[tekuhn]

I'm building an engine that the factory (1970) oil pan has been deepened by 2 inches. I'm pretty sure that increases the capacity by a couple of quarts, or more. Would it make sense to take advantage of this to run more oil, or to lower the static oil level to reduce windage? Or perhaps something in between such as run 1 additional quart of oil and lower the level? This engine will not be raced except for an occasional street or strip blast, with the periodic rip through the gears on a country back road the more common. The pump pickup has, of course, been lowered to match the new sump depth.

[Mister Pontiac]

Since you're talking about street/limited strip use, I'd say just run the stock level. The problem is that the dipstick will not indicate correctly anymore. You may need to remark it (if it even touches the oil anymore) to indicate properly. Either that or run one extra quart, and that should put the true "Full" level around the 1 Qt low mark.

Hope that helps.

[grandam1979]

I would add the extra oil that you did the pan work for.

[tekuhn]

Originally Posted by Mister Pontiac

Since you're talking about street/limited strip use, I'd say just run the stock level. The problem is that the dipstick will not indicate correctly anymore. You may need to remark it (if it even touches the oil anymore) to indicate properly. Either that or run one extra quart, and that should put the true "Full" level around the 1 Qt low mark.

Hope that helps.

It sounds like you're actually saying to run the stock volume which would be off the stick. I will be making a custom upper dipstick tube and making a new dipstick from one of the long A/C equipped units, so remarking at a longer length would not be a problem. Thanks for your input.

[PontiacJim1959]

I am extending my '73 oil pan (which has the oil pan baffle) right now. I also added a rear baffle to the pan. I would fill the pan (if it is still out) with 5 Qts of food colored water and see where the level is at and try to figure about where it will set above the oil pick-up. Then add 1 more quart (for a total of 6 quarts) and see how much the level increases. I plan on doing this with my pan and will decide how many quarts I want to keep the level at.

For the street, 6 quarts should be OK. But remember, more oil means it takes longer to heat up the oil and extra oil can also hold in heat. So when you fire up the car, I would let it idle a bit to get some heat into the oil so the oil flows.

Check your ground clearance as well.

[tekuhn]

Originally Posted by grandam1979

I would add the extra oil that you did the pan work for.

The pan was already deepened when I bought the engine, but no dipstick was provided, so it's up to me to decide how to take advantage of it. Right now I'm leaning toward adding some additional oil and also lowering the stock level slightly. The modifications to the pan also included brazing some small baffles in it.

I need to add measured quarts of water in the pan to see where the level sits at say 6, 7, and 8 quarts.

[tekuhn]

Originally Posted by PontiacJim1959

I am extending my '73 oil pan (which has the oil pan baffle) right now. I also added a rear baffle to the pan. I would fill the pan (if it is still out) with 5 Qts of food colored water and see where the level is at and try to figure about where it will set above the oil pick-up. Then add 1 more quart (for a total of 6 quarts) and see how much the level increases. I plan on doing this with my pan and will decide how many quarts I want to keep the level at.

For the street, 6 quarts should be OK. But remember, more oil means it takes longer to heat up the oil and extra oil can also hold in heat. So when you fire up the car, I would let it idle a bit to get some heat into the oil so the oil flows.

Check your ground clearance as well.

Nice work! In a '70 GTO, my clearance won't be great, but the mods were done by Leader Automotive in 1970 (quite possibly by George DeLorean - who knows?), and I'd like to keep the mods if I can.

[69gtocv]

I don't have an oil pan to measure, but say the piece you added is 8"x8"x2", then the volume to fill that would be just a tad over 2 quarts

[PontiacJim1959]

Originally Posted by tekuhn

Nice work! In a '70 GTO, my clearance won't be great, but the mods were done by Leader Automotive in 1970 (quite possibly by George DeLorean - who knows?), and I'd like to keep the mods if I can.

Thanks. My pan drop is not as neat as I don't have anything other than a piece of round tubing to form the corners around, so I had to make it in several sections. Just got the last piece fitted and tack welded and now it is ready to be welded up solid.

A ton of work and it would have been much easier to buy an aftermarket pan. But, I wanted to do "old school" and figured if I screwed up, then go aftermarket.

I Used a Moroso extended oil pickup and then got my clearance from the bottom of the sump pan section and bottom of the screen and that gave me how much I needed to extend the sump. You can see the stacks of fender washers under the screen - the pick screen is angled and I adjusted so as to get a level pan bottom.

I don't know when Milt Scornack left Leader, but he did the pan extension on earlier GTO's that got the Royal treatment for SS racing. I posted a photo I have posted here before and you will see it looks like yours. Check out that oil pump set-up.

[tekuhn]

Originally Posted by PontiacJim1959

I don't know when Milt Scornack left Leader, but he did the pan extension on earlier GTO's that got the Royal treatment for SS racing. I posted a photo I have posted here before and you will see it looks like yours. Check out that oil pump set-up.

I wondered the same, but the bio I found on him said he left Leader in 1963 to go to Royal Pontiac. When Royal closed it's performance service business in late '69, he started Royal Automotive.

[FrankieT/A]

An original oil holds 5 quarts plus the filter, 6 quarts for a Pontiac. Me, personally would run the proper dipstick for your engine application. If your pan has been deepened by 2 inches and ground clearance is not a problem, it should take an extra 2 quarts approximately. About a quart per inch on a Pontiac pan.

Think about this for a second, your crank and connecting rod journals are cooled exclusively by oil. The more oil you have on reserve the more heat your oil can remove from the main and rod bearings. You will find your engine will run cooler with more oil. Again using the proper dipstick which has nothing to do with the pan, fill your oil to the full mark and figure out exactly how much extra oil you need. It would be no worse from a windage standpoint than a stock set up. On a engine cooling note, you shouldn't be running 20w50 weight oil either unless your bearing clearances are widened to accommodate thicker oil. People like to see high oil pressure so they use 20/50 to make themselves feel better, but actually what happens is "Yes" the pressure is high but you have drastically slowed down the oil flow and thereby have slowed the heat dissipation. Oil IS a part of the cooling system indirectly. More oil capacity more cooling!!! And trust me your oil will get to normal oil operating temp as long as you use a thermostat.

[tekuhn]

Originally Posted by FrankieT/A

An original oil holds 5 quarts plus the filter, 6 quarts for a Pontiac. Me, personally would run the proper dipstick for your engine application. If your pan has been deepened by 2 inches and ground clearance is not a problem, it should take an extra 2 quarts approximately. About a quart per inch on a Pontiac pan.

There is no complete dipstick for my application. I will need to fabricate the upper dipstick tube and attachment bracket and then cut a dipstick to length. I plan to mark the various quart levels in the pan and then measure where the "stock" location is and adjust from there. I'm still leaning toward lowering the level slightly. If I can have 7 quarts of oil, I'll be happy.