Jeep Strokers

Hey all!
New to the site, been lurking, researching and reading for over 6 months though. I'm in the process of finishing up a 4.6L stroker build. I figured i would start a thread, share some pics with everyone. I started this build last fall, a friend of mine did all of the machining and assembly work. I just supplied him with the goodies. The block is out of a 94' grand cherokee and will be going into a different 94' grand cherokee. Some specs.

94' 4.0 block
port and polished 7120 head
reground .010 undersize 258 crank
4.0 connecting rods
arp main and rod bolts
keith black ic944 .030 over pistons
comp cams 68-231-4 camshaft
mopar performance valve springs
mopar high volume oil pump
flowkooler high flow water pump
mopar .043 head gasket
all new cam, main and rod bearings
new harmonic balancer
high flow thermostat
high flow thermostat housing

random parts


bottom end all assembled! decked the block appx. .020, new freeze plugs and a fresh coat of paint.


All assembled! and freshly painted.


This is the jeep that it will be going in. Aside from the motor the rest of the jeep is stock. I race it at a few local tracks, where they call it "beater cross". Reason for building the stroker is I keep losing to a friend with a v8 5.2 grand cherokee


Pic taken 2 years ago of another jeep i own. this ones completely stock

I just pulled my jeep into the garage and am getting ready to do the swap. I've done about a half dozen 4.0 swaps already so this one shouldn't be to bad. I'm planning on putting an AW4 behind the stroker and ditching the 42re. I just need to figure out the wiring for that.

I still need a few more parts too, looking for a 62mm throttle body, 24lb injectors, If someone can recommend a set from summit or jegs that would be sweet!. I hope to have this thing running In 2 or 3 weeks, then bring it in and have it dyno'ed.

Thanks for posting. I will be using nearly the same recipe. Except for the high flow pumps, and mine is a wj...My machinist told me that a high flow oil pump can keep too much oil in the top end leaving your sump to lose suction. True or not?? What does your C/R work out to be? Did you do your own porting? I am doing some right now and would love to see pics of your head if you have any. Keep us posted.

akadeutsch wrote:.My machinist told me that a high flow oil pump can keep too much oil in the top end leaving your sump to lose suction. True or not??

Myth. The flow is limited by the clearances in the engine. In short, if the clearances were so large to allow all the oil to be pumped into the valve cover you would have very little oil pressure (if any) with either pump. This was also proven false by Smokey Yunick using high speed photography and windows on the oil pan and valve covers.

Got the old engine pulled today, and cleaned the engine bay up for the new one.



before the clean up


and after

akadeutsch wrote:Thanks for posting. I will be using nearly the same recipe. Except for the high flow pumps, and mine is a wj...My machinist told me that a high flow oil pump can keep too much oil in the top end leaving your sump to lose suction. True or not?? What does your C/R work out to be? Did you do your own porting? I am doing some right now and would love to see pics of your head if you have any. Keep us posted.

I dont know the exact c/r off the top of my head but it is somewhere around 9.5:1 I had my friend port the head and do a 3 angle valve grind. I'll see if I can get some pics from him.

orty65 wrote: Reason for building the stroker is I keep losing to a friend with a v8 5.2 grand cherokee

The stroker is going to walk all over the 5.2L. If not its driver error.

Beater-cross looks like a ball! Nice looking motor! Keep us posted on the dyno results....

Well the motor is in its new home, I got the transmission hooked up, all the accessories bolted up, pretty much everything excpet the injectors and throttle body.

Filled the motor up with oil, then primed the system using an old distributor and a drill. After about 20 seconds of pumping oil started pouring out the rear of motor. Rear of the valve cover looked good, So i'm thinking either rear main seal or the oil pan gasket? It almost looked like it was leaking higher up than the oil pan. Not sure what the next step is yet.

orty65 wrote: It almost looked like it was leaking higher up than the oil pan. Not sure what the next step is yet.

Rear oil galley plug maybe?

I6FAN wrote:

orty65 wrote: It almost looked like it was leaking higher up than the oil pan. Not sure what the next step is yet.

Rear oil galley plug maybe?

The galley plug above the camshaft freeze plug was in. The did seem to be more oil coming from the passaganger side though

[quote="orty65
The galley plug above the camshaft freeze plug was in. The did seem to be more oil coming from the passaganger side though[/quote]

Or a leak in the camshaft plug was another thought as well?

Aren't those two freeze plugs at the rear of the engine for coolant passages?

Just dropped the oil pan, the gasket looked ok.

Update! I solved the oil leak issue, ended up pulling the transmission and sure enough the rear galley plug was nowhere to be found Put the plug back in and it no longer leaked oil! Got the tranny mounted back up, all of the accesories on, added coolant, shortly after that coolant started dripping on the floor. Coolant was leaking from the freeze plug at the rear of the head, luckily I don't have a dash and was able to cut a hole in the firewall to easily get at it lol.

So today I was able to start it up for the first time, it runs kind of rough, shaked at startup, didn't want to idle very well and would backfire every now and then. Seemed to be running really rich? Once it got higher into rpms 2500-3000 it seemed to clear out and sounded nice. I did get some 24# injectors for it, still have the stock throttle body which probably isnt helping. Any ideas what would cause it to run so rough? Timing off one tooth? cam not degree'd properly? Vacum leak?

Another update: Solved the hard start, rough running issue. The rotor was pretty rusty, so i ended up buying a new distributor , re timed the eninge and it fired right up and purred nicely!! Immediately brought it up to 2000 rpm then varied it between 2-500 rpm for 25 minutes, coolant temp went up to 210 and stayed there. Oil pressure was around 15-20 psi. Not sure what normal should be?

I still have to figure out the wiring for my aw4 transmission to get it driveable. Hoping to get that taken care of this week, so I can get it on the dyno in the next week or two.

Also wondering if I should change the oil now, or just the filter? Did a search and got mixed results. I'm runninng royal purple break-in oil in it now.

if you really want to give it some air get a dodge or jeep 4.7 throttlebody and run this adapter. i designed it last year and a buddy makes them

http://www.ebay.com/itm/like/191118014177?lpid=82