This was the first system on the G54 in my colt.
Anone have information regaurding making a dry sump oil pan?
Moderators: DJpowerHaus, mattmartindrift
I have a few minutes,
A dry sump oil pan should be as deep with as much volume inside it as possible.
There are two main reasons for this,
It has to allow the cross cylinder breathing, as one piston is coming down the air needs to go over to a cylinder that the piston is going up.
The oil can not be told where to go, you need to let it get out of the moving mass and settle where it chooses. This is where you put the pickups.
Obviously the depth has limits due to the height of the engine in the chassis. This is determined buy many variables as flywheel diameter, transmission depth below crank center and from structure that may need to be under the engine.
We can adjust the diameter of the flywheel, the reduction of diameter is only limited by money.
If we are working with production gearboxes, the cluster gear is under the mainshaft. Race boxes the cluster is off to the side. VW and Porches we flip the box over, easy since they have remote shifters and we want to get the diff up over the crank center. The later Porsches use a pressure oil system so it gets a change to work with the inverted box.
There is no reason we can not flip a production RWD box, it takes work to the shifter and a rethink on the internal oil system. They are generally splash systems.
Then if we can reduce what needs to pass under the engine, steering, crossmember, etc. we can then get the engine nice and low to make a real tough oil pan to design.
A dry sump oil pan should be as deep with as much volume inside it as possible.
There are two main reasons for this,
It has to allow the cross cylinder breathing, as one piston is coming down the air needs to go over to a cylinder that the piston is going up.
The oil can not be told where to go, you need to let it get out of the moving mass and settle where it chooses. This is where you put the pickups.
Obviously the depth has limits due to the height of the engine in the chassis. This is determined buy many variables as flywheel diameter, transmission depth below crank center and from structure that may need to be under the engine.
We can adjust the diameter of the flywheel, the reduction of diameter is only limited by money.
If we are working with production gearboxes, the cluster gear is under the mainshaft. Race boxes the cluster is off to the side. VW and Porches we flip the box over, easy since they have remote shifters and we want to get the diff up over the crank center. The later Porsches use a pressure oil system so it gets a change to work with the inverted box.
There is no reason we can not flip a production RWD box, it takes work to the shifter and a rethink on the internal oil system. They are generally splash systems.
Then if we can reduce what needs to pass under the engine, steering, crossmember, etc. we can then get the engine nice and low to make a real tough oil pan to design.
The system in my car is a tall 6" dia. tank. Two scavenge sections with single 3/4 aluminum tubes to and from the tank in the back of the car.
This car used a Weaver pump sized for a small block.
I like the tank to be as tall as the section of car it goes in, I only run 5-6 quarts in the tank, the rest is air space.
I am doing a Lotus at this time with a 3 section scavange with the third pulling from up on the head.
This car used a Weaver pump sized for a small block.
I like the tank to be as tall as the section of car it goes in, I only run 5-6 quarts in the tank, the rest is air space.
I am doing a Lotus at this time with a 3 section scavange with the third pulling from up on the head.
-
Robert Venable
- Donating Member
- Posts: 229
- Joined: Fri Sep 22, 2006 8:37 pm
- Location: BATON ROUGE, LA
My understanding of dry sumps is that there is normally multiple scavenge pumps with a single supply pump, unless you have an engine that is mounted at an unusual angle. The Scavenge lines are always larger than the supply lines also.
OLD COLT:
What is the need for all of the air space in the tank?? Why only 5-6 quarts? Wouldn't a larger quantity of oil allow for the oil to sit longer to cool and drop junk out of suspension (kinda a gravitational oil filter)???
OLD COLT:
What is the need for all of the air space in the tank?? Why only 5-6 quarts? Wouldn't a larger quantity of oil allow for the oil to sit longer to cool and drop junk out of suspension (kinda a gravitational oil filter)???
