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Probably the 1000th one, but I need some help guys

Posted: June 15th, 2013, 7:58 am
by brandonwillyumz
Basics are that I have a 1996 Cherokee that IS a stick shift, and I want to stroke the engine out a bit. I've looked at the various comprehensive lists of parts needed for the different builds, and I think the one I want to go for is the "Low Buck Simple Stroker."
That list is this:
4.5L Low-buck simple stroker

Jeep 4.2L 3.895" stroke crank
Jeep 4.2L 5.875" rods
Jeep 4.0L 3.875" standard bore pistons
9.7:1 CR
CompCams #68-231-4 206/214 degree camshaft
Ported HO 1.91"/1.50" cylinder head
Stock 0.051" head gasket
0.081" quench height
Ford 24lb/hr injectors with adjustable FPR or MAP adjuster for '87-'95 engines, Ford 24lb/hr injectors with stock 49psi FPR for '96 and later engines
266hp @ 4950rpm, 322lbft @ 3500rpm


I know that those parts are not the entire list of things needed for the build, at least I think not. What I'm asking of you guys is to kind of send me in the right direction as far as where to acquire the parts I'll need for this. The engine is still in my Jeep currently, but I'll be removing it shortly and disassembling it.

I also need to know what to get done at a machine shop to utilize what I want to get here. Should I have it machined first, and then figure out the necessary parts? I've done a lot of work to my Jeep and other cars, but am very new to engine building and rebuilding, so please bear with me here. Thanks, in advance. :cheers:

Re: Probably the 1000th one, but I need some help guys

Posted: June 15th, 2013, 12:08 pm
by Cheromaniac
Unless yur engine is very low mileage I suggest that you have the cylinders in the block measured by the machine shop for ovality and taper. You may need to have them overbored depending on their condition.
You can find most of the aftermarket parts you'll need for the stroker build (apart from crank & rods) from Summit Racing. Here's a link that'll help you with your parts search:

http://www.jeepstrokers.com/forum/viewt ... =34&t=3036

Re: Probably the 1000th one, but I need some help guys

Posted: June 16th, 2013, 6:34 am
by brandonwillyumz
Thanks, I was planning on taking the block and head to a machine shop to have it all freshened up. Wouldn't I need to get it bored out if I wanted to stroke it?

Re: Probably the 1000th one, but I need some help guys

Posted: June 16th, 2013, 7:44 am
by JPrubo
brandonwillyumz wrote:Thanks, I was planning on taking the block and head to a machine shop to have it all freshened up. Wouldn't I need to get it bored out if I wanted to stroke it?
Not necessarily, boring a block means enlarge the cylinder holes for larger pistons. This does increase displacement but not all that much (.060" = .1 liter roughly) it's mostly to take up the wear engine experiences with mileage. Once the cylinders are wore you take them out a little further and then put in new larger pistons to get your clearances back to stock.

Stroking an engine increases the displacement of and engine move changing cranks that have a longer throw or stroke. This cause the piston to move up and down further thereby displacing more air. This is what cause's your biggest displacement differences (.482" = .6 liters roughly).

If you have high mileage on your motor then you will want to have the clearances checked, piston to cylinder wall, out of round, scratches in the walls, check the deck for flatness, check your valves to make sure they are sealed, the valve guides for clearance, check the head for flatness, and of course you will need a rebuild kit with new gaskets and seals all around. Make sure you check all wear items like time chains (might need a new one based on cam as well), oil pump, water pump. Remember you don't want to stroke and then have it blow up cause you reused something that was wore.

Re: Probably the 1000th one, but I need some help guys

Posted: June 16th, 2013, 12:24 pm
by brandonwillyumz
Thanks, that was basically exactly what I was looking for.