LS 240 oil pan question

[sr vegas 240]

I purchase a cxracing oil pan for my ls swap but i just met someone local who told me that he would not recommend anything from cxracing. Hes on his 3rd junk yard ls in 5 years(boosted with accusump). To me seems like good odds lol should i proceed with this oil pan or try to get something bit more quality? Sikky? almost double the price? stock GTO oil pan? Thanks in advance

[afishysilvia]

I had my CX pan for a year or so no issues.

Plain and simple, LS’s have oiling issues when drifting or racing. Accusump or drysump and you will be fine.


Also...your buddy is using “Junkyard” motors lol...come on..

[SupaDoopa]

Accusump will save you in specific applications. This is if you've lost oil pressure for some reason [low oil at high G, hole in the pan, whatever]. It shouldn't really be used as a massive crutch like that. A good baffled pan with the proper pump and a safety net like Accusump [not necessary but nice to have] is the right formula. Most people go Canton pans with the baffles, a cooler that adds volume and Accusump.

A junkyard motor is only as good as the maintenance. If you're boosting the fucking thing to the moon and not really giving a shit about it, you'll be swapping motors pretty often.

One thing I do hear is sometimes an issue is pan-to-crossmember clearance. You obviously want the pan level with or above the crossmember in the instance you nose dive into some shit and you get smacked in the pan. There are ways to alter this as well.

[jr_ss]

This would be better off in tech...

[Kingtal0n]

If drag racing you want the sikky pan.

I don't know about the others but I can say for sure the sikky has trapdoors, kickout style pan, great ground clearance, good spots on both sides for turbo drain, and thanks to the trapdoors the oil stays where it needs to stay and never backs up in the oil drain.

Also my LM7 at 14.5psi makes 525/525 dynojet rwhp for 27,000 miles now, three years in a daily application, 93 octane only

If you know what you are doing the stock bottom ends are extremely reliable. Gota know the limit, how to tune, etc..
The LM7 in my car has over 200k and was $free from the scrapyard, partially because it was their worst looking, highest mileage... well you get the point.

[ovaloval]

If drag racing you want the sikky pan.

I don't know about the others but I can say for sure the sikky has trapdoors, kickout style pan, great ground clearance, 8 ball pool (https://8-ballpool.com/) game good spots on both sides for turbo drain, and thanks to the trapdoors the oil stays where it needs to stay and never backs up in the oil drain.

Also my LM7 at 14.5psi makes 525/525 dynojet rwhp for 27,000 miles now, three years in a daily application, 93 octane only

If you know what you are doing the stock bottom ends are extremely reliable. Gota know the limit, how to tune, etc..
The LM7 in my car has over 200k and was $free from the scrapyard, partially because it was their worst looking, highest mileage... well you get the point.

This is 93 octane only!

[DarkSlide77]

I had my CX pan for a year or so no issues.

Plain and simple, LS?s have oiling issues when drifting or racing. Accusump or drysump and you will be fine.


Also...your buddy is using ?Junkyard? motors lol...come on..


Do you think you could simulate a dry sump using a belt driven vacuum pump and an accusump?

[afishysilvia]

Do you think you could simulate a dry sump using a belt driven vacuum pump and an accusump?

Most certainly, but these are big steps. Have to ask OP what his goal is, if a street car then not worth it in my opinion. For a track car or something used solely for racing or hard driving then yes of course. The Oem Pan is designed well for ?Street? use, people often forget about doing these changes to essential but basic parts of the engine. They focus on clutch and other things which are needed but oil and lubrication is often overlooked.

[DarkSlide77]

Most certainly, but these are big steps. Have to ask OP what his goal is, if a street car then not worth it in my opinion. For a track car or something used solely for racing or hard driving then yes of course. The Oem Pan is designed well for ?Street? use, people often forget about doing these changes to essential but basic parts of the engine. They focus on clutch and other things which are needed but oil and lubrication is often overlooked.

Great info. I?ve always seen guys hook up the vacuum pump line to the valve cover on top..... question is..... can you mount it on the side of the oil pan? Something inside tells me I don?t want vacuum up top to mess with the oil flowing from the heads to the pan..I?d imagine it would be better to have the vacuum sucking from the bottom. Stupid ideas?
Idk if the vacuum pump would be effected by the potential extra amount of oil it could suck up from being on the side of the pan. What are your thoughts
Thanks

[Kingtal0n]

I think vacuum pumps are terrible idea for wet sump applications, it tends to dry out the wrist pins and reduces effective oil pressure

search "vacuum pump wrist pin" or "vacuum pump wet sump" something like that

[DarkSlide77]

I think vacuum pumps are terrible idea for wet sump applications, it tends to dry out the wrist pins and reduces effective oil pressure

search "vacuum pump wrist pin" or "vacuum pump wet sump" something like that

Thanks for telling me about this, super useful info. According to this race engine builder, this can happen even in a dry sump oiling system:eek: Guy in article says to increase clearance of the wrist pin. How else do people get around this, better oil pump or somethin?

