1969 429cid; pegs oil needle till 2500-3000; above that pressure goes down; let it idle and pressure comes up runs great otherwise; 10 to 1 standard bore,streetmaster,old 4100 autolite off of 428; all in a 77 250 hi-boy

 

Hook a mechanical gauge to it.
Ford's gauges are not the most reliable.

Look for 50-60 at rev then drop to about 20 at idle.

How many miles on the engine ?

 

oil press guage is accurate; 20.000 orig miles ( i was told);replaced pistions with forged; all new bearing except cam;cyls had no wear; old bearings looked good

 

High volume pump sucking the pan dry??
It often happens with a stock oil pan.
Jimmy

 

is there a pressure relief spring in the pump- you might be able to switch to a stiffer spring to bring the pressure up. not sure is the 429/460's have these or not. Anybody?

 

reviving an old thread, but didn't want to start a new one.

I'm running Oreily's 10w-30 in my 429. Cold start will give me 80-85psi oil pressure. When hot and at idle it's down to 30psi and increases with RPM as expected.
Anyone concerned about these numbers? Last thing I want to do is overpressure anything.

• I do not know if there is a high flow pump installed (how can I tell?)
• The engine has a cam in it from the previous owner - I do not know the details.
• I live south of Houston (aka its hot a lot) so thinking 5w-30 might be a more comfortable oil?

thanks for any input.

 

Not concerned about those numbers
If you compare a HV oil pump to a regular one, the rotor is longer on a HV pump