Newbie checking in and ready to build!

[pma4x4]

Hey guys,
I have been surfing this site pretty much solid for the last week. I figured I should just sign up and get in on the fun.
So I picked up a spare motor top to bottom FI and all for $50.00 2 weeks ago and thought lets rebuild it. Then I thought what about a stroker? I then got lucky yesterday and scored another motor with all the rebuild parts still in the boxes for $300. I have rebuilt a couple of SBC in the past like 15 yrs ago so I crash coursed myself on the 4.0s and I think I got it pretty close.

What I want to do:
We are building our 96 XJ for overlanding. This will include cross country and up to around 3.5/4 trails. We will be towing an offroad trailer weighing around 2,000lbs in mountain passes reaching 13,000ft.

What I want out of the motor:
Simple, all around more power thru entire bandwidth and more so for hwy speeds. I still want to run off regular (US) 87 octane if possible. I currently get 18 mpg empty. I would like to keep that MPG if not gain some.

The XJs current state.
96 XJ 4dr 147,xxx miles motor still pulls strong.
AW4 (with 18k miles on rebuild)
231 SYE (this is planned to get swapped to a 242 later)
D30 front
8.25 rear 3.54s (planned 4.56s this tax return)
99+ intake mod
Fastman 62mm TB Matched thru to intake
Rebuilt and matched Ford 24lb Fuel Injectors from Performance Auto injectors.
Edelbrock Header
Gibson Snorkel
All ignition parts are Mopar and Champion Spark plugs.

I will have the 258 crank tomorrow from a friend who passed on his stroker idea, the crank is all done and still in wrap. Traded him the left over parts from the other 4.0 I got. I still don’t have 258 rods yet.

1st question,. I use just regular 4.0 pistons with a 258 crank and rods right?

2nd question, comp cam 68-232-4 a good choice?

3rd, wheres a good place to get 258 rods?

I ended up with a almost a grand worth of stuff from this guy still in the packages I just need to make sure some of the parts are good to go. I know most are perfect for the job. I may post the parts and see what you guys munch on from there. I was planning on posting my recipe this week and go from there.

[Cheromaniac]

1st question,. I use just regular 4.0 pistons with a 258 crank and rods right? That's one option. The other is to use the 258 crank, 4.0 rods, and Keith-Black 944 pistons.

2nd question, comp cam 68-232-4 a good choice? Yes. CompCams 68-231-4 also worth a look and will yield a slightly wider powerband

3rd, wheres a good place to get 258 rods? You won't need them if you use 4.0 rods and Keith-Black 944 pistons.

Check out my "recipes" to see which one most closely fits your needs.

[SilverXJ]

The 68-232-4 is a good cam, but I would recommend the 68-231-4 above it. Either way you will have to change the valve springs. And don't get Comp Cam's kit as the springs, retainers and locks won't fit the 4.0L head. Check out strokedjeep.com for a better price on the throttle body.

What is a Gibson Snorkel?

[pma4x4]

OK well some confusion I need to get figured out here.

I had bought a huge amount of parts from a guy that was on his way to building a 4.6 stroker. for what ever reason he bailed iand i got all his still new on box parts. Most of them are what i was looking at for my build. Below is my recipe for parts.

Block: 2001 #5301044 "NVH" (already have)
head: 1992 7120 with about 10K on it from ATK (already have)
Crank: 258 #3727 4 weight. rod bearings are.020, mains are .010 54mm nose (already have)
Cam: Compcam 68-232-4 (already have)
Lifters: sealed power HT-2011 (already have)
Springs: Mopar Performance valve springs #5249464 (already have)
retainers: Mopar Performance retainers #4452032 (already have)
locks: Mopar Performance locks #4529218 (already have)
timing chain: Cloyes C-3085 single roller (already have)
Pistons: Silvolite 2229 .030 with pins (already have)
rings: Hastings 667 .030 rings (already have)
gaskets Fel-pro 260-1548 (already have)
oil pump: melling M-81A (already have)

Besides the block and the crank. everything else I got from the guy for $300. I have not had the block in to the shop yet so its not confirmed whether /030 over will work. if not i will just sell these pistons cheap and buy a new set.
I dont have 258 rods yet but i am working on that right now.
was going to go with federal-mogul or clevite 77 for bearings.
Am going to port and polish the head and install the Harland sharp Rockers.


So I am pretty much looking at this combination. I think I read some where that I will need to have my pistons dished more to bring the CR down. I want to run on 87 octane.



I have seen Stroke jeeps TBs and they are not bad. some of the machining could be a bit smoother. I chose the fastman just due to the higher machine quality and overall finish.

A gibson snorkel is a "Airflow" brand snorkel. direct competitor of ARB snorkels.

[dwg86]

The federal-mogul rod bearings I used on my stroker had the notch in them that lubes the cam bearings. I don't know if the clevite bearings have the notch.

[pma4x4]

So as for the bearings do i get mains for a 4.0? I think the main bearings are the same between 4.0 and the 4.2 correct?

Rod bearings for a 4.2 if its 258 main with 258 rods?

[Exos]

You need main and rod bearings for a 4.0L. The mains are not the same for the 4.2, the lock tang is not at the same place.

[pma4x4]

Yeah I thought about last night after posting. Thanks for verifying it for me.

[SilverXJ]

I would reconsider using the single timing set. Go with a double, as they are stronger.

The Clevite rod bearings won't have the cam oiling notch unless you find some old stock. But you can modify them for it yourself. Also, King bearings are very good, but I don't know if they have the notch either.

Also, the notch lubes the cam lobes, not the bearings.

[pma4x4]

The timing set was on the chopping block the minute i saw it was single. Would prefer to use federal Bearings. just needing to find correct # for 91 newer block. I have come across alot of bearings for a 2001 4.0 and find out those bearings are 87-90 4.0 or 258s its says. The hunt for the correct federal numbers for rods and mains still continue.

[amcinstaller]

sorry to cut in, but with the 4.2 rods, would you still use the 4.0 rod bearings?

[dwg86]

Also, the notch lubes the cam lobes, not the bearings.

You are correct silver, my bad.

[SilverXJ]

sorry to cut in, but with the 4.2 rods, would you still use the 4.0 rod bearings?

Yes, the rod bearings are the same for both engines. Its the main bearings that change.

[pma4x4]

I still need to find 4.2 rods. Cheromanianc mentioned KB944s instead of 4.2 rods. Not for that $$$$! I am not running a dragster nore is it seeing a turbo or NOS.

I am just trying to pep up the power plant to make it better for towing and hiway speeds.


So all i need (besides machine work)

Main bearings for 2001 (federal)
rod bearings for any 4.0 (federal)
4.2 rods.


QUESTION
The 4.2 crank i got (3727) the nose measures 54mm. I still have to turn it down?

[Cheromaniac]

I still need to find 4.2 rods. Cheromanianc mentioned KB944s instead of 4.2 rods. Not for that $$$$!

True, the KB944's aren't cheap but they won't be much more than the combined cost of a set of cheaper hypereutectic 4.0 pistons and a set of 4.2 rods.