Would high-volume oil pump help?

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pauls340

pauls340

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My 340's oil pump is 21 years old and the oil gauge seems to indicate a little low so thinking about getting new oil pump. Any suggestions? Cars stock with a slightly built 340 w/ 4spd. Doesn't burn any oil or eat any more than normal. Is there a oil pump that is much better than stock OEM but doesn't change anything else? Thanks
 
High volume pumps dont usually change the pressure, they just move more oil around, a high pressure pump would change the pressure.

But the real question is how old is the motor? The oil pump may be fine and there is some other reason for the low oil pressure. Did is just randomly start to go low?
 
The above statement is correct. HV pumps move more oil, HP pumps move more pressure. The only real reason I see for an HP pump to exist is for engines at a continuous low rpm, like industrial or agriculture. I have honestly never known anyone to use the HP spring that comes with most oil pumps. Now despite the fact that this thread will more than likely turn into an off topic mess of people arguing if you can run a HV pump with your stock pan (which you should never do fyi) neither an HV. Or HP pump is really necessary for what sounds like a dedicated street car. Either let sleeping dogs lie since its running ok, and maybe bump up a little in oil weight to gain some pressure back on a tiring pump. Or pull the engine to put a new, oem $30 oil pump in it. I think you are ok. Probably something I wouldnt pull the engine for if it just seems the gage is a touch low. But their is also the preventative maintenance side to it. So up to u.
 
I've run HV pumps with HP springs for years with no problem with stock oil pans. You have to do a little banging to get the clearance in the pan for the taller pump, but it can be done...

MP pumps come with 55-65 psi springs

You can upgrade to 75 with their HP spring kit.

All mellings pumps have a 72 psi spring...
 
pauls340 said:
My 340's oil pump is 21 years old and the oil gauge seems to indicate a little low so thinking about getting new oil pump. Any suggestions? Cars stock with a slightly built 340 w/ 4spd. Doesn't burn any oil or eat any more than normal. Is there a oil pump that is much better than stock OEM but doesn't change anything else? Thanks
Click to expand...


is this reading from a factory gauge,

i would first, double check the pressure with another mechanical guage
 
HV oil pumps are not meant to be a mask for a worn out engine.
 
Paul, it's quite possible you have something else going on based on your other thread.

That oil blowing out of the dipstick tube may be from something related to your low oil pressure.

Can you be more descriptive about everything you are seeing?

When it started, gradual or just started? etc etc.
 
The motor is worn out. You have one thread about low oil pressure and another about excessive blowby. Do the math.
 
What I mean by slightly build; I've had the car 21+years and it was built/restored by 3 farmers in Illinois, in a barn. I bought a new 71 Demon340 in 71 and the cam didn't lobe like this one so I'm assuming it is slightly built; stock intake,stk carb,stk 4 spd, stk 3.55, stk rallye gauges. RRR is (unfortunately) probably right. However, it in no way runs tired. The visual oil gauge reading has been low on and off for three years. It sits for 3or4 weeks at a time and when I drive, it's not usually more than 25 miles. I noticed a little exhaust smoke yesterday while taking off at a light. If I got 22 years of fun, maybe it's just time?
 
pauls340 said:
What I mean by slightly build; I've had the car 21+years and it was built/restored by 3 farmers in Illinois, in a barn. I bought a new 71 Demon340 in 71 and the cam didn't lobe like this one so I'm assuming it is slightly built; stock intake,stk carb,stk 4 spd, stk 3.55, stk rallye gauges. RRR is (unfortunately) probably right. However, it in no way runs tired. The visual oil gauge reading has been low on and off for three years. It sits for 3or4 weeks at a time and when I drive, it's not usually more than 25 miles. I noticed a little exhaust smoke yesterday while taking off at a light. If I got 22 years of fun, maybe it's just time?
Click to expand...

Cheaper to freshing the engine up now running, instead of one with a rod hanging out.
 
Paul, since you said it's the factory gauges I'd find a known good aftermarket to test against it. It's quite possible it has more pressure than you think
 
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