GT350 Engine Refresh Time!

[Strokerswild]

I believe its also best to store them in vertical position. That is probably for long term storage, just make sure they are coated and sealed up well and secured from falling, That would also put a major hurting on a toe!!

Correct, crankshafts should always stand on end vertically, long term.

Cylinder heads also.

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[firestarter2]

HB,

I’ve really enjoyed your build threads. I’m sympathetic to your attraction to doing the “overkill” shortblock treatment, but in this case I’d skip it... and I love overkill.

From my racing experience, the cost increase of a premium build gets you declining marginal benefit. And fast. That is, you’ll spend a lot to get a slight increase in engine life. There’s no doubt that this builder does great work, but you’ll be climbing the steep side of the “dollar per reliability increase” curve.

Good luck either way. You’re a madman in a good way.

This is my concern as well.

 

[AdamIsAdam]

Correct, crankshafts should always stand on end vertically, long term.

Cylinder heads also.

I understand the crank, by why the heads? If they are stored on a flat surface, then that's the same as being installed on the engine, no? And what is going to be deformed by horizontal storage?

Just curious, not challenging. I don't know the answer.

 

[AceOne]

There is one other improved part you might want to consider. M-6500-M50R Lash adjuster with improved oiling. Easy to do while your upgrading the valve springs.

Also the upgraded VCT solenoids. M-9297-M50A BTW list is $ 95 They are the set of 4, so cheap insurance especially if you are planning on multiple disassemblies . I believe that is when they are getting damaged. My OEMs one have never failed but I carried spares.

 

[honeybadger]

Thanks for all the responses guys. Appreciating the responses and conversations. This morning I realized I should weigh the pistons, pins, rods, bearings, etc. and see how much variation there is from the factory. Interesting results. Over 15 grams of variation.

My measured weights were:
#1 1166
#2 1168
#3 1177
#4 1181
#5 1180
#6 1178
#7 1179
#8 1178

 

[AceOne]

Thanks for all the responses guys. Appreciating the responses and conversations. This morning I realized I should weigh the pistons, pins, rods, bearings, etc. and see how much variation there is from the factory. Interesting results. Over 15 grams of variation.

My measured weights were:
#1 1166
#2 1168
#3 1177
#4 1181
#5 1180
#6 1178
#7 1179
#8 1178

Here's a better way to look at it.... only 1/2 ounce of difference! I have some comments on my first set of rods, but I need to run. post more later.

 

[Offboost]

Ponder on this info for a minute.

https://www.hemmings.com/magazine/hcc/2009/03/Balancing-Act/1779988.html
The law states that with the same amount of imbalance, the force will increase by the square of the RPM. For example, if the RPM doubles, the force quadruples, and if the RPM triples, the force of the imbalance increases ninefold.



For demonstration purposes, imagine a seemingly minute imbalance of one ounce in a crankshaft. Keep in mind that a crankshaft can weigh upward of 75 pounds, which would equal 1,200 ounces, so we are talking about an imbalance of 1/1200 of the total mass of the part. At 500 RPM, this would create a force of seven ounces. Raising the RPM to 5,000, the one-ounce imbalance would appear to the crankshaft as if it were 44 pounds heavier on one side--not very good for bearing life, because it would cause the crankshaft to deflect and wobble.


Also consider that the distance the imbalance is located from the axis of rotation has a multiplicative affect on the previous rule. For this reason, imbalance is referenced by the weight multiplied by the radius, recorded in inch/ounces. If that same one-ounce imbalance was moved farther out on the throw of the crankshaft, at 3,000 RPM it could equate to a force of 100 pounds pulling at the bearings. It is important to note that the amount of imbalance has not changed, but the force it now possesses has increased dramatically.


During the deflection created by the centrifugal force wanting to pull the crankshaft from its axis of rotation in the main caps, a vibration would be sent through the complete assembly. In engineering terms, a vibration is defined as a continuing periodic change in displacement with respect to a fixed reference: a motion that repeats itself in all particulars after a certain interval of time. This would now be translated into a harmonic motion, defined as the rhythmic vibration of a moving part or assembly.


Assuming an engine with 0.0025-inch bearing clearance, deflection of 0.001-inch would now reduce that clearance to 0.0015-inch. Since energy is being used by the imbalance to deflect the crankshaft, there is less available to push the piston down and create power. Although the amount of power loss created by a harmonic may be hard to quantify, decreases in engine longevity and RPM potential are very easily seen. This harmonic would also travel into engine-driven accessories, along with the transmission, reducing their life span.