1990 MIGHTY MAX, REG CAB,
Correct on the scavenge pump, on small engines generally 2 -3 scavenge sections are used. The big engines are now using up to 5 scavenge pulling from each head, the valley and from the sump.
I had gone to the dry sump since the old single cam Mitsus drain the back of the head at the drivers rear and the chaincase up front. In a long left turn the head retained enough oil that I would scuff a bearing. When life was simple in the 70s I ran events three weekends a month and pulled the engine on my off week to check the rod bearings. Back then it took me 2 hours to pull the engine, roll it over go inside and the put it back together and installed again. Heck with the little G32 engine I did not use a lift, I wrestled it in and out by hand.
Well then I put in the G54, you can't pick that engine up alone and it took many hours to get in and out. I did not want to do bearing checks anymore.
So now it is drysumped.
With all drysump pumps except the AutoVerdi there is allot of suspended air in the return oil. The tank is tall and round so we can spray the return against the upper wall and let the bubbles settle out.
This allows a more liquid oil to settle for the return to the pressure side of the pump to feed the engine with.
The Autoverdi uses an integral air oil separator and two returns, one liquid and the other for air to the tank.
The 5 -6 quarts in the tank is only a portion of what is in the system, the lines, filter and cooler will have 3 -4 more and the engine generally has 3 or so quarts in it still.
The filter should be all that is needed for catching any debris and the cooler will do its job.
Most installs also run a vent from the top of the tank to the engine. If the engine, rings in particular are well sealed they do not connect the two and this draws a vacuum within the engine.
I had gone to the dry sump since the old single cam Mitsus drain the back of the head at the drivers rear and the chaincase up front. In a long left turn the head retained enough oil that I would scuff a bearing. When life was simple in the 70s I ran events three weekends a month and pulled the engine on my off week to check the rod bearings. Back then it took me 2 hours to pull the engine, roll it over go inside and the put it back together and installed again. Heck with the little G32 engine I did not use a lift, I wrestled it in and out by hand.
Well then I put in the G54, you can't pick that engine up alone and it took many hours to get in and out. I did not want to do bearing checks anymore.
So now it is drysumped.
With all drysump pumps except the AutoVerdi there is allot of suspended air in the return oil. The tank is tall and round so we can spray the return against the upper wall and let the bubbles settle out.
This allows a more liquid oil to settle for the return to the pressure side of the pump to feed the engine with.
The Autoverdi uses an integral air oil separator and two returns, one liquid and the other for air to the tank.
The 5 -6 quarts in the tank is only a portion of what is in the system, the lines, filter and cooler will have 3 -4 more and the engine generally has 3 or so quarts in it still.
The filter should be all that is needed for catching any debris and the cooler will do its job.
Most installs also run a vent from the top of the tank to the engine. If the engine, rings in particular are well sealed they do not connect the two and this draws a vacuum within the engine.
-
Robert Venable
- Donating Member
- Posts: 229
- Joined: Fri Sep 22, 2006 8:37 pm
- Location: BATON ROUGE, LA
Many times the scavenge pump is not happy with coolers or filter in there lines. You do want a screen before the scavenge but that is to reduce pump damage when an engine makes chips.
I did run a cooler in my scavenge but it was a system I built 22 years ago, I have learned since then coolers, filters heat exchanger go in the pressure side.
On the G54 oil goes in the filter boss. The pipe plug at the back was a bit tough to get to and this engine has the least oil system problems. Don't count in Chrysler's lack of nitriding parts here.
The 6G7 series the front left on the block has a 3/8 pipe fitting that is used.
A G6x I use a machine plate replacing the filter mount.
On the G6x series I want to find a different cam belt so as to eliminate the pump pulley completely. This will allow much more wrap around the crank gear greatly lowering the tooth load on the belt.
I did run a cooler in my scavenge but it was a system I built 22 years ago, I have learned since then coolers, filters heat exchanger go in the pressure side.
