Stroke with only Pistons and Crank?

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340inabbody

340inabbody

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What are your thoughts about stroking my 340 with pistons and crank only and using my original factory rods? Will that work? Will that save me money? I would think the factory rods assuming that I have factory rods are as good as most current stuff out there??

Thanks and Merry Christmas guys!
 
No need to swap rods for a stroker build. But probably a good idea to recondition the stockers, which can cost as much as new and better rods, depending on your shop.

Have both quoted.
 
Stock rods are plenty strong. Especially when resized and good rod bolts installed.
 
If the rod length is stock then the pistons must be longer to get the full stroke correct? If this is the case how do I calculate/determine the stroker piston length? Who makes these types of pistons? I have yet to determine the actual stoke as this is the preliminary fact finding stages.
 
340inabbody said:
If the rod length is stock then the pistons must be longer to get the full stroke correct? If this is the case how do I calculate/determine the stroker piston length? I have yet to determine the actual stoke as this is the preliminary fact finding stages.
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Stroker pistons have a lower compression height. The piston is actually shorter, the pin closer to the deck.

Lots of stroker pistons available. Biggest choice is dished or flat, lower compression (dished) or high (flat). The choice will depend on how much cam you want to run and what you intend to do with the car.
 
Phreakish said:
Stroker pistons have a lower compression height. The piston is actually shorter, the pin closer to the deck.

Lots of stroker pistons available. Biggest choice is dished or flat, lower compression (dished) or high (flat). The choice will depend on how much cam you want to run and what you intend to do with the car.
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Thanks that makes sense more travel in a shorter piston. Good to know there will be a decent selection of pistons!
 
Any idea how much a shop would charge to recondition big end and bush a set of 8 would cost? Do they sonic test or magnaflux rods?
 
340inabbody said:
If the rod length is stock then the pistons must be longer to get the full stroke correct? If this is the case how do I calculate/determine the stroker piston length? Who makes these types of pistons? I have yet to determine the actual stoke as this is the preliminary fact finding stages.
Click to expand...
Choose a piston for the stock rod length and whatever stroke crank you want. Simple, really.
 
340inabbody said:
Any idea how much a shop would charge to recondition big end and bush a set of 8 would cost? Do they sonic test or magnaflux rods?
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Depends on location. I can get it done here for around 200-225. That's with me supplying the rod bolts.
 
A lot of people will refute reconditioning stock rods, saying new rods cost about the same or just a little more, which is true in some cases. I prefer using the factory Chrysler rods. All of the rods in that price range are from overseas and the original Chrysler rods have much better and consistent metallurgy, IMO.
 
The stroker kit is just about a no-brainer these days...
First you're going to have the block bored 30 over likely.. new cam bearings basically a block prep which is in the 5 to $700 area...
You'll have to buy a stroker crank, new main bearings, new pistons, new rings, and now the best you can do is maybe save $100 by reusing your old rods...
Now let's talk balancing all this or having it balanced with stock rods... $100 is now went way out the window...
Look on Summit internally balanced scat rotating assemblies are anywhere from 1400 to 1550... The 14 gets you cast Pistons and now you're going to have to decide if you want to pay the extra $150 for forged pistons for 1550 or so...
 
RustyRatRod said:
A lot of people will refute reconditioning stock rods, saying new rods cost about the same or just a little more, which is true in some cases. I prefer using the factory Chrysler rods. All of the rods in that price range are from overseas and the original Chrysler rods have much better and consistent metallurgy, IMO.
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Scat rods are made of forged steel here in the United states.
 
j par said:
Scat rods are made of forged steel here in the United states.
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No, they are not "made" in the United States. they are machined in the United States. They are forged or "made" overseas, like everything else.
 
RustyRatRod said:
Run what you want. I invite you to read my signature.
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I invite you to tell us how many strokers you've built with stock rods and what it cost to have the rotating assembly balanced you did... ZERO...
PXL_20210903_193852337.jpg

Scat rods are far superior and lighter than Factory 50-year-old stuff..
You'd probably be $350 into Mallory just trying to counterbalance those heavy Factory rods that aren't as strong or as precision made...
I've learned a lot from you but sometimes in life you have to realize you don't know it all...
 
j par said:
The stroker kit is just about a no-brainer these days...
First you're going to have the block bored 30 over likely.. new cam bearings basically a block prep which is in the 5 to $700 area...
You'll have to buy a stroker crank, new main bearings, new pistons, new rings, and now the best you can do is maybe save $100 by reusing your old rods...
Now let's talk balancing all this or having it balanced with stock rods... $100 is now went way out the window...
Look on Summit internally balanced scat rotating assemblies are anywhere from 1400 to 1550... The 14 gets you cast Pistons and now you're going to have to decide if you want to pay the extra $150 for forged pistons for 1550 or so...
Click to expand...

That's what it should be, but shops vary wildly and so do regions.

Best to get quotes for both routes and choose accordingly.
 
j par said:
I invite you to tell us how many strokers you've built with stock rods and what it cost to have the rotating assembly balanced you did... ZERO...
View attachment 1715841483
Scat rods are far superior and lighter than Factory 50-year-old stuff..
You'd probably be $350 into Mallory just trying to counterbalance those heavy Factory rods that aren't as strong or as precision made...
I've learned a lot from you but sometimes in life you have to realize you don't know it all...
Click to expand...
No, I've done a few. I was probably the first around here to do a 416 from a .070 over 360 back in the early 90s. Made mention of it many times. At that time, it was only about 175 to balance it, as Mallory metal was pretty reasonable. nothing crazy like it is now.
 
Phreakish said:
That's what it should be, but shops vary wildly and so do regions.

Best to get quotes for both routes and choose accordingly.
Click to expand...
Just from experience I went up and down this route a couple times and weighed all the differences.. at least with my local machine shop cost buying the kit again was a no-brainer..
 
j par said:
I invite you to tell us how many strokers you've built with stock rods and what it cost to have the rotating assembly balanced you did... ZERO...
View attachment 1715841483
Scat rods are far superior and lighter than Factory 50-year-old stuff..
You'd probably be $350 into Mallory just trying to counterbalance those heavy Factory rods that aren't as strong or as precision made...
I've learned a lot from you but sometimes in life you have to realize you don't know it all...
Click to expand...
Never said I know it all. Simply relaying my experience. Again, read my signature, please. Tons of people have used stock rods successfully through many DECADES at over 7500 RPM a lot. They will just hold up if prepared right. Sometimes, it's just personal preference. I'm not sure I'd ever use a new connecting rod, as "for me" I can approach reconditioning stock rods more affordable, since I can do it in stages, rather than bite off the whole purchase price at once.
 
RustyRatRod said:
No, I've done a few. I was probably the first around here to do a 416 from a .070 over 360 back in the early 90s. Made mention of it many times. At that time, it was only about 175 to balance it, as Mallory metal was pretty reasonable. nothing crazy like it is now.
Click to expand...
About 8 years ago I did my first Stroker and was not smart enough to buy the pre-balanced and it cost $275 and Mallory 8 years ago...
 
j par said:
About 8 years ago I did my first Stroker and was not smart enough to buy the pre-balanced and it cost $275 and Mallory 8 years ago...
Click to expand...
....and there's the "prebalanced" thing too. I guess I'm paranoid. I want someone locally that I know and trust to balance my stuff. Not a big assembly line outfit. ...again, just personal preference. It more fits my budget, in that I don't have to have a big cash outlay up front, but can chip away at it as I can afford to.
 
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