 

[firestarter2]

Thanks for all the responses guys. Appreciating the responses and conversations. This morning I realized I should weigh the pistons, pins, rods, bearings, etc. and see how much variation there is from the factory. Interesting results. Over 15 grams of variation.

My measured weights were:
#1 1166
#2 1168
#3 1177
#4 1181
#5 1180
#6 1178
#7 1179
#8 1178

Is the crank ..... drilled? to offset the weight differences? I dont know t

Ponder on this info for a minute.

https://www.hemmings.com/magazine/hcc/2009/03/Balancing-Act/1779988.html
The law states that with the same amount of imbalance, the force will increase by the square of the RPM. For example, if the RPM doubles, the force quadruples, and if the RPM triples, the force of the imbalance increases ninefold.



For demonstration purposes, imagine a seemingly minute imbalance of one ounce in a crankshaft. Keep in mind that a crankshaft can weigh upward of 75 pounds, which would equal 1,200 ounces, so we are talking about an imbalance of 1/1200 of the total mass of the part. At 500 RPM, this would create a force of seven ounces. Raising the RPM to 5,000, the one-ounce imbalance would appear to the crankshaft as if it were 44 pounds heavier on one side--not very good for bearing life, because it would cause the crankshaft to deflect and wobble.


Also consider that the distance the imbalance is located from the axis of rotation has a multiplicative affect on the previous rule. For this reason, imbalance is referenced by the weight multiplied by the radius, recorded in inch/ounces. If that same one-ounce imbalance was moved farther out on the throw of the crankshaft, at 3,000 RPM it could equate to a force of 100 pounds pulling at the bearings. It is important to note that the amount of imbalance has not changed, but the force it now possesses has increased dramatically.


During the deflection created by the centrifugal force wanting to pull the crankshaft from its axis of rotation in the main caps, a vibration would be sent through the complete assembly. In engineering terms, a vibration is defined as a continuing periodic change in displacement with respect to a fixed reference: a motion that repeats itself in all particulars after a certain interval of time. This would now be translated into a harmonic motion, defined as the rhythmic vibration of a moving part or assembly.


Assuming an engine with 0.0025-inch bearing clearance, deflection of 0.001-inch would now reduce that clearance to 0.0015-inch. Since energy is being used by the imbalance to deflect the crankshaft, there is less available to push the piston down and create power. Although the amount of power loss created by a harmonic may be hard to quantify, decreases in engine longevity and RPM potential are very easily seen. This harmonic would also travel into engine-driven accessories, along with the transmission, reducing their life span.

Couldnt be offset by another piston in the opposing stroke? Kinda how an inline six counter balances it self?

You mention 44 lbs but using your math the piston it self weights 3500lbs. So assuming you math is right does 44 really matter? I assume adding in the force from the ignition the weights are even higher? In fact every time a cyclinder fired you have a far greater imbalance I would expect.

I am a bit of a layman just using the numbers you said.

 

[honeybadger]

Would you mind asking them if they recommend keeping the oil squirters? Aftermarket pistons seem to have larger clearances and wider ring gaps so I wonder how they play with the oil jets.

They do. The custom pistons they use from Diamond Pistons clear the squirters and he says they're absolutely necessary for road course use.

 

[Offboost]

Is the crank ..... drilled? to offset the weight differences? I dont know t


Couldnt be offset by another piston in the opposing stroke? Kinda how an inline six counter balances it self?

You mention 44 lbs but using your math the piston it self weights 3500lbs. So assuming you math is right does 44 really matter? I assume adding in the force from the ignition the weights are even higher? In fact every time a cyclinder fired you have a far greater imbalance I would expect.

I am a bit of a layman just using the numbers you said.

The Numbers are from the article I referenced.

Since the engine is a v and not opposed they do not cancel each other out but obviously companion cylinders should weigh as close to each other but all should be equal.

Is the crank ..... drilled? to offset the weight differences? I dont know t


Couldnt be offset by another piston in the opposing stroke? Kinda how an inline six counter balances it self?

You mention 44 lbs but using your math the piston it self weights 3500lbs. So assuming you math is right does 44 really matter? I assume adding in the force from the ignition the weights are even higher? In fact every time a cyclinder fired you have a far greater imbalance I would expect.