On the G54 oil goes in the filter boss. The pipe plug at the back was a bit tough to get to and this engine has the least oil system problems. Don't count in Chrysler's lack of nitriding parts here.
The 6G7 series the front left on the block has a 3/8 pipe fitting that is used.
A G6x I use a machine plate replacing the filter mount.
On the G6x series I want to find a different cam belt so as to eliminate the pump pulley completely. This will allow much more wrap around the crank gear greatly lowering the tooth load on the belt.
-
Robert Venable
- Donating Member
- Posts: 229
- Joined: Fri Sep 22, 2006 8:37 pm
- Location: BATON ROUGE, LA
When you do, let us know.Old Colt wrote:A G6x I use a machine plate replacing the filter mount.
On the G6x series I want to find a different cam belt so as to eliminate the pump pulley completely. This will allow much more wrap around the crank gear greatly lowering the tooth load on the belt.
What, IYO, do you feel are the down sides of running a drysump system?
What, IYO, are the down sides of running a drysump system on the street?
1990 MIGHTY MAX, REG CAB,
A dry sump adds cost and complexity.
On the street I just pay attention to the warmup of the engine. To me this should be done anyway especially with anything making a bunch of power. When we used to run straight 50 weight oil this was very important with the long suction line to the pump. Todays light oils it is less of a concern as far as the oil system goes.
If the drysump is needed for a reason then there are no issues, it doe's it's job.
The Lotus I am building we budgeted about $ 3K for the drysump system. The car was going through two engines a year, each time he got over 7000 rpm it lost oil pressure. This was on straights, not just cornering.
I got started on the build and once he brought me and engine and his old oil sump and windage tray I found two big problems. The biggest was the engine had a windage tray with flapper doors to direct the oil to the pickup. Cool. But there was only one way for the oil to get under the tray and that was at the small opening for the pickup. When the engine was up at high revs the oil would load up on top of the tray right in the crankshaft. The flappers do there job but the oil was not allowed into the chambers below the tray.
The second issue is that with the Renault engine the rod bearings are about 20 mm wide. This is fine for a tractor but at high revs they do not tolerate crank flex and are prone to not keeping an even oil film to the outer edges. Simply narrowing the bearing surface cures this.
His engine builder put a groove around the center of the rod shells, this actually lowers the film pressure rather than raise it since it gives the oil a place to be squished into.
To me I am now building this dry sump for little reason since the problems have been found. But the customer loves the glitter of the stainless hoses so the system is going in.
I will turn the oil pressure up stupid high to try to keep his rods in there.
Wrong way to fix something IMO.
On the street I just pay attention to the warmup of the engine. To me this should be done anyway especially with anything making a bunch of power. When we used to run straight 50 weight oil this was very important with the long suction line to the pump. Todays light oils it is less of a concern as far as the oil system goes.
If the drysump is needed for a reason then there are no issues, it doe's it's job.
The Lotus I am building we budgeted about $ 3K for the drysump system. The car was going through two engines a year, each time he got over 7000 rpm it lost oil pressure. This was on straights, not just cornering.
I got started on the build and once he brought me and engine and his old oil sump and windage tray I found two big problems. The biggest was the engine had a windage tray with flapper doors to direct the oil to the pickup. Cool. But there was only one way for the oil to get under the tray and that was at the small opening for the pickup. When the engine was up at high revs the oil would load up on top of the tray right in the crankshaft. The flappers do there job but the oil was not allowed into the chambers below the tray.
The second issue is that with the Renault engine the rod bearings are about 20 mm wide. This is fine for a tractor but at high revs they do not tolerate crank flex and are prone to not keeping an even oil film to the outer edges. Simply narrowing the bearing surface cures this.
His engine builder put a groove around the center of the rod shells, this actually lowers the film pressure rather than raise it since it gives the oil a place to be squished into.
To me I am now building this dry sump for little reason since the problems have been found. But the customer loves the glitter of the stainless hoses so the system is going in.
