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Best stroker combo?

CW

NAXJA Forum User
Hey, I am getting ready to do my stroker build and am compiling my list of parts. What rods would you suggest using the 242 or the 258? What pistons are you using and how happy are you with them?
So far my idea is to use an older 258 crank for more torque over the newer, .30 overbore, HO head, 2000+ intake manifold, viper tb, 3" exhaust, air tube, and a crane cam.
I think this will give me a pretty decent engine if I could figure out what crank and rod combo I need to make it run.
-TIA
 
I would sugest using the 258 connecting rods, if not your pistion may contact the valves.
 
Out of curiosity, how do you figure that using the 258 rods will give you more torque than the 4.0L rods? The stroke will be the same in both situations.

Have you discovered the Strokers group on Yahoo yet? If not, find the URL (I apologize, but I don't have it bookmarked) and spend some time there. I will give you a link to a web page of one of the gurus from the Strokers group, and he spells out a few different approaches.

Basic point: because of minor differences in deck height, rod length, and piston pin height, if you run 258 rods with stock replacement 4.0L pistons the compression ratio gets too high for 87 octane gasoline. The only way around this is to use a piston with enough crown thickness to allow milling a deeper dish.

The alternate route is to use the 4.0L rods, but then the stock pistons sit too far down in the hole. Accurate Power offers custom forged pistons with a modified pin height to compensate for this. Some folks claim forged pistons are too noisy until the engine warms up -- others don't seem to have a problem. Using the 4.0L rods with the custom pistons gets you an engine that will run on 87 octane, PLUS the 4.0L rods are significantly beefier and stronger than the 258 rods.

Here's the URL for the stroker "recipes":

http://www.jeep4.0performance.4mg.com/photo3.html
 
When I said I want to use the older 258 crank I was refering to the two versions of the 258 crank the newer lighter one and the older heavier one. At least thats what I picked up around the web.
 
The heavy crank does not make any more torque than the light crank. What it does is add more rotating mass, accomplishing the same thing as running a heavier flywheel. Same torque, but better resistance to stalling if you run a manual transmission because of the added intertia.

On the other hand, if you run an automatic you might prefer the lighter crank because with less intertia it will spin up a tad faster, as well as give you slightly better engine breaking.
 
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