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Hahaha! Are you kidding? Common now, this is a joke, right?

A 4.6 Stroker is a 258 crank, and a bore job of I think 30 or 40 over.
 

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Recovering XJ owner
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They are not all the same ... technically. There's a heavy weight and light weight which you can tell by the number of journals on the crank. Typically to keep it simple: a heavy weight (earlier year and manual models) seems to be more desireable for a smoother idle.

Difference in power between the two cranks ... no.


edit: Same thing I ask everyone else ... Why not 4.7L?
 

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Recovering XJ owner
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ok, whats the diff, apparently bore or stroke.
both.

Please go to "Jeep Tech" in the forums and search: Stroker. You're going to find lots of info and links to very helpful info.
 

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Premium Member
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NO NO NO NO! There are differences in CRANKS, but the bearing JOURNALS are all the same :sonicjay:

The earlier cranks are VERY counter wieghted, there is a counter wieght on the other side of every rod journal. Those are considered heavy cranks, and because of the extra spinning wieght it may help balance and give better torque, but you will notice a lag of rpm jump when gettign on it ( i noticed it at least).

Other wise the stroke of all the 258 crans should be the same.

FYI, the key to a "good" stroker is all in the piston design, period.
 

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Mr. Special Snowflake.
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NO NO NO NO! There are differences in CRANKS, but the bearing JOURNALS are all the same :sonicjay:

The earlier cranks are VERY counter wieghted, there is a counter wieght on the other side of every rod journal. Those are considered heavy cranks, and because of the extra spinning wieght it may help balance and give better torque, but you will notice a lag of rpm jump when gettign on it ( i noticed it at least).

Other wise the stroke of all the 258 crans should be the same.

FYI, the key to a "good" stroker is all in the piston design, period.
Before making statements like you do. Learn something about the subject.

All in the piston design ? You are joking or have no idea what you are talking about.

Ever hear anything about bore to stroke ratio ? How about Dwell time ? Perhaps rod length to stroke ring a bell ?
 

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Bike Dude
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Before making statements like you do. Learn something about the subject.

All in the piston design ? You are joking or have no idea what you are talking about.

Ever hear anything about bore to stroke ratio ? How about Dwell time ? Perhaps rod length to stroke ring a bell ?
He has one of the baddest sounding strokers by the way... strange loping rumble of a V8 mixed with the wine of an inline.

It was music to my ears the first time i heard it:woot:
 

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Before making statements like you do. Learn something about the subject.

All in the piston design ? You are joking or have no idea what you are talking about.

Ever hear anything about bore to stroke ratio ? How about Dwell time ? Perhaps rod length to stroke ring a bell ?

listen closely to what he tells you...he KNOWS what he's talking about.
 

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He has one of the baddest sounding strokers by the way... strange loping rumble of a V8 mixed with the wine of an inline.

It was music to my ears the first time i heard it:woot:
Thanks for the kind words.

Sorry if I spoke a bit gruf. My time of the month.

Be happy to discuss stroker builds anytime. There is a whole lot more to it then throwing a bunch of parts together. Simply overboring a 4.2 is not making a stroker.

In the simplest sense a stroker combines a 4.2 crank with a 4.0 block.
For the most part the block isnt that important. Nor is the crank. But are things that you need to know to do it properly. Rods/pistons/quench/cam timing etc.

A good source for information is the Yahoo strokers group.

http://autos.groups.yahoo.com/group/strokers/
 

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listen closely to what he tells you...he KNOWS what he's talking about.
Hey Dave, how is your project going ? Give me a call and let me know how the project is coming.
Did you see that thread over on Pirate on the forced injection Corey is doing ?
 

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Recovering XJ owner
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He has one of the baddest sounding strokers by the way... strange loping rumble of a V8 mixed with the wine of an inline.

It was music to my ears the first time i heard it:woot:
Mine is hopefully one of the other ones ... I hadn't realized how obnoxious it sounded until I eliminated the hatch. Once this 40 series get smashed, I'm going to switch to a 50.



I'm still trying to figure out what piston design to use in the next stroker?:tonka:
 

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so like a 73-79 crank would be "heavy"?
Yes, those are the "heavy" ones, up to (I think) '81. '87 and up are the correct length, so you don't need to shorten them or get a spacer. You should really spend a lot of time reading up at the yahoo groups list posted before. There are several sites with good info, this one's pretty handy:

Dino

And right here on GL4x4: Muddypaws

The photos seem to be dead, but there's good info.
 

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Mr. Special Snowflake.
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Before making statements like you do. Learn something about the subject.

All in the piston design ? You are joking or have no idea what you are talking about.

Ever hear anything about bore to stroke ratio ? How about Dwell time ? Perhaps rod length to stroke ring a bell ?
Bore to stroke ratio? The stroke is pretty much given beyond the small gains that can be had with offset grinding the crank. Bore will be driven by how much you can over bore the block and whether you want to go with an off the shelf piston diameter or something custom.

Dwell time and rod length to stoke ratio are pretty much 2 sides ofthe same coin. They go hand in hand. And as previously mentioned you do not have a huge choice of strokes. For rod length you pretty much have 2 choices, stock 4.2 (5.875") or stock 4.0(6.125") with few, expensive, other options. If you run the 4.2 rods you can run stock pistons but if you want to alter the dwell time or rod ratio you would need to run custom pistons.

Other things you didn't mention are compression ratio, which given a stock cumbustion chamber in the head may require a dished piston to get right, cam timing and valve sizing, which may require notches in the piston to get to work, quench, which may require altering the compression height of the piston to get right...

So yeah, there are lots of other things to consider, but most of them come right back to piston design. Considering all the main parts, block, crank, rods, pistons, and heads, the pistons are the only ones you have real control of the design of without costing huge amounts of money.
 
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