I will turn the oil pressure up stupid high to try to keep his rods in there.
Wrong way to fix something IMO.
-
DJpowerHaus
- Sir Post A Lot
- Posts: 1782
- Joined: Wed Apr 07, 2004 3:24 pm
- Location: Baltimore, MD
- Contact:
I have been running both lightened stock pulleys as well as aluminum ones. I have not seen any ill effects with any of the Mitsu engines running light pulleys and flywheels. I expect there must be somewhere in the rpm band where each engine has a nasty harmonic.
The latest EVOs have damped alloy pulleys.
We all can feel some roughness from each type of engine but say the 2200 rpm shake in a Staron, Is it critical? I do not think so. When I drive a Starion I don't take it much over 2K till top gear when driving easy. Driving hard I run 8K+.
I also do not like a G63 running under 2K. They just feel like they want to beat there bearings out. Also most G63 belt failures are right about 2000 rpm. Defiantly a harmonic there since it takes out belts, but will it take out a crank? I don't think so.
I do not know if the High power G64 crank failures are due to a harmonic or just the limit of the crank. In the 800+ HP engines I have heard of failing they have been the cast cranks. There might be failures of the forged ones that I am not aware of. And then the question, harmonic related failure or just the material limit, maybe 100 +mm stroke engines do not like 10K + revs.
I do like to run the lightest pulley and flywheel combination I can afford.
In the world of vintage racing with the 3 bearing MG engines, these old lumps really needed there dampers. But now the engines get built with the lightest parts, rods, flywheels etc and they live at stupid high revs that were unheard of twenty years ago.
The latest EVOs have damped alloy pulleys.
We all can feel some roughness from each type of engine but say the 2200 rpm shake in a Staron, Is it critical? I do not think so. When I drive a Starion I don't take it much over 2K till top gear when driving easy. Driving hard I run 8K+.
I also do not like a G63 running under 2K. They just feel like they want to beat there bearings out. Also most G63 belt failures are right about 2000 rpm. Defiantly a harmonic there since it takes out belts, but will it take out a crank? I don't think so.
I do not know if the High power G64 crank failures are due to a harmonic or just the limit of the crank. In the 800+ HP engines I have heard of failing they have been the cast cranks. There might be failures of the forged ones that I am not aware of. And then the question, harmonic related failure or just the material limit, maybe 100 +mm stroke engines do not like 10K + revs.
I do like to run the lightest pulley and flywheel combination I can afford.
In the world of vintage racing with the 3 bearing MG engines, these old lumps really needed there dampers. But now the engines get built with the lightest parts, rods, flywheels etc and they live at stupid high revs that were unheard of twenty years ago.
-
Robert Venable
- Donating Member
- Posts: 229
- Joined: Fri Sep 22, 2006 8:37 pm
- Location: BATON ROUGE, LA
I totally aggree on stuid high oil pres. I've seen the effects on lower end bearings when running past 70ish psi of oil pres. After a while, the bearings simply wash the babbit out.
I think it was GM that came up with the 7 psi per 1000 rpm(anyone know?), and I totally aggree with it. Everytime someone brags about how they can peg out there 100 psi Oil pres. guage I cringe.
I also feel that everyone that goes the extra mile to instal HO oil pumps are simply killing power for no reason(mostly the Domestic V8 world).
I personally preffer high volumes with slightly less restriction to keep oil pres. about stock (assuming you have not opened up the clearances excessivly).
I think it was GM that came up with the 7 psi per 1000 rpm(anyone know?), and I totally aggree with it. Everytime someone brags about how they can peg out there 100 psi Oil pres. guage I cringe.
I also feel that everyone that goes the extra mile to instal HO oil pumps are simply killing power for no reason(mostly the Domestic V8 world).
I personally preffer high volumes with slightly less restriction to keep oil pres. about stock (assuming you have not opened up the clearances excessivly).
1990 MIGHTY MAX, REG CAB,