4.0 stroker, 258 ?

cardudenc

cardudenc

jeep a holic, resident assho;e
Joined
Sep 21, 2007
Location
morganton
I know this has been covered several times, but I got a fews ?'s about mine. I got a 4.0 off here that was supposed to only have around 18,000 miles.I had bought a mopar performance cam awhile back, so when I got it home I pulled the head and water had been in the cylinders. since I have to tear it down I figure might as well do a stroker. I think I can get by with just honing the cylinders. since I will be changing rods should I get aftermarket pistons? if so what is everyone running? I will post the specs on the cam later to see if it will be decent with the stroker.
I have a running 258 I pulled out of my truck. it is complete the way it was running in the truck. what r these bringing? trying to decide whether to pull it down for the crank and rods or sell it and buy new crank and rods.
thanks
 
what is the duration of the cam at .050", and is it a single profile cam, or dual? (meaning does it have the same specs for intake and exhaust or different?)

as for pistons, if you can get by w/ just honing, and that cleans up the cylinder walls, then you are fine to re-use the ones you have. If you do reuse your current pistons, I would reccommend putting them 180 degrees backwards on the 258 rods when you reassembly everything. Meaning, they are backwards as compared to stock orientation. The pistons in stock form has the arrow facing forward, you want the arrow to face backwards. This will give you some more torque, and all you will notice is a little more piston slap than before. ( ie: the way the newer chevy lsX... engines sound at idle, compared to an older small block)

Pm me if you have any questions.
 
How will that give you more torque?
 
less friction on the side of the piston that is in contact w/ the cylinder wall at tdc, and going from TDC to BDC, and mainly better rod to piston geometry. it also helps the stroker engine stay together longer during hard revs. The rod to stroke ratio when using a 258 rod and 258 crank, w/ 4.0 piston is not that great, and this also helps to keep from pulling the piston pin out of the bottom of the piston.

its not like its going to give you as much torque are porting the head, or cam swap, but a little here and a little there can always help right?
 
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