit the amount and sometimes the rate of vacuum advance. Ignition timing can greatly affect how cool or hot an engine runs. So the answer to your quoted question is, maybe, I don't know. Read the first post of the linked thread. Let me know if you understand it, and have questions about it, and I will try to help.

 

Yes.