Modular 5.0 stroker kits, any high mileage builds out there?

[cobraman1024]

My concerns about the piston side loading caused by using the custom pistons and required shorter 5.85" connecting rod needed for the 3.8" Kellogg crankshaft have not been alleviated. In fact, I'm about 99% convinced that I should just stick with a stock stroke 4.6L build.

Does anyone out there have a high mileage modular 5.0 stroker build? I'm looking for engines that still run well without any unexplained increase in oil usage between changes.....generally 50,000+ miles. I was told that the pistons used for this build would basically need to be replaced before reaching 50,000 miles which is why I threw out that number.

 

[gt347mustang]

From the looks of your sig, you drive the dirt out of your vehicles!

I'm interested to see who's putting a lot of miles on their stroker kits.

 

[cobraman1024]

From the looks of your sig, you drive the dirt out of your vehicles!

I'm interested to see who's putting a lot of miles on their stroker kits.

Yeah, you could say that LOL
This is exactly why I want to build something that will last another life of the vehicle. Between my wife and I , we do probably 12,500 miles/year on any given car in my sig.

 

[Shaunk]

What do you plan to do with the car? hp level? forced induction?

 

[cobraman1024]

N/A for now and as long as it breaks in fine and holds up well for the first few years, then Forced Induction........Haven't decided if it will be a turbo yet (although I do have the Hellion clearanced MM k-member) or Procharger.

 

[shurur]

I wonder if a 5.3L BB (3.7")/ stroker (3.75") would make a difference on wear and side-loading, etc.

BTW you have a few of the same threads out there!!

And I had wondered why MMR made a 3.6 stroker (from the coyote crank)and was told it was price points/marketing....and Ford a 3.5X3.5 4.6L............3.6X3.6 5l coyote.........3.7X3.7 5.3L BB Stroker...????
Maybe there is a reason for the Ford square engine...wear-wise/geometry-wise..?
There may be some tipping point beyond a square engine and this AL block.

But then again Ford is making a 5L shortblock now..
https://www.fordracingparts.com/parts/part_details.asp?PartKeyField=22907

And they are using the 3V block..availability?? or something more???

Time will tell.

 

[cobraman1024]

I wonder if a 5.3L BB (3.7")/ stroker (3.75") would make a difference on wear and side-loading, etc.

BTW you have a few of the same threads out there!!

And I had wondered why MMR made a 3.6 stroker (from the coyote crank)and was told it was price points/marketing....and Ford a 3.5X3.5 4.6L............3.6X3.6 5l coyote.........3.7X3.7 5.3L BB Stroker...????
Maybe there is a reason for the Ford square engine...wear-wise/geometry-wise..?
There may be some tipping point beyond a square engine and this AL block.

But then again Ford is making a 5L shortblock now..
https://www.fordracingparts.com/parts/part_details.asp?PartKeyField=22907

And they are using the 3V block..availability?? or something more???

Time will tell.

I posted the same thread on multiple forums and in multiple sections to get the widest possible viewing. The shortblock itself can be used for a 2v, 3v or 4v engine so basically a GT, Bullitt, Mach 1 or Cobra.
Again, the Ford Racing stroker is using a 3.75 crank so yeah there probably is something having to do with the square geometry of it.
MMR wants to insist on the 3.8 stroker crank not having any issues yet none of the other major engine builders are selling/using it.......Kinda tells me there might be a durability issue which is why I started this thread. I wanted to see if anyone had a durable shortblock with the 3.8 crank.

 

[shurur]

I posted the same thread on multiple forums and in multiple sections to get the widest possible viewing. The shortblock itself can be used for a 2v, 3v or 4v engine so basically a GT, Bullitt, Mach 1 or Cobra.
Again, the Ford Racing stroker is using a 3.75 crank so yeah there probably is something having to do with the square geometry of it.
MMR wants to insist on the 3.8 stroker crank not having any issues yet none of the other major engine builders are selling/using it.......Kinda tells me there might be a durability issue which is why I started this thread. I wanted to see if anyone had a durable shortblock with the 3.8 crank.

It was my understanding that the 3.8 crank was a proprietary saleen crank, and everyone else, including MMR, was using the 3.75 crank..sometimes calling it a 3.7 crank...maybe even calling it a 3.8 crank..but not to me confused with the Saleen 3.8 crank...

And I thought the saleen 3.8 crank needed some head work on the 2v to make it work..???

 

[SlowSVT]

A few years ago Kellogg had advertised a 3.4XX" short stroke mod motor crank on their web site. I was interested in using this crank in my Boss block which would have reduced the displacement down to 289 cu in. Talking with the tech at Kellogg he stated they never actually made one. Turning the blank was not the problem, it was the drill angle for the oiling holes and they were not interested making even a small batch of them for a GB.

As a long stroke creates problems a short stroke has the opposite effect. It pushes the piston further into the cylinder providing better stability for the piston, it gets you a longer rod for improved rod/stroke ratio, slows the piston down and less load on the rotating assembly. That engine would hold power and Revs better then even the stock stroke mill. Giving up the 16 cubes is the price to be paid for doing that but it was something I would have considered.

