• Sign Up! To view all forums and unlock additional cool features

    Welcome to the #1 Explorer ST Forum and Explorer ST community dedicated to Explorer ST owners and enthusiasts. Register for an account, it's free and it's easy, so don't hesitate to join the Explorer ST Forum today!


What Breaks at what power levels?

TMac

1000 Post Club
Messages
1,692
Reactions
1,451
Points
262
Location
Knoxville, TN
#21
That's a sobering thought.
You can bet there's some engineering leeway built into the torque spec. And it's a static measure, so if you locked the output shaft in a vise (for example), and started twisting the input shaft with a really, really long torque wrench, theoretically something would go "pop". But that's not a likely scenario, except for a violent launch and even then, there's probably 20% or more leeway built in to the spec. If someone were actually thinking about a world record drag racing platform, well...I mean come on. Despite the little niggles here and there, this is a very well engineered platform IMHO.
 

Messages
279
Reactions
456
Points
67
Location
Marinette, WI, USA
#22
Motor development is in process! Hang in there guys this stuff isn't easy to get these days!


Sent from my SM-N986U using Tapatalk
 

TMac

1000 Post Club
Messages
1,692
Reactions
1,451
Points
262
Location
Knoxville, TN
#23
Thanks for sharing those pics with us, I'm looking forward to seeing more! In relation to your post on oil starvation at launch. Could you please post pics of the pan, pump, and pickup? From what I have read, the variable oil pump is driven off the front of the crank. Which would suggest the pickup is also located in that area which would explain the oil moving to rear of the pan and away from the pickup under hard acceleration.

In a metal pan, there would be vertical baffles with smaller slots or holes in the bottom of the each baffle. This design restricts the the bulk of the oil from moving away from the pickup while allowing its eventual return to the pickup via the slots. It occurs to me that since the pan seems to be injection molded plastic and baffling with return orifices would be hard to achieve in an investment mold. Is that the problem?
 

Messages
279
Reactions
456
Points
67
Location
Marinette, WI, USA
#24
Thanks for sharing those pics with us, I'm looking forward to seeing more! In relation to your post on oil starvation at launch. Could you please post pics of the pan, pump, and pickup? From what I have read, the variable oil pump is driven off the front of the crank. Which would suggest the pickup is also located in that area which would explain the oil moving to rear of the pan and away from the pickup under hard acceleration.

In a metal pan, there would be vertical baffles with smaller slots or holes in the bottom of the each baffle. This design restricts the the bulk of the oil from moving away from the pickup while allowing its eventual return to the pickup via the slots. It occurs to me that since the pan seems to be injection molded plastic and baffling with return orifices would be hard to achieve in an investment mold. Is that the problem?
You can see the pan in the full motor picture isn't really a pan per say. The oil is really in the lower block the pan is more of a tray.



Sent from my SM-N986U using Tapatalk
 

TMac

1000 Post Club
Messages
1,692
Reactions
1,451
Points
262
Location
Knoxville, TN
#25
Interesting. It would certainly appear that the cross webbing would do an adequate job of baffling the oil movement while the "tray" would allow adequate clearance to drain back to the pump. So much for the injection molding casting being the source of the baffling. But seeing this, I don't see a problem of g-force necessarily being a problem for oil starvation. Might this instead be a head drainback issue? I'm assuming the semi-rectangular area to the right of the pickup in the pick is the passenger head drainback?

Once again, thanks so much for the pics.
 

zdubyadubya

Active Member
Messages
813
Reactions
631
Points
232
Location
Utah
Vehicle
2020 ST
#26
Those pics explain sooooooo much why the pan is plastic. Its actually a really clever design (building the pan/sump into the block). I agree... the baffles look good to me as well.
 

Messages
279
Reactions
456
Points
67
Location
Marinette, WI, USA
#27
Interesting. It would certainly appear that the cross webbing would do an adequate job of baffling the oil movement while the "tray" would allow adequate clearance to drain back to the pump. So much for the injection molding casting being the source of the baffling. But seeing this, I don't see a problem of g-force necessarily being a problem for oil starvation. Might this instead be a head drainback issue? I'm assuming the semi-rectangular area to the right of the pickup in the pick is the passenger head drainback?

Once again, thanks so much for the pics.
Definitely from the g-force of the launch all the oil is in the pan right before lunch and the only issue it has it's right at launch. If it was a drain back issues it would happen down track .


Sent from my SM-N986U using Tapatalk
 

Last edited:

TMac

1000 Post Club
Messages
1,692
Reactions
1,451
Points
262
Location
Knoxville, TN
#28
Definitely from the g-force of the launch all the oil is in the pan right before lunch and the only issue it has it's right at launch. If it was a drain back issues it would happen down track .


Sent from my SM-N986U using Tapatalk
After giving it some thought, I'm thinking the next possible culprit would be a volume issue. Hear me out, in the area directly around the pickup between the webs and assuming the oil level is below the crank, it certainly seems that there isn't room for more than (maybe) a quart or less of oil in that area. So, I'd ask you this- are you able to look at the duty cycle of the variable oil pump? For example, if when throttle demand goes 100% in the "launch" circumstance, does the ecu activate maximum oil pressure/volume? If so, you might be able to back down the duty cycle of the variable solenoid. While it might seem counter-intuitive, it's likely that the engineers would err on the side of max flow. If you can control this, you might be able to back down the volume required and not starve the engine.
 

