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Performance 4.0 build

alex22

NAXJA Forum User
So I picked up another XJ a month or so ago that needed a new head, its an 01 and the head was not repairable. I had planed on just doing a quick head swap, but the more I looked the less I liked so out came the engine. The cam was starting to wear, rings were shot, expansion plugs were almost rotted through, pistons were scuffed badly and the timing chain was slopped out. The crankshaft main journals were at minimum spec, main housing bores were at maximum and the factory put in a half set of .001 under bearings. But other than that it was great...

New parts and labor:
Clean and magnaflux.
Block was align honed to minimum spec so I can use STD bearings without Excessive oil clearances.
Balanced rotating XXXembly.
ARP rod bolts.
.020 over Speed Pro pistons
Block decked to bring the pistons to about .005 in the hole for 9:1 compression and tighten the squish.
Comp Cams 68-232-4
Pre 1997 timing set and bolt with spring loaded pin.
Mopar performance valve springs & retainers
New head casting with some porting and chamber cleanup and performance valve job.
Ebay SS header and high flow precats.
Magnaflow high flow cat and Dynomax catback
AFE intake.
4 hole injectors.

Will moving the IAT sensor into the intake tube/airbox or an adjustable MAP be enough to keep the A/F ratio correct with the breathing mods?

Will 19lb injectors be enough for this?

Can the Mopar Performance valve springs and hardened locks be used with the late style 3 groove keepers or do I have to get the older style valves and use single groove hardened keepers?

~Alex
no, this will not become a stroker.
 
You still have a 4.0L displacement. The injection system will not need to be modified. The 2000 doesn't have 19lb injectors, but 22.5lbs. You need the older style valves to use the MP locks. I would also do a 30* back cut on the intake valves. I would also recommend using a solid pin on the cam instead of the pin and spring setup. If you have the time you could polish the rods and clean up the crank a bit.
 
Thanks for the correction on the injector rate. Now that I need to get new valves in order to run the Mopar spring package I'm going to look around the shop for a set of LS valves.
I balanced the crankshaft within race spec the other night (it was only off a few grams to start with.) The oil holes are going to get chamfered, rods and mains are going to be polished. I'm not going to worry about the rough casting of the crank though. Polishing and shot peening the connecting rod beams won't take too long and I haven't resized them yet so its not too late.

~Alex
 
If you are going with LS valves it may be cheaper just to do the whole valve and spring setup based on them vs. Mopar Performance springs. You may be able to run stock 3 bead locks with the MP retainers. IIRC they are the same degree, but I don't remember 100%. I doubt smoothing out the crank will help performance at this level (or rather any 4.xL build for that matter), but it will make oil shedding easier. You are balancing the rods and pistons as well, correct?
 
The piston and pin assemblies came out of the box at -0 to +1 gram of eachother. I'm going to match the weight of the big and small ends. The 3 bead and the single bead locks are both 8*. 3 bead locks aren't the best for RPMs but would probably work on this cams power band (800 to 4800.) I'll have to do a test fit with LS valves and springs on a junk head. As much as I dont want to do another valve job it wouldn't be so bad since the parts will be free.

~Alex
 
3 bead locks aren't the best for RPMs but would probably work on this cams power band (800 to 4800.)
Lol. Its not like you can spin these engines much over 5500 rpm.
 
I finished up an engine for my cousin a few weeks ago so its back onto my own.

My cousin's:
Dart block, Eagle 427 stroker crank and rods, Mahle pistons, ported heads with dual 450 carbs, solid flat tappet and 10.3:1 compression. 537 Hp @ 5500 and 548 ft*lbs @ 4600.
1715DEE3-EFD6-43C8-B7C4-34D781E95E4C-284-00000062A08F875B.jpg



My 4.0 so far:
0331 head, the top of the head was not cracked between #3 and #4, but...
FFFED33F-8F4E-4520-B9C9-92AAFC909E2F-284-00000062D03E1400.jpg


Replacement head from ATD Diesel, new casting.

