how hard did you stop? you may have forced all the oil out of the sump area and got air into the oil pump for a few seconds. I wouldn't worry, every time you start your car the same thing is happening for a few seconds until the pump is primed.
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pontiax- (canadian pontiac X frame)1964 Parisienne 2dr. Hardtop ,lagoon aqua metallic (Q) ,421 cid Dart Industries block and heads. 550 hp. 575 ft lb of torque.
Had it happen in a 283, a few times. Turned out the oil pickup was loose. Have a look at your oil pan for any dents, just in case. Although it does sounds like all the oil went to the front of the pan.
I don't want to scare you Mark but I don't think you should ignore the light. That's a brand new engine, right? I don't think there is any way that should be happening. Even under hard braking there should be lots of oil to the pump. Think of people driving downhill on steep streets like San Francisco who come to a hard stop. To begin with, the oil is already way forward in the pan, then they brake hard and slosh even more forward.
I think I would install a mechanical gauge and just make sure the light is functioning correctly first of all.
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1966 Strato Chief 2 door, 427 4 speed, 45,000 original miles
1966 Grande Parisienne, 396 1 of 23 factory air cars
It's not a new engine, it was one that was run in a late model stock car at Peterborough for 3 seasons, and it was always up in the running or on the hook (the car was DNF for wrecks a lot) . It was pulled and gone thru professionally. The heads were rebuilt and it got a new timing chain. It lived a rather hard life to be sure, but all it actually needed was a valve job and a chain with gears. All the internals were in very good shape and really didn't need anything.
When hot I see 15-17 psi at idle, 40 or so at highway speeds. Numbers I'm led to believe are typical. I have a new AutoMeter SportComp mechanical oil pressure gauge, so I assume it's accurate. I decided to "T" off at the rear oil outlet, so I could still include the idiot sender.
The engine runs quiet with no real lifter noise, is knock free and burns no more than I'd say.. .5 liter of oil every 4 k or so. Emits a light puff of blue at cold start up (I assume valve stem seals), the plugs are all nice and clean and show no fouling at all.
I run Mobile1 10/30.
I can say that during max braking, the engine does almost stall. It's never been able to pull down so hard before as to come close to a stall.
Perhaps the sender is grounding just a little early. This combined with the low idle pressure and low RPM might be the culprit.
Could the Synthetic oil affect pressure down low? I need to eye the gauge when and if it happens again.
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65 Laurentian post, 67 Grande Parisienne 4 door HT.
If it's almost stalling, I think that is your answer Mark. On a typical engine, if you would have the engine hot, in gear, and turn the idle right down to almost stalling, I'm betting the pressure would drop enough to turn the light on. That is likely what happened when you were on the highway.
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1966 Strato Chief 2 door, 427 4 speed, 45,000 original miles
1966 Grande Parisienne, 396 1 of 23 factory air cars