Messages
279
Reactions
456
Points
67
Location
Marinette, WI, USA
#29
After giving it some thought, I'm thinking the next possible culprit would be a volume issue. Hear me out, in the area directly around the pickup between the webs and assuming the oil level is below the crank, it certainly seems that there isn't room for more than (maybe) a quart or less of oil in that area. So, I'd ask you this- are you able to look at the duty cycle of the variable oil pump? For example, if when throttle demand goes 100% in the "launch" circumstance, does the ecu activate maximum oil pressure/volume? If so, you might be able to back down the duty cycle of the variable solenoid. While it might seem counter-intuitive, it's likely that the engineers would err on the side of max flow. If you can control this, you might be able to back down the volume required and not starve the engine.
It's already in high volume mode on the brake boost. And they don't have issues if you brake boost during a second gear roll. So I don't think it's a volume issue.The webing doesn't touch the pan so while may help there is plenty of room for it to slosh out. It's very common for these to pull 1-1.2g on launch plus you have to consider how much the front is coming up and how much pitch there really is during the launch.

If you look at F-150 Market 3.5 liter is a completely different configuration it still has the same issue because pickup is in the front of the sump much like is. And if you compare a Raptor to a regular F-150 the Raptor is much worse because of how much more it pitches back on a launch.

Sent from my SM-N986U using Tapatalk
 

OP
U
Messages
138
Reactions
60
Points
27
Location
The forrest
Thread Starter #30
Look at all that casting material behind the valve seat...plenty of cleanup could be done there if the head will allow it...This is good info, Thanks
 

TMac

1000 Post Club
Messages
1,692
Reactions
1,451
Points
262
Location
Knoxville, TN
#31
It's already in high volume mode on the brake boost. And they don't have issues if you brake boost during a second gear roll. So I don't think it's a volume issue.The webing doesn't touch the pan so while may help there is plenty of room for it to slosh out. It's very common for these to pull 1-1.2g on launch plus you have to consider how much the front is coming up and how much pitch there really is during the launch.

If you look at F-150 Market 3.5 liter is a completely different configuration it still has the same issue because pickup is in the front of the sump much like is. And if you compare a Raptor to a regular F-150 the Raptor is much worse because of how much more it pitches back on a launch.

Sent from my SM-N986U using Tapatalk
So, are are saying the pan is far enough below the webbing that the baffling provided is insufficient? I certainly get that due to the front end lift and g force, there would be much more effect on oil flowing away from the pickup. As a follow up, do I understand that the oil pump is pretty much binary, or high low, and not driven by a duty cycle solenoid? Assuming it's variable, I was proposing that perhaps dropping it down a bit might work, but if it's truly a baffling issue, that wouldn't work obviously and would require some other type of mechanical baffling solution. Perhaps extending the webbing deeper into the tray?

If it the pump duty cycle is variable, it would still be interesting to see that duty cycle mapped against the pressure drop on a launch similar to the graph you shared. By the way, I'm impressed. You're far more knowledgeable than just some "tuning" guy.
 

Last edited:
OP
U
Messages
138
Reactions
60
Points
27
Location
The forrest
Thread Starter #32
Whats the story on the the steel line going into the oil pump after the pickup tube? It looks like it runs to/from the front of the block next to the crank down to/from the oil pump. Is it a bypass valve/line or some sort of return line?
 

TMac

1000 Post Club
Messages
1,692
Reactions
1,451
Points
262
Location
Knoxville, TN
#33
Whats the story on the the steel line going into the oil pump after the pickup tube? It looks like it runs to/from the front of the block next to the crank down to/from the oil pump. Is it a bypass valve/line or some sort of return line?
I'm curious about that too. Return from the chain tensioners? I'm sure zfg will let us know.
 

F=MA

Active Member
Messages
903
Reactions
577
Points
232
Location
Wichita, KS, USA
#34
Do you have a log showing the oil pressure with the oil level 1/2 quart above full? I sent a message to Canton Racing about the use of an Accusump oil accumulator kit that would maintain oil pressure at startup and cover for these moments of low oil pressure. I believe Kevin (Kruppa) has one on his ST.
 

Last edited:
OP
U
Messages
138
Reactions
60
Points
27
Location
The forrest
Thread Starter #35
Answered my own question. It is listed as a oil return tube
 

LokiWolf

Active Member
Messages
580
Reactions
315
Points
182
Location
Henrico, VA
#36
Do you have a log showing the oil pressure with the oil level 1/2 quart above full? I sent a message to Canton Racing about the use of an Accusump oil accumulator kit that would maintain oil pressure at startup and cover for these moments of low oil pressure. I believe Kevin (Kruppa) has one on his ST.
Yes. I would have to dig them off my laptop.

Adam@ZFG and I did MANY nights of logging on the oil issue at launch in early 2020, while we were working on the launch on the 93 tune, and then the E50 tune.

He saw the dips/zero pressure in the logs. Discovered I was low fill from the factory, so remedied that. We still saw the dips in the logs, not as long or as low, but still there. Over filled about a 1/4, still saw dips, again less. Put it to 1/2 over and we were good to go, never saw the dips again.

If you are regularly launching the ST hard, especially on E50, and with stock suspension, I recommend 1/4-1/2 over as a little insurance.


Sent from my iPhone using Tapatalk
 

F=MA

Active Member
Messages
903
Reactions
577
Points
232
Location
Wichita, KS, USA
#37
Great info. I have the H&R springs so I believe there is less front end lift on launch compared to the OEM springs. I will have to look back and see if I had the E50 tune before the spring replacement. I think it was so that may play into the low pressure Adam was seeing on mine also.
 



Top