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.
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What Breaks at what power levels?
- Thread starter UpinBst
- Start date
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?
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?
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.
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 .
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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.
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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.
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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.
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.
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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.
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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.
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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.
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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.
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My 2020 ST started knocking 2 days ago on morning cold start.
- Latest: ButchsExplorerST
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