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Discussion Starter · #1 ·
OK so my 77 nova with a 350 just starting sputtering and stalled out after 45 min of driving and it starts up and idles no problem afterwards but when I put it in gear my oil pressure drops and it shuts off. No noises or anything coming from motor when running. My oil pressure when idling in park is 50 psi and idling in gear is at 20 psi. At a complete lose as to what it is besides maybe the oil pump or sensor . Was wondering if anyone else has had this issue. Thanks in advance
 

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You mentioned vapor lock in your previous post. That is caused by the fuel either being affected by an extreme drop in pressure (such as a fuel pump sucking hard), or too much heat from the exhaust raising the gas above the boiling point (which for high octane gas is 104° F degrees; but rises as high as 392° F the closer you get to the low octane stuff we run in the summer months). Vapor lock is liquid gas vaporizing and the vapors can not be pumped with a diaphragm style pump, it requires a positive displacement pump in the rear of the car pushing the gas forward such as are used in electric fuel pumps.

What you are describing now could still be a lack of liquid fuel in the fuel bowls, or a bad HEI module breaking down due to heat build up.

The factory uses a rev limiter built into the HEI module of all BBC distributors. It is preset to 4,600 RPM and can not be changed. This was done to reflect the limitations of the TBI used on these engines, as they would go lean above 4,200 RPM (or at high altitude) damaging the engine. If your HEI came out of a BBC it could be the issue. I mention this because the 454 is a frequent source for a divorced coil small cap HEI (the other source was the third gen Camaro). If it came out of a Camaro it doesn't have a rev limiter as the Camaro used TPI on top of the 305 fed by an in-tank electric pump that ran at a much higher fuel pressure.

Either way the factory HEI module doesn't like high RPM operation as the transistors heat up faster than the heat can be transferred to the heat sink. Aftermarket HEI modules come with a better heat sink and they use Mil-Spec transistors that can continue to operate at higher temperatures. Those Mil-Spec transistors are three times the cost of industrial grade transistors which is why they are not used by GM.

Since heat is the enemy shedding heat is critical. You must use a special paste to transfer heat not di-electric grease as I have seen some shade tree mechanics use. The heat transfer grease will dry out and crack forming voids that doesn't transfer heat. Because of this it should be wiped off and replaced occasionally.

I recommend MSD replacement modules over the factory units, even though MSD like most aftermarket manufactures fell on hard times during the past great "Recession" (not to be confused with a Depression as that isn't politically correct to say). There were reports of quality issues on some of MSD products. But I would still recommend the USA made MSD over the off shore Accell product line.

Big Dave
 

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Discussion Starter · #3 ·
OK thanks will look into that it was just I ran the car wensday to work and it ran fine no spitting or sputtering and it was about 10 degrees hotter that day then on thursday. I looked in the carb. And pulled the throttle cable and fuel flowed out of the Jets no problem. But as soon as I let the motor cool down to about 130 degrees it fired up and went into drive no problem.
 

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Discussion Starter · #4 ·
Okay so now I have another issue I checked my oil level before starting the car my oil level was at the full mark on the dip stick after I started the car I heard a slight ticking noise coming from the driver side. My oil pressure gauge said I was at 60 psi . So i turned the car off and checked my oil level again . And it said I was about 1qt. Low.
 

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If you check the oil immediately after shutting off the engine, oil is still trying to make it back to the oil pan. Also the ticking doesn't mean you are low on oil. Some lifters/rockers tick. You could also have a exhaust leak. When an engine is cold your oil pressure should be higher than when you are in gear (normally) as the oil thins out as the engine gets warmer causing a lower oil pressure. 20psi at normal engine temp in gear is not necessarily bad.
 
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