Here?s what the article said-
?The crankcase in an engine with a conventional wet-sump oil pan is awash in oil. If there is a condition that?s heating up the wrist pins or stressing the piston and rod bores, the sheer volume of oil in the crankcase will carry off the excess heat. But a well-designed oil pan with a kick-out, crankshaft scraper and a vacuum pump (or a good dry-sump system) will dramatically reduce the amount of oil in the crankcase. While an efficient oil system reduces windage and increases horsepower, it can also put the wrist pins in jeopardy ? another instance of unintended consequences. In fact, the wrist pins in the even-numbered cylinders are often the first to show signs of distress caused by insufficient lubrication because they are on the side of the engine that has much of its lubrication stripped away by the crankshaft scraper and oil pan kickout.

In this situation, my recommendation is to increase the wrist pin clearance. Most engine manuals recommend wrist pin clearances between .0008 and .0010-inch for conventional engines; my advice is to run .0020 to .0022-inch wrist pin clearance in a serious drag racing engine. My perspective on engine clearances is straightforward: When in doubt, a little loose will seldom result in catastrophic failure, but a little too tight will almost always cause problems.?

[Kingtal0n]

I would just try to make a factory PCV setup work properly. Use the kickout style pan and crank scrapper to reduce windage but keep the pressure in the crankcase near atmospheric like 13psi vs the 14.5psi at sea level. I usually try to pull around 20 to 30" of H2O on the crankcase using dry paper air filter. This helps keep pressure off the seals, will prevent oil from blowing out of the engine, but is very mild in terms of vacuum. \


RPM can be a deal breaker so it depends what sort of racing you are doing. In the event 7200rpm+ (just guessing, it might not be an issue) is required and the oil becomes a problem I would modify the baffle in the valve cover directly (by cutting it open and adding a 'catch can' type of area to the valve cover or even by adding a regular sort of catch can device to control oil-overages, look at the sr20det 'oil/air separator' oil return type of device that feeds back to the oil pan for examples) and keep the pressure around OEM (13psi ish absolute if you are at sea level this is 1.5psi below atmospheric pressure) to protect wrist pins and oil pressure. Then an accumulator when setup proper can still be used to protect oil pressure in tough situations.

Another thing to consider is oil system modifications, such as piston oil squirters or porting of the oil orifices, smooth out and gasket matching type of stuff can help the oil reach places it would normally avoid. Like sometimes the grooves in an oil bore have 'lines' like in the barrel of a gun that shape the oil flow in a funny way, you can eliminate that or add some kind of structure to force it to flow around some areas that need it. When it comes to racing, its time to get creative, anything goes...

[DarkSlide77]

I would just try to make a factory PCV setup work properly. Use the kickout style pan and crank scrapper to reduce windage but keep the pressure in the crankcase near atmospheric like 13psi vs the 14.5psi at sea level. I usually try to pull around 20 to 30" of H2O on the crankcase using dry paper air filter. This helps keep pressure off the seals, will prevent oil from blowing out of the engine, but is very mild in terms of vacuum. \

RPM can be a deal breaker so it depends what sort of racing you are doing. In the event 7200rpm+ (just guessing, it might not be an issue) is required and the oil becomes a problem I would modify the baffle in the valve cover directly (by cutting it open and adding a 'catch can' type of area to the valve cover or even by adding a regular sort of catch can device to control oil-overages, look at the sr20det 'oil/air separator' oil return type of device that feeds back to the oil pan for examples) and keep the pressure around OEM (13psi ish absolute if you are at sea level this is 1.5psi below atmospheric pressure) to protect wrist pins and oil pressure. Then an accumulator when setup proper can still be used to protect oil pressure in tough situations.

Another thing to consider is oil system modifications, such as piston oil squirters or porting of the oil orifices, smooth out and gasket matching type of stuff can help the oil reach places it would normally avoid. Like sometimes the grooves in an oil bore have 'lines' like in the barrel of a gun that shape the oil flow in a funny way, you can eliminate that or add some kind of structure to force it to flow around some areas that need it. When it comes to racing, its time to get creative, anything goes...