You can beat the crap out of a short stroke motor like you favorite hound dog and he will still love you for it

 

[cobraman1024]

A few years ago Kellogg had advertised a 3.4XX" short stroke mod motor crank on their web site. I was interested in using this crank in my Boss block which would have reduced the displacement down to 289 cu in. Taking with the tech at Kellogg he stated they never actually made one. Turning the blank was not the problem, it was the drill angle for the oiling holes and they were not interested making even a small batch of them for a GB.

As a long stroke creates problems a short stroke has the opposite effect. It pushes the piston further into the cylinder providing better stability for the piston, it gets you a longer rod for improved rod/stroke ratio, slows the piston down and less load on the rotating assembly. That engine would hold power and Revs better then even the stock stroke mill. Giving up the 16 cubes is the price to be paid for doing that but it was something I would have considered.

You can beat the crap out of a short stroke motor like you favorite hound dog and he will still love you for it

Interesting!

 

[IUP99snake]

I wonder if a 5.3L BB (3.7")/ stroker (3.75") would make a difference on wear and side-loading, etc.

BTW you have a few of the same threads out there!!

And I had wondered why MMR made a 3.6 stroker (from the coyote crank)and was told it was price points/marketing....and Ford a 3.5X3.5 4.6L............3.6X3.6 5l coyote.........3.7X3.7 5.3L BB Stroker...????
Maybe there is a reason for the Ford square engine...wear-wise/geometry-wise..?
There may be some tipping point beyond a square engine and this AL block.

But then again Ford is making a 5L shortblock now..
https://www.fordracingparts.com/parts/part_details.asp?PartKeyField=22907

And they are using the 3V block..availability?? or something more???

Time will tell.

I'm not sure that the larger bore will reduce the side loading of the pistons on a stroker application because the length of the bore (or sleeve) from the top to bottom remains the same. Even though the bore/stroke ratio improves, the "bore length"/stroke ratio does not.

As a result of the less favorable bore length/stroke ratio, the wrist pin is moved up higher into the ring lands. Additionally the piston skirt is shortened to avoid contacting the counterbalance on the crank during BDC.

On a taller deck motor with the same (or longer) stroke, these modifications to the geometry of the piston would not be required. (Like with a 5.4).

It is these modifications to the piston that cause longevity issues in modular stroker applications.

 

[SlowSVT]

I'm not sure that the larger bore will reduce the side loading of the pistons on a stroker application because the length of the bore (or sleeve) from the top to bottom remains the same. Even though the bore/stroke ratio improves, the "bore length"/stroke ratio does not.

As a result of the less favorable bore length/stroke ratio, the wrist pin is moved up higher into the ring lands. Additionally the piston skirt is shortened to avoid contacting the counterbalance on the crank during BDC.

On a taller deck motor with the same (or longer) stroke, these modifications to the geometry of the piston would not be required. (Like with a 5.4).

It is these modifications to the piston that cause longevity issues in modular stroker applications.

I think the term you are looking for is: "rod/stroke ratio". That has a direct bearing on the piston side loads. The bore is not related to this issue.

 

[shurur]

I'm not sure that the larger bore will reduce the side loading of the pistons on a stroker application because the length of the bore (or sleeve) from the top to bottom remains the same. Even though the bore/stroke ratio improves, the "bore length"/stroke ratio does not.

As a result of the less favorable bore length/stroke ratio, the wrist pin is moved up higher into the ring lands. Additionally the piston skirt is shortened to avoid contacting the counterbalance on the crank during BDC.

On a taller deck motor with the same (or longer) stroke, these modifications to the geometry of the piston would not be required. (Like with a 5.4).

It is these modifications to the piston that cause longevity issues in modular stroker applications.

ok makes sense..I'm not an engine builder and haven't got a firsthand look at any of these component.....yet.

Now I'm wondering aloud (again) if maybe the MMR 5.15L stroker 3.7X3.6 would be a better design..it sounds like it depends on the piston/wristpin needed for that stroke.

I had originally asked MMR if there was a problem with the 3.75 stroke design..and whether the 3.6 was the new ford crank...answer was no and yes respectively..

I'd like to keep my teksid and dry-sleeve it for 3.7 bore someday..
I'm staying NA and DD.
Thanks

 

[trxcobra]

18k on mine so far, no oil consumption problems yet

 

[IUP99snake]

I think the term you are looking for is: "rod/stroke ratio". That has a direct bearing on the piston side loads. The bore is not related to this issue.

The rod/stroke ratio is important when building a stroker for the reasons you described.

I'm not sure if the metric I described is an actual ratio used by engine builders, but I'm pretty sure it's important, not for calculating piston speeds but for determining how much stroke is feasable given the deck height and sleeve length... and the sacrifices in the piston design that must be made in order to keep it from extending past the top or bottom of the bore given the extra travel associated with an increased stroke.

For example, the 5.4 has a longer stroke than the 4.6 but the pistons are interchangeable despite the longer stroke in the 5.4 because the length of the liner in the 5.4 is also increased by an equal proportion to the increase in stroke.

But if one were to increase the stroke in a 4.6, changes need to be made in the piston design to keep it from protruding from the top or bottom of the cylinder liner. This includes shortening the skirt and moving the wrist pin higher up in the ring lands.

