Technical SBC Oil level from bottom of block?

I have researched a good bit and understand that the small block Chevy is 5 Qt (or 5.1) for the 350, but this is with a stock pan and stock dipstick.


My issue is that I have an unmarked pan and a Mr Gasket aftermarket dip stick reading well over full after 3.5 Qts and this can’t be right.


Does anyone know 100% what the oil max height distance should be in comparison to the bottom of the block where the oil pan bolts up? I’ve seen a few answers but I’m hoping someone here knows the true answer.


It’s a 73’ Camaro block and I need to do the 2pc rear main and the pan gasket anyway so I can mark the dipstick where the oil max should be and use the standard distance on there now to make a new minimum line as well.


This looks like a speedway or other brand aluminum cover but the bottom portion is slanted for better draining and the new finned aluminum models I see around look parallel to the block without this ‘drain taper’. I don’t want to do any damage running it overfilled (like wiping out bearings).

Thank you for the help!

 

I can’t help you with the dimension but if the engine originally took 5 quarts I can’t imagine you’d want to run too much less than that. I’d be slightly concerned with only 3,5 quarts, especially for any lengthy drive.
Is it possible there’s a windage tray holding oil and marking the dipstick? Can you take some measurements on the pan height (top rail to bottom) and compare it to a stock pan?

 

If it's empty and you know it needs 5 qrts then mark dipstick where ever it is. The pan is not that far off from stock.
I would ditch the aluminum pan. They crack and the only one I bought and used leaked. Never could get it to seal.
Steel pans dent. Less chance of ruining motor.

 

Love the car .

 

I've never seen a slanted one like that, I ran a CalCustom aluminum pan with a flat bottom like a stock pan on my t-bucket for several yrs, it was a standard 5 qt capacity.
I plan on running this one I picked up on my 57 p/u.

 

^^^^This^^^^

 

It would be best to drop oil pan to see pick up how fair off bottom of sump ,& if baffled,
Should be 1/4 to 1/2 inch off bottom of sump ,or look threw drain hole ...
5 qt pan sump depth is 7- 1/4 7- 3/4 from bottom of block ( typically)
I would say that pan is 5 - 6 qt with filter , a xtra quart would be about 1/4 inch ,fill with 6 , let it set for few mints then mark your stick cold ,,,
Most important is pick up to bottom of pan ,

 

To me, that looks like a bad idea and bad design. What the heck?

That just creates several problems. Chevy engineers are shaking the heads

 

I have gone through this several times and the only sure-fire way is to drain and refill the pan with the amount of oil in the manual, then re-mark the dipstick. If you have good oil pressure at , say 2000 RPM, then all should be good.
Any fluctuations at higher RPM could be the pickup sucking a bit of air and the location may have to be lowered so it is closer to the lowest point in the pan.

 

You really need to know where the pick up is located to the bottom of the pan. With that slant/angle if it’s a stock one I’ll bet it’s not near where it needs to be like said above 1/4-1/2” off the bottom.

 

Op need to know how far pick up / location ,,, if wrong pick up , Service manual says 5 quarts & typical OEM small blocks chevy is 5 quarts and the pick up is only a 1/4 of inch in the
""Oil "" it will starve the motor, run back not fast enough thats why in pretty much stock configuration a 1/4 - 1/2 off bottom of pan ,,, Stock SBC the baffle in pan is 3-- to 3-1/2 inch's off bottom of Sump ,

 

Lots of numbers came in but i didn,t see any offered about oil level in reguard to block bottom or more importantly the spinning crank shaft . i,m sure some space is definatly required reguardless of oil pan depth . Hope you get your answer from a chevy expert .

 

Well, I have a pan off a 1pc RMS SBC. I’m changing the oil in my truck on Tuesday, it takes 6 quarts So I have to buy a jug and a quart.
If you don’t get an answer by Tuesday mid afternoon (California time) PM me and I’ll use the empty quart bottle, and fill 5 quarts in it and get some sump/pan measurements.

Edit: Thinking about it further, the oil is probably a small distance from the bottom of your “slant” in the front of the pan. The slant is to let it drain to the sump.
You wouldn’t want it on the slant or stopping quickly etc, would splash oil on the crank.
Racers, road racers, etc use a windage tray to keep that from happening.

 

If you or anyone else has a stock pan, off the engine and can fill it with 5 qts of oil then measure the level from the top with the rails level you will have your answer.

