Jeep Strokers

I am building a stroker motor right now. 93 yj 4.0 block. Bored out 30 over.4.2 crank.4.2 rods. What I am looking for is my head springs are stock. So what cam do I use? Or can I use the stock one? And later next winter or when ever change head springs and cam out? Its going in a 93 yj 5speed. 8.8 locked. 33in tires 4.10 gears full body armor. And flat tube fenders. I am running a cold air intake. 2.25 exhaust with a flowmaster muffler. All said about this motor build would it be the 4.6 or 4.7. Thanks guys..

If you want to keep the engine simple and reliable, just use the stock cam with stock springs as I did. Your engine will displace 4587cc so it'll be a 4.6.

Ok found out my lifters and cam is not in the best shape. So in need of a cam and lifters. What cam will work with stock springed head? Thanks guys. I have looked but don't want to blow something apart.

There are a few cams on my spreadsheet at http://www.angelfire.com/my/fan/Jeep4.0Camshafts.htm with a valve lift of 0.45" or less and I suggest you go for the Crower 44243.

Cheromaniac wrote: I suggest you go for the Crower 44243.

That's the one I chose. With the stock springs it revs nicely to the 5000 rpm shift point.
It's a tad more cam than stock, which I felt was a nice match to the extra cubes of the 4.6.
I can't offer any before/after driving impressions, as I barely drove my Jeep before the rebuild (just on and off the trailer!)

Thanks guys i am going to check out that cam..

if you are looking for a great offroad cam to go in that id go for:
comp.68-232-4 extreme off road .460in.-.476ex.

it most definiately pumps up the power and has a very smooth but ready to pounce idle.

RayRay wrote:if you are looking for a great offroad cam to go in that id go for:
comp.68-232-4 extreme off road .460in.-.476ex.

it most definiately pumps up the power and has a very smooth but ready to pounce idle.

Agree. It does have those qualities but with that much valve lift you can't use the stock valve springs.

I have my motor almost built. And a guy just told me that i need a differnt computer to run this motor.. I haven't read anything about that. Is this true? Its going in a 93 yj. With a 5 speed trans. Thanks guys.. I did go with a stock cam. But new. Every cam i was looking to get was on back order. So stock it was..

Anybody know? Thanks

Untrue. Stock PCM is fine however you could add a map adjuster or piggy back controller to tune your WOT a/f's if you wanted to

Your stock computer will be fine. I do recommend larger injectors. You can control the open loop AFR with a MAP sensor adjuster or a fuel pressure regulator.

Thank you guys. I am putting in the ford injectors. What should the fuel pressure be set at? If i get a regulator..

no need for an adj fpr with the larger ford 24# injectors.

yj-woody wrote:Thank you guys. I am putting in the ford injectors. What should the fuel pressure be set at? If i get a regulator..

I'm running the stock computer, stock FPR, and Ford 24lb injectors but with my homebrew MAP adjuster set slightly higher than stock at 5.3v. The engine pulls like a freight train all the way from 800-5200rpm with no bucking or hesitation and driveability is excellent.