Feel free to call me out if I'm not making any sense whatsoever.

 

[SlowSVT]

The rod/stroke ratio is important when building a stroker for the reasons you described.

I'm not sure if the metric I described is an actual ratio used by engine builders, but I'm pretty sure it's important, not for calculating piston speeds but for determining how much stroke is feasable given the deck height and sleeve length... and the sacrifices in the piston design that must be made in order to keep it from extending past the top or bottom of the bore given the extra travel associated with an increased stroke.

For example, the 5.4 has a longer stroke than the 4.6 but the pistons are interchangeable despite the longer stroke in the 5.4 because the length of the liner in the 5.4 is also increased by an equal proportion to the increase in stroke.

But if one were to increase the stroke in a 4.6, changes need to be made in the piston design to keep it from protruding from the top or bottom of the cylinder liner. This includes shortening the skirt and moving the wrist pin higher up in the ring lands.

Feel free to call me out if I'm not making any sense whatsoever.

Maybe I can clarify.

It's the length of the rod in relationship to the stroke.

5.933 (rod length) / 3.522 (stroke) yields a 1.67:1 rod/stroke ratio on the 4.6.

A 3.75 stroker has a 1.58:1 rod/stroke ratio which is not as good as the 4.6

I think 1.75:1 is considered ideal but some F1 cars go as high as 2:1

 

[shurur]

bookmarking this thread...

 

[IUP99snake]

Maybe I can clarify.

It's the length of the rod in relationship to the stroke.

5.933 (rod length) / 3.522 (stroke) yields a 1.67:1 rod/stroke ratio on the 4.6.

A 3.75 stroker has a 1.58:1 rod/stroke ratio which is not as good as the 4.6

I think 1.75:1 is considered ideal but some F1 cars go as high as 2:1

I know the rod length is an important component of a well designed stroker setup and the rod ratio is a meaningful piece of data. But what I'm trying to describe concentrates on the stroke in proportion to the deck height or cylinder bore liner length.

Ultimately, the deck height or cylinder bore length is the limiting factor in how much stroke is possible because there's only so much room for the piston to travel up and down.

The LSx people have been building a 454-based 572 LSx stroker. Previously the 454 was the largest that could be done given the deck height and liner length constraints. In order to add enough additional stroke to make a 572, a "tall deck" LSx block was introduced. I've also seen standard deck LSx blocks modified with spacers above the original deck in order to press in longer cylinder liners to accommodate the extra stroke without making the piston design completely unreliable.
Despite the rod ratio, the LSx people were able to go with a much longer stroke by using a taller deck block with longer liners instead of making additional sacrifices to the piston skirt and wrist pin location.

The 5.4 has a taller deck height and a longer cylinder liner compared to the 4.6. Despite having a significantly longer stroke than even a 4.6 based stroker motor, the 5.4 is able to use the same pistons as a stock 4.6 because there's more room for the piston to travel up and down within the bore in the taller deck block. But when you increase the stroke in the 4.6, there needs to be a modified piston design to prevent it from protruding from the top or bottom of the cylinder liner.

Since I don't have the data the cylinder bore length for a 4.6 or 5.4, I'll use the deck height as a substitute to demonstrate how this is calculated.

5.4: 10.079" deck height / 4.17" stroke = 2.41
(The deck height is 2.41 times greater than the stroke)

4.6: 8.937" deck height / 3.55" stroke = 2.51
(The deck height is 2.51 times greater than the stroke)

5.0 Stroker: 8.937" deck height / 3.75" stroke = 2.382
(By increasing the stroke, the deck height is now only 2.382 times greater than the stroke compared to 2.41 times with the 5.4. Even though the 5.4 has a much longer stroke and a worse rod ratio than a 5.0 stroker, it has a more favorable deck height to stroke ratio which allows them to use the same pistons as a stock 4.6 without having to use a stroker specific piston like what would be seen in a 5.0 stroker.)

It all really starts with the deck height or cylinder liner length.That's what dictates how much additional stroke is feasable given the sacrifices made to the piston.

Like I said before, I'm not sure if this metric is used by engine builders or not. But based on my experience with engine building and the design of stroker packages, I think this type of ratio is important given how much additional stroke is feasable given the constraints associated with the deck height or cylinder liner length

 

[SlowSVT]

It all really starts with the deck height or cylinder liner length.That's what dictates how much additional stroke is feasable given the sacrifices made to the piston.

Like I said before, I'm not sure if this metric is used by engine builders or not. But based on my experience with engine building and the design of stroker packages, I think this type of ratio is important given how much additional stroke is feasable given the constraints associated with the deck height or cylinder liner length

True statement but we are kinda stuck with the low deck 4.6 block. If you wanted to spin your engine into the stratosphere and improve the geometry a 5.4 block with a 4.6 crank and longer rods to make-up for the added deck would be hard to beat but now you got a bigger lump nestled in the engine bay and 40 more lbs on the nose of the car. Not many, if any will go that route.

Like you said, this engine needs more cylinder length. That would make the pistons more tolerant of a stroker.