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· L&M Engines
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While I'm on the crank snout topic, here is photos of a 5.0 oil pump that was fractured by the crankshaft acceleration and the out of phase blower drive acceleration.

This failure is not isolated to blower folks, N/A folks suffer from this with less degree, but it occurs.
The N/A guys will see this more on a manual transmission car due to the hole shot and gear shift causing high rates of crankshaft positive and negative acceleration.
 

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I've heard that they're coming out with a stronger gearset for the oil pump, but that seems like a bass-ackwards fix. What's the best-case fix for this? I understand how you said that N/A cars sometimes experience this, but as a rule, will this failure occur primarily on boosted motors when running north of 12psi when subjected to high-rpm launches and 7k+ gear changes? Thanks
 

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boosted?

Just conjecture, but a boosted motor would actually have the same or less shock to the gears due to converter slippage or clutch slippage. Other than that, rpm equals momentum and it rises by the square of the rpm. Raise the rpm 10 percent, you get 21 percent more shock load. Cold oil would be another big culprit, if the viscosity is higher than when fully warm. Detonation certainly wouldn't help either.
A fully warmed motor with an auto trans equipped with a loose converter would be the best scenario.
 

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Michael, after reading your post, the first thing that popped into my head was that the producers of Mad Max (the blower with the electric clutch) had it right, lol. Maybe someone needs to design a one way clutch/pulley combo like Ford uses on its alternators?


Tim
 

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It is certainly possible if you had all the information to support that.

My claim is very easily read in the first post.
Ive seen oil pumps fail exactly like this for almost 10 years now and every time it was from detonation.

The pump gear is moving in one direction; detonation occurs and pushes backward on the crank for a moment..... gears collide and poof they go.
Ive never heard your theory before, although I guess its possible.
 

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I agree pump failures were seen that appeared to be like this 10 years ago, mainly 4V engines seeing some RPM. Now, lets think about a few things that have changed, placing more cycles with more force onto the crank.

1.That big heavy dual sheave damper wasn't hanging on the snout.
2.The blowers of that time were small, the baddest around was a Novi 2000, how big does that sound to you now? Way less loading through the belt to drive those.
3.When the Lightning came out 13 model years ago with an M112 on just a 5500 RPM engine, Ford thought it needed a crank support bad enough to spend the money on one, and continued this with the 03 Cobra. Now this is somehow unimportant with these far bigger blowers?
4.RPM, now they're all turning north of 7K.
5.Gears, we now have more of them, so more WOT gear changes.

Given the above facts, how can the crank snout not be moving around more, and doing it more often?
you are correct about all the points you just made..... but you haven't noted the changes that ford has made after the lightning and cobras that were implemented on the shelby's and 2011-2012 5.0's.

The lightnings and cobras had crankshafts that were taken directly from production cars and installed on supercharged engines without any change to crank design (therefore the need for the support). on the shelby the cranks were pretty much the same but they made a key change to the dampner bolt by counterboring the crankshafts and allowing the bolt to reach #1 main journal to get rid of the deflection that was causing cranks to break snouts at the oil pump drive flange. how many shelby's are out there with crank supports? it's still not perfect and they do still break but it was a good change.

Now the coyote has the same design and has an added benefit when they moved the crank sensor to the rear of the engine. What they accomplished there was the ability of moving the dampner closer the #1 main and reducing deflection once again, it's not much but it is closer. There's alot of small changes on the coyote's but they all help these motors live at higher rpms.
 

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There where a few cobras that had this problem with the oil gears when they went to the tighter tolerance billet gear sets. I remember people posting up about how they thought that it was caused by the harmonics of the crank shaft actually causing the metal of the oil gears to shatter.
 
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