Oil pressure '65 327/250HP? Too low at Idle?
05-01-2018, 06:54 PM
#181
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My experience was before SBC high pressure springs were available or known to me. All this information used to be found in Hot Rod books and other publications of the era.
You may still be damp behind the ears and missed out on some important information because you were born too late.
Two shims is all you needed and no, I don't remember the thickness.
You may still be damp behind the ears and missed out on some important information because you were born too late.
Two shims is all you needed and no, I don't remember the thickness.
05-01-2018, 06:54 PM
#182
Safety Car
If you look at the cutaway you'll see the spring is close to coil bind. We used to shim them with a washer or 2 up to the thickness of a cam degree bushing because it fit and we had them. But if you stack up the spring with too thick of washer the pump isn't going to bypass correctly. Which is why I finally said I'm just going to start stretching them . As I noted earlier I stretch stock springs 1/4". Never had a problem. Or use the pink spring. But they don't make a 'pink' spring for everything. The last couple I remember were a 4.3 v6 I built for a friend in a model a Ford truck, 40 idling 60 at 2800 same pump as a 350, and a 396 for a 67 Chevelle I'm not certain but I think it had the same maybe a little more. When it came to me one of their complaints was very low oil pressure. I called the guy to ask and he couldn't remember either. They are fresh motors with good clearances. There are too many variables to say what any random motor might have. When I ran the shop we stretched them all 1/4". Otherwise it wasn't uncommon to see 15 at idle which shouldn't hurt anything but people will complain about it. We never recieved complaints the way we did it. But we also learned pretty quick DO NOT ever use a high volume pump in a Ford. They have narrow cam gears and we had several wipe the gears out. After that no more HV pumps for Ford street engines with cast distributor gears. You asked I answered as best I can.
05-01-2018, 07:20 PM
#183
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If you look at the cutaway you'll see the spring is close to coil bind. We used to shim them with a washer or 2 up to the thickness of a cam degree bushing because it fit and we had them. But if you stack up the spring with too thick of washer the pump isn't going to bypass correctly. Which is why I finally said I'm just going to start stretching them . As I noted earlier I stretch stock springs 1/4". Never had a problem. Or use the pink spring. But they don't make a 'pink' spring for everything. The last couple I remember were a 4.3 v6 I built for a friend in a model a Ford truck, 40 idling 60 at 2800 same pump as a 350, and a 396 for a 67 Chevelle I'm not certain but I think it had the same maybe a little more. When it came to me one of their complaints was very low oil pressure. I called the guy to ask and he couldn't remember either. They are fresh motors with good clearances. There are too many variables to say what any random motor might have. When I ran the shop we stretched them all 1/4". Otherwise it wasn't uncommon to see 15 at idle which shouldn't hurt anything but people will complain about it. We never recieved complaints the way we did it. But we also learned pretty quick DO NOT ever use a high volume pump in a Ford. They have narrow cam gears and we had several wipe the gears out. After that no more HV pumps for Ford street engines with cast distributor gears. You asked I answered as best I can.
Okay, Sound like you have a handle on it. Thanks!
05-01-2018, 09:20 PM
#184
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C2 of the Year Finalist - Modified 2020
My 66 350 hp 327 was reading low oil pressure at idle. Idle was set at 750 rpms. It turned out the person I bought it from replaced the gauge. When he installed the tubing line onto the back of the gauge i believe he didn't hold back on the 1/2" brass block attached to the gauge when he tightened down the 1/8" ferrule. What happened was the block rotated slightly counter clockwise moving the needle to the left. The fix was simple. I used a 1/2" open ended wrench and a mirror to move the block back. You want to make sure the block is aligned vertically on the back of the gauge.
Dennis