E8142444-67C7-401E-9495-A7FCB6312F21-284-000000673E78EC95.jpg


Gave it a performance valve job.
898ACBE5-AA70-459B-BB0C-0B77AB341AFA-284-00000062E801B773.jpg


Intakes and exhausts cut.
63494F88-FBBB-41BF-A862-496679844B98-284-0000006353E26D22.jpg


Always check concintricity.
9210706D-D375-437A-9ED3-2D1BB0EBAB69-284-00000063457A8F4B.jpg


Placement of the seat to the valve. The intakes were backcut to 34* and 19* and the exhaust valves to 30* (forgot the pics of those.)

5845B774-B1B4-40EF-B72D-F555137B92CA-284-0000006362C4DC79.jpg


The ports and chambers were a bit rough and I spent a few hours with the die grinder. I flowed it and compared it to a factory 0331 head with only 7000 miles on it which came through the shop a few years ago. I flowed that one on my own time just to see how it was. This head now flows about 10 CFM better than the factory head.

7ED023A9-50B7-4A9C-90C8-3A917E38259C-284-000000631DC427B8.jpg


Head on the bench, I forgot to print out a report though.

740F91FF-8342-4D5F-A0CE-5DD578017591-284-0000006FE9C89A96.jpg


Now onto the block....

After a quick hone I did a test fit with all of the pistons to determine how much to deck it. Now on the resurfacer, I took about .025 off the block to put the pistons between .010 and .005 in the hole. I had to cut .005 off of the deck just to clean it up, the shiny parts in this pic are the areas that the cutter hit first.

CBC28A3E-BCC0-496A-93A5-C4DD0E884629-284-0000005888444BDF.jpg


All finished up in the hone.

E6B85DC5-C3FE-4D2E-9E7A-BCA0A1F8BE35-284-000000587A178028.jpg


And how it sits as of now. Rods maged, ARP rod bolts, resized, weight matched and balanced, checked for straightness, hung the new pistons, checked piston ring end gap, align honed, clearances checked final cleaned and painted.

776D77FA-1041-4E54-8B92-B60FAC7DCB19-284-000000584CA73F20.jpg


Its almost too pretty to put back into the XJ

E4D73E3F-E0A2-40B5-AD88-6BD0359CA5FA-284-0000005858FC1794.jpg


And now that I'm back in school Its going to be slow going for this 4.0

~Alex
 
Springs and retainers are here.
Comp Cams 26125 springs meant for a 4.6 mustang
Comp cams 761 retainers meant for a 5.7 Hemi
Factory 3 groove keepers
Manley spring seat cutter: 41824
Thanks to Talyn and Lafrad for the combo.

Install Height with this setup is 0.060 tighter than using the factory Jeep retainer. I didn't check spring force on the spring on the seat or full lift yet.

Spring seat cutter in action.
2577FCA9-A07E-4C68-BDB7-2F8922513F78-2577-000002E30CED5C99.jpg


Before, during and after in the VGS-20
5A88CC9F-B171-4BD9-8084-558CD2CAF7C1-2577-000002E31377081F.jpg


Resurfaced the manifold surface.
44F7ECE4-AFC0-44B3-90E8-4A77EBF9B818-2577-000002E3056A945C.jpg


Cut 0.008 off of the deck of the head.
8D07FFF5-0F74-4A58-B05F-60F626F07EBA-2577-000002E2FB0680C2.jpg
\

~Alex
 
Its all together now, smoke checked, primed and the cam sensor has been clocked.

I'm bringing this thing home this weekend. Its going to need some new injectors, the ones I took out didn't look too good and were the single hole design. I was keeping up with the "Precision Injector" thread from the supplier on eBay but I can't remember what the final verdict on that seller's quality was. Does anybody have an update for me or another source for the multi hole injecots?

~Alex
 
I'm running the green 4 hole precision injectors. (For my 01.) I had a leak down issue, but they sent me a new set, and they work awesome now. Holy crap, great work.