 

I would measure the depth the crank counterweights drop below the bottom of the block and use that as a starting measurement. I would think you’d want a minimum couple of inches below that at maximum fill, maybe more. If running a windage tray you could get by with a little more fill height. Since it wasn’t designed as a splash engine, I wouldn’t want the crank splashing the pan every turn.

As to capacity, it’s usually measured by pan size and filter, 4 quarts in pan, one in filter. Not all filters will hold a quart, so any over what it takes to fill the filter is added to the pan volume. Put that close guess in the not installed pan, mark the distance for the fluid level then measure to the flange, then subtract the number you got from measuring the crank throws, that figure will be your clearance. You might find you can even add another quart without interference.
Like was stated above, mark dipstick accordingly. Also make sure oil pickup is within 1/4” of the bottom of the pan.

 

5 quarts in a stock sbc pan would be a quart overfull !

 

I was just going by what was posted before my post. Thanks for the correction.

 

You don’t want the crank counterweights or rod bolts dipping when the engine is at whatever installed angle is plus maybe another 20 or thirty degrees to account for parking on an extreme slope.

 

Hell, just dump four quarts of water in, less mess and waste.

 

Did you measure your dipstick against another sbc dipstick to make sure the length is correct ?

 

Reminds me of the time I was replacing an off topic engine and my brother was helping. We pulled the old motor and put in the newer one. He was moving stuff over from the old one to the new one and took the dipstick from the old motor while I was buttoning up other stuff. He then proceeds to put oil in it until it hits the full mark on the dipstick. Well, on fire up it is smoking like I am fogging for mosquitos. Couldn't figure out why and thought the newer engine I had picked up was toast. Turns out he had put over 7 quarts of oil into the engine to get it to full on the dipstick!. I had pulled the carb and could see oil laying on the intake runners of the manifold. So I questioned what he had done and figured it out. So I guess the lesson is, if you KNOW it only takes 5 quarts, (with new filter?) then put 5 in it and ignore what the dipstick says, or make a new mark where full would be.

 

That works unless you put on an aftermarket aluminum pan that may hold a lot more oil. Which is the OP's problem.

 

All that need be done here is to measure a stock setup.

Post the distance from the pan rail to the add line, and to the full line.

Nothing else matters.

Increased capacity oil pans add volume down, out, or both, not UP!

Yes, the pickup depth needs to be correct, but that is a separate issue from where the top of the oil is.

 

All other issues aside, the OP is better off with a flat bottom stock depth pan.

In this case, preferably steel.

This one is in the strike zone.

 

How does oil get from the pan to the intake runners?

 

Not certain. Only thing I could come up with was a vacuum line which ran from the valve cover to a plate under the carb was sucking in some of the excess oil when it was running. Only way I could figure it could get to the intake.

 

Through the breather system, when you overfill an engine massively the whole crankcase becomes one big oilly splashy mist and the breather pumps out oil into the intake.

 

The pickup location in relevance to the bottom of the pan doesn't determine oil fill depth. Oil fill depth is determined by level in relationship to the crank counterweights. Needs to be low enough for the counterweights not to slap the oil, but not so low as to lose oiling if you're cornering hard.
I can't see anything about the aluminum pan that would make me think it hold much different from a stock pan. That's 4 qts., plus one for the filter, unless it's a small oil filter that only uses 1/2 qt.
I'd run the engine to ensure the filter is full. Then drain the oil and measure out 4 qts. poured in. Let it drain down well, then push the dipstick in and make a mark at wherever the oil is on the new dipstick.

 

I used a Ratio-Rite cup , (we used to race motocross) ,,and measured out exactly 4 quarts in an old windshield washer jug .
I marked each quart level on that jug,,,,and had 4 graduated lines .
I never used it for a SBC,,,but I checked my DeSoto pan .
The level for 5 quarts was exactly 4.5 inches below the pan rail,,,,,with the pan sitting at approximately the same level as installed in a vehicle.
That is approximately 2 inches below the crank counterweights,,,and well below my windage tray studs .
I’m anticipating running 6 quarts in the pan and 1 in the filter,,,plenty of room there for the oil to clear everything .

Tommy

 

I took the original dipstick & tube off a stock engine and used them for the initial fill on my last couple engines. Then used that level to mark the aftermarket dipsticks I was using. Seemed logical to me.

The way that aluminum pan slants so low at the back edge looks like an invitation to catch the drain plug on something.