I am a bit of a layman just using the numbers you said.

Not my numbers I referenced the article, but you are correct in companion cylinders will help balance each other out but this is not a opposed motor or inline 4 its a 90 degree V so the forces are much different. The purpose of the post was to show that even a small amount of imbalance creates a lot of unwanted issues in a engine that spins to 8250 RPMs. I think ford did a decent job of trying to keep things balanced but a upgraded proper balance would certainly pay dividends in bearing life and operational smoothness.

If it was my engine I would certainly get a really good balance done to it while it is apart, if I was building this engine and wanted to change things I would put lighter titanium rods in it with a set of pistons that are at least the same weight as factory or hopefully lighter and stronger. I would then try to lighten the crank as much as possible safely. With upgraded springs and head it would probably be safe up to 9k but since the engine wont make power that high it would most certainly rev quickly to 8250 or even 8500 RPMs very quickly.

It would have been very cool if Ford would have given the 350 R owners titanium rods along with the carbon fiber wheels would have been a even better package.

 

[Strokerswild]

I understand the crank, by why the heads? If they are stored on a flat surface, then that's the same as being installed on the engine, no? And what is going to be deformed by horizontal storage?

Just curious, not challenging. I don't know the answer.

If a head is stored deck surface flat on a completely rigid, perfectly flat surface like an engine block, no worries. But if they need to sit around for any period of time they should be stood on end. No chance of potential warpage over time due to a non-flat storage surface, not to mention the possibility of damaging the deck/gasket surface. Something I was taught decades ago, and have always done.

Now, on to more GT350 internals porn....

 

[AceOne]

I put a Voodoo engine together in early 2016, the pistons were only $38. each lol. Check the part number for the tensioners. JL3Z-6L266-B is for the 5.0 Coyote. The current Voodoo # is GR3Z-6L266-A. I would expect them to just change the letter for a revision.

I just got clarification back form the engineer. The JL3Z-6L266-B is aluminum body and for the new 18+ motors. The GR3Z-6L266-A is the voodoo tensioner and is still available and is steel bodied so the preferred one to use for racing applications.

I do want to note the M-6004-A5015 kits came with the aluminum bodied tensioners and is what is in my current 600+ hp 8400rpm engine and has not been an issue. I will however be switching them to the GR3Z tensioners and also using the GR3Z ones in my new build. They are roughly $55 each.

Make sure the computer doesn't bump the GR3Z tensioners to the JL3Z version if ordering them as it did us.

 

[bauern]

They do. The custom pistons they use from Diamond Pistons clear the squirters and he says they're absolutely necessary for road course use.

I just got clarification back form the engineer. The JL3Z-6L266-B is aluminum body and for the new 18+ motors. The GR3Z-6L266-A is the voodoo tensioner and is still available and is steel bodied so the preferred one to use for racing applications.

Thank you both for the updates.

 

[AceOne]

They do. The custom pistons they use from Diamond Pistons clear the squirters and he says they're absolutely necessary for road course use.

I don't know why anyone would want to not use the oil squirters. The only drawback I know of is more windage but with the newest design in the 5.2 block with them in the main webs and the 50 psi pressure cut out I think they are very beneficial. 8K rpm get those pistons HOT! I'm eager to see how my motor looks on the teardown but i want to get this one done first so it will only be down a week.

 

[JAJ]

Thanks for all the responses guys. Appreciating the responses and conversations. This morning I realized I should weigh the pistons, pins, rods, bearings, etc. and see how much variation there is from the factory. Interesting results. Over 15 grams of variation.

My measured weights were:
#1 1166
#2 1168
#3 1177
#4 1181
#5 1180
#6 1178
#7 1179
#8 1178

OK, so let's think about these numbers. First, the Voodoo has a flat crank configured UDUD. So, if we look at each journal, we have the following pairings:

First UD journal pair:

UP #1 - #5: 1166 and 1180 for a total of 2346 going up
DN #2 - #6: 1168 and 1178 for a total of 2346 going down

Then the second pair:

UP #3 - #5: 1177 and 1179 for a total of 2356 going up
DN #4 - #8: 1181 and 1178 for a total of 2359 going down

It sounds pretty balanced to me - am I missing something? There's a 10g imbalance pair to pair and one pair is perfect while the second one is 3g off.

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