Is this kind of work really hard? Im not a machinist, I'm great at working on my jeep, but engine stuff is like voodoo magic to me.

You mentioned highflow precats, and maybe a new exhaust manifold? I'd like to know what you did, I'm looking for power options for my 2001.
 
Can you post your head flow chart? What size valves?

740F91FF-8342-4D5F-A0CE-5DD578017591-284-0000006FE9C89A96.jpg
 
Wow this sounds spot on to the build im about to do. Definatly keeping my eye on this thread. great work so far !
 
I'm running the green 4 hole precision injectors. (For my 01.) I had a leak down issue, but they sent me a new set, and they work awesome now. Holy crap, great work.

Is this kind of work really hard? Im not a machinist, I'm great at working on my jeep, but engine stuff is like voodoo magic to me.

You mentioned highflow precats, and maybe a new exhaust manifold? I'd like to know what you did, I'm looking for power options for my 2001.

Most of the info I found about precats and headers for the 01 was from this thread.
http://naxja.org/forum/showthread.php?t=1078435
I was going to pick up some stainless headers from ebay but plans changed and I'm using the stock exhaust again.
I think these were the cats I was going to use.
http://www.partstrain.com/store/det...er/2001/Limited/6_Cyl_4-dot-0L/EAST20376.html

Can you post your head flow chart? What size valves?
Marty, Here are the flow numbers. The 0331 head I'm comparing the flow to only had about 7000 miles on it, it had a quick clean and that was all. I didn't flow the replacement head as cast but it was quite a bit rougher than a factory head, especially on the short turn radii, The valve job was a wide with interference seating angles. Stock valves with a 32* backcut on the intakes. IIRC intake seat is 38*/45*/52* and the exhaust has radii above and below the 45*. My goal was to make the replacement head slightly better than an OEM casting.

atdvsoem0331report.png


Light blue and red are the replacement head.
atdvsoemgraph.png


Wow this sounds spot on to the build im about to do. Definatly keeping my eye on this thread. great work so far !

Thanks, the whole Jeep will probably come up for sale...

As far as doing the labor, I started sweeping the floors in an automotive machine shop about 7 years ago and it was just about all OJT for me. I'd say its more about the attention to detail and measurement than "hard work" because there's always something looking to kick you in the dick if you're not looking for it. The majority of the judgement calls and parts selection was done by the boss and a few of the older guys I worked with, I ran the machines and assembled. Its an interesting trade if you're looking to get into it, there are a few schools around the country for this specialty job.
That being said I'm back to school again for a BSMET and working as manufacturing engineering intern, I was at the engine shop for almost 7 years to the day.

Here's where I left it Sunday night, the 4 bolts from the trans to block are in and torqued and its resting on random bolts for the engine mounts. No idea where the correct bolts went, are they anything special or can I use some 7/16" x 5" bolts with washers and a locknut?
Does anybody know the term for the opposite of a turd in a punch bowl?
imagelcih.jpg
 
A Diamond in the Rough?

Thanks for the flow numbers. You squeezed a bit out of them.
These heads flow suck at best.
 
A Diamond in the Rough?

Thanks for the flow numbers. You squeezed a bit out of them.
These heads flow suck at best.


I forgot to mention that both heads were flowed over a 4" bore adapter. These heads actually flow very nice for their size and even do well when compared to a Chevy Vortec 350 head. For when the HO head was first designed its actually a very nice port.
 
Made some more progress this weekend.
Stock exhaust manifolds were resurfaced.
imageosyx.jpg


Injectors from PrecisionAuto on eBay. That guy ships fast, I ordered Tuesday at 5 and had them on Saturday.
imagegfl.jpg


The injectors have a sleeve of the DEI 3/4" insulation on them and the factor insulation mat is cleaned up as best as possible. I slipped the extra DEI insulation over the fuel feed line and I'll probably pick up another 3 feet of it to extend further past the pre-cats, trying to prevent the common vapor lock issues.
Here's how I left it Sunday night.
imageaqi.jpg


~Alex
 
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