Damn.... good shit. I have a kick out style oil pan (LS into s13 Sikky pan) so sounds like I?m good there. So-

1. Port oil squirt orifices
2. Play with the direction the oil squirts, try to hit pistons.
3. Have to research what gasket matching is, sounds self explanatory.
4. The 20-30? of H2O thing really lost me. Correct me if I?m wrong, but you?re saying you use one of those crank case ventilators that?s just a paper filter sticking out of the valve cover? So dont use the line that directs it back to the air intake?

Just did some research on all that pcv/baffle/oil catch can stuff. Really good shit I never knew I needed to know.

[Kingtal0n]

sorry confused you

1. I am not sure how or if the oil system in YOUR engine will support oil squirts. Or if its even possible. Was just pointing out the advantage of such things. let me know what you find.

2. do a search and get some result like this:
Inches of Mercury Inches of Water
0 inHg 0.00 in H20
1 inHg 13.60 in H20
2 inHg 27.19 in H20
3 inHg 40.79 in H20

A typical gauge from the car reads in Hg (mercury). So 15" of vacuum is really 15" of Mercury.
The crankcase should have some vacuum in it, relative to atmosphere.
Since atmosphere depends on altitude, I cannot quote some single value here. You have to use your own atmosphere.
For example, I am at sea level. So my atmosphere is 14.5psi.

Therefore, I want less than 14.5psi in the crankcase during idle/cruise/wot (at all times).
To get there, you must have some form of suction. The factory uses the intake manifold. Some people use venturi exhaust, some use a vacuum pump, belt or electric.
NEVER run an open breather. That is a huge mistake. It will lead to oil leaks, oil blowing out, oil seepage and damaged gaskets.

To measure how much vacuum you have in the crankcase, you need a gauge. A normal gauge is somewhat difficult to read because imagine trying to tell the difference between 2 and 1.5" of Hg on a gauge that reads up to 30". Its like you are only using 1/15 of the gauge, it doesn't make sense.

So instead, get a gauge (or a datalogger) that can read in Inches of Water. use the conversion above to see that 2" of Hg is really around 27Inches of Water. So a gauge that reads from 0 to 50 inches of water is ideal for the crankcase. It can measure very subtle changes in crankcase pressure.
The key to high performance engines... the most important thing of all IMO... it is the crankcase pressure. You must maintain at ALL TIMES a pressure of approx 15 to 35" of Water (around that, say 2" of Hg) inside the crankcase relative to your atmosphere (for wet sump applications)

Factory PCV achieves this two ways:
1. the pcv valve orifice flow is slightly higher than the fresh air vent flow at simultaneous pressure drop due to a calculated restriction in the fresh air vent orifice.

You should probably identify the fresh air inlet to the crankcase, and the pcv orifice before this will make any sense. SR20 actually have a restrictor that looks like a bronze plug with the hole in the center for this. LS engines simply use the diameter of the valve cover tube.

2. During WOT the factory uses a paper air filter to create a pressure drop behind the filter of approx 3" of Hg (pushing 40" of water) this is tied to the crankcase (this is the fresh air vent) and acts during WOT to provide that pressure drop.

FInally you should pressure test the crankcase once it is setup properly. Do this by simply blowing into the fresh air vent with your mouth and then checking to make sure the air doesn't leak out anywhere. It should hold air like a balloon, and then remove the dipstick and let the air out if you want to check the dipstick seal. The dipstick is part of the crankcase seal, along with valve cover and front/rear mains, just as important.
do not use a compressor because high pressure... will damage the oil seals. Only use 1-3psi MAX for this test if using a compressor.
Oh one more thing. Do not depend on the factory Chevrolet PCV valve if using boost. It will leak. Instead, run both the factory Chevy pcv valve in LINE with a Toyota Supra pcv valve. They are very cheap and effective.

[Kingtal0n]

Some images to help with pcv in wet sump apps

This one is IDLE/CRUISE situation (open pcv valve)
https://i.postimg.cc/wvVtLRZd/quickpcvdirty.png

Next showing CLOSED pcv valve (WOT)

https://i.postimg.cc/W3YMwK2y/basicpcv-WOT1.png

and again WOT

https://i.postimg.cc/JhF1McKX/pcv3.png

Finally showing the same exact thing but like a typical 4-cylinder for perspective
This one is Idle/Cruise situation (open pcv valve)
https://i.postimg.cc/GmT14hzm/checkme.gif