Technical SBC Oil level from bottom of block?

Yup.

36 posts of debate between you and I saying the same thing.

 

No worries. The pile of parts is what GM put together in ‘89. I’ll use better references for measurements than eyeballing across the pan rails etc.
I could have easily stacked up a 1/4 inch here and there.

 

Are all the dipstick tubes on Chevy smallblocks the same length ? Chevy also had both 4 quart and 5 quart oil pans available. Also, the volume of the oil filter will affect the reading you get . The only way to be sure is to put the correct amount in the pan you have and then see what the reading is on whatever dipstick you have. Then when you put the alum pan on, pour till it reaches that mark. I think the main thing is that you don't have so much that the crank can hit it, but enough so that the pump can't pump the pan dry or uncover the pickup. An aftermarket pan may put your stock pickup farther from the bottom of the pan. I would check that distance.

 

I appreciate all of the responses and yes the general consensus for resolution is find a pre 79’ OEM/factory GM dipstick and this will give me the proper height of oil regardless of oil pan capacity and design. My issue is finding an old dipstick where I am 100% it is an OEM pre 79’. All of the local engine builders or hoarders have pitched these along with parking brake related items, it’s crazy!

in have acquired a 64’ steel 327 (5qt I think) oil pan that I will eventually put on. If I can find a 100% genuine GM dip stick I will take a measurement of the full/min markings in relation to the bottom of the block where the pan bolts up. This way if someone else does not have access to the pan capacity, OEM dipstick, etc etc they can simply measure the aftermarket one without running around spending time and money to have the proper oil level and dipstick markings.

 

I measured the distance from the block to the "full" mark on the dipstick, and got 3.5", with a reproduction 327 dipstick and tube, that takes the right amount of oil to fill to the full mark.

This is just below the crankshaft, too. What a coincidence.

 

So let’s see if the below pics are better. Do not there is a speed bump dent in the sump of the pan.

 

So 2-3/8, 5, and assume Eddy is right and my pan should be 7-1/2, not the 7-1/4 I have with the dent.
Puts the bottom of the pick up right where Jim and yourself said.
See, I can admit to bad eyeball measurements and mistakes!

 

It doesn't matter if you have the right dipstick, as long as you mark the one you have to the 3.5" dimension.

 

Best, as stated is an OEM dipstick, and it does not care what pan you have, it's registered in block.

Mr Gasket dipsticks are swap meet items.

Depending on stroke, oil windage is your biggest concern. On open pans, a windage tray is a nice addition.

Worked for a Diesel Eng Co. Windage tests were interesting developing oil levels at allowable tilt angles. I remember in one test where 1in. Caused oil to walk up side of block 4in above pan gasket. 2100rpm. Crank was not dipping.

 

On a SBC with a lot of stroke like a 383 a good oil pan with baffles a kick out, tray etc can gain 15 HP or more over a stock pan with the standard 5 quarts in it .

When I was limited to a standard pan due to chassis restraints on a 383 that i spun fast .
I ran the level were about 4 quarts would be and then big twin remote filters I had 6.5 quart capacity .
On a dyno I gained 11 HP with a oil level change that was at only 6500 RPM. I also had more stable oil pressure with less drop off at the end. We're do you gain 11HP for the cost of a oil filter adapter and a extra $5 filter ?

I have seen reports were big inch engines gain 30 HP with high dollar tricked out pans that control windage.

On the OPs question I have a stock dip stick and tube I use to set level on stockish engines .
On a deeper more capacity than stock pan I lower the level not run more oil to reach the same level.
Sump lower of course.

 

I believe camera parallax distorts the angle.

 

Just a few thoughts.
1. Fabricated sheet aluminum pans will dent as the result of an impact. Cast aluminum pans fracture as a result of impact about 99% of the time.
2. As to the oil pump pickup position relative to the oil pan bottom. Whenever I assemble a oil pan and pump pickup parts combination for the first time, I will calculate what I expect but verify with modeling clay. For this slanted pan I would want to know the different clearance distance between the front edge of the pickup and rear edge. May not be enough to matter, or could be enough that I would match the pickup angle to be parallel to the pan slant.
3. As to pan capacity and dip stick calibration, make a mark inside the empty pan down 3 1/2" from the pan rail. Fill pan to line to get capacity to that level. Install pan, add that amount of oil plus an allowance for the filter size used. Start, run, let cool, mark dip stick full mark. Add a lower mark if desired.

 

Adding a little detail to this thread for future reference. On a new to me '87 SBC crate motor (block #1409363, passenger side dipstick), I questioned the aftermarket flexible dipstick as it read overfull with 5qts (total) in the motor after run-in, with a stock pan.
Not having time to pull the good running motor down, I bought a genie GM tube (#12551154) and dipstick (#12551144) for the stock motor.
Shoved said stick into tube and measured from the block mating point on the tube to 'full' line on the stick. 6" on the dot.

Measured the tube length sticking out of my motor, added 6" and it matched where the oil level was sitting with 5qts in, well above the full line on the aftermarket stick. Made a new mark and called it good.

This confirmed I was not overfull and at risk of aeration.

Pics for reference: