1993 Jeep Wrangler (YJ)

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(Yea, I know square headlights)




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  Well, after a little wheeling fun at Green Acres, I started to notice a squeak, squeak, squeak.  Guess what I found, yep a bad front drive shaft U-Joint, the one hard to get to with the grease gun, the one at the T-Case.  It now has two new freshly greased U-Joints, and no more squeak.  2012-08-18

  Well, the YJ made it home fine from the MIJC Hog Eat, but the transmission oil looks darker now and is a little lower than when I left the house. The engine burnt ~1/2 qt of oil in the 165 miles, but I did get 15 MPG though.

The 4.0 has the new high volume oil pump, water pump and timing set as well as valve cover. It will need the strocker parts and a new exhaust manifold/header though. The tranny will clearly have to be gone through, and I think the new noise I was hearing was the TC fins/vanes loose.

The 1990 318 from a Dodge W250 has 102K miles on it and has a lot of carbon build up in the exhaust ports. The crank turns but not a full 360, soaking the rings now to free it up and hopefully do a compression test. It will likely need a good head job at a minimum, as well as a good cleaning. I have the complete truck wiring harness, computer and dash, so adapting it's TBI should be somewhat simple. The tranny fluid looks nicely red, and it's a 4 speed OD which is a nice plus. The A518 is however 9" longer than the TF999 in the Jeep. But with the NP231 (which will bolt up to the A518) has the SYE, so the yoke is only 3.5" further rearward than the stock Jeep's ride height location.

Cost wise I suspect it might be a draw, unless I have to go into the block or tranny of the 318/518.

The 1993 Jeep Wrangler's 4.0-liter was rated at 180 horsepower at 4,750 rpm with 220 ft-lbs of torque at 3,950 rpm, redline 5250rpm. (I've also seen spec.'s of 190 horsepower at 4,600 rpm with 235 ft-lbs of torque at 3,200 rpm.)
While the 1990 Dodge's W250 5.2-liter produces a 170 horsepower at 4,000 rpm with 260 ft-lbs of torque at 2,500 rpm.

So it's 20 less horsepower, but 25 more ft-lbs and thier at a lower rpm where they are needed for off road fun.
Note that a 4.6L Low-buck, low CR "rockcrawler" is 231 horsepower at 4,400 rpm with 327 ft-lbs of torque at 2,000rpm.

The V-8 torque will likely eat the Rear Dana 35 alive, but you know the 4.6 stroker will do it even faster.


  Well yesterday the Jeep Transmission gave up the battle, not gradually, but all at once. I knew it was not in good shape but didn't expect it to go all at once. I think it's actually the Torque Converter that bit the dust. I didn't make it home, but did cost the Jeep into my buddies Body Shop Parking Lot. I went back with the Trailer and brought the Jeep home to start the "Transmission Job". I will not only rebuild the tranny, but the motor and do the needed body repairs. I've looked at how I want to "tube" my front fenders. I plan on using 1" square tube rather than the normal round. It should go well with the YJ's square design. Made good progress and spent 7 hours on disassembly.  2012-08-29

  If I go with the 4.6L Low-buck, low CR "rockcrawler", here is the start of the shopping list:

Jeep 4.2L 3.895" stroke crank (Scat 942010)  -  $434.99 at Jegs
Jeep 4.2L 5.875" rods  -  $29.99 ea, or $179.94 at Quadratec
Keith-Black Silvolite UEM-2229 +0.030" bore pistons  -  $236.95 at Summit
     (Alternate Sealed Power Z677AP30 Piston  -  $33.99 ea, or $$203.94 at Summit
Increase piston dish volume to 30cc 8.8:1 CR  -  $?
Crane #750501 192/204 degree camshaft  -  $245.00 at SummitRace-Mart

Donnelly Automotive Machine shop engine quote:
$125.00  -  Boil & Clean Block, Ready for Cam Bearings
$65.00  -  Install Cam Bearings
$125.00  -  Bore for 0.030" Pistons
$75.00  -  Mill block deck 0.035"
$120.00  -  Head Valve Job
$57.50  -  Mill Head Surface
  OK, deciding on a the particular "recipe" for the Stroker was a little more complex than I thought.  Thanks to Cheromaniac and others over at Jeep Strokers!

Here is where I believe I need to be:
  -  3.905" - Bore (30 over)
  -  9.447" - Deck Height (not milled)
  -  3.895" - Stroke, Jeep 4.2L 3.895" crank
  -  6.125" - Connecting Rod, Jeep 4.0L
  -  1.353" - Pin Height (Keith-Black Silvolite (UEM) forged stroker IC944 Pistons, 21cc dish volume)
  -  0.051" - Compressed Head Gasket Thickness
  -  0.0215" - Deck Clarence
  -  0.0725" - Quench Height
  -  58cc - Increased Head Combustion chamber
  -  Comp Cam 68-232-4, Duration 250/256, Lift .460/.476 camshaft (Intake valve Closing Value 55)
  -  HO 1.91"/1.50" cylinder head (Ported & Polished?)
  -  Ford 24lb/hr injectors with adjustable FPR (Part no. FMS-M9593-A302/Venom #735-HP-624-8 & Hesco HES9195FR)  -  $225.99 at Jegs or $219.99 at TRE  &  $179.00 at HESCO
  -  62mm Throttle Body  -  Leigh Performance Machine
  -  9.16 - Static Compression Ratio (SCR)
  -  7.86 - Dynamic Compression Ratio (DCR)
  -  89 - Targeted Octane rating
Not sure where the HP and Torque will end up, but I suspect somewhere close to 240/315 area.
  Parts On Order  (all prices include shipping, taxes, etc...):
304 STAINLESS STEEL JEEP SINGLE MANIFOLD 1991-00 4.0 L # PH-051 - eBay $130.00
4.0L Performance Valve Springs & Retainers #HESSPRSS6 - Hesco $155.72
Jeep 4.2L 3.895" Crank & Bearings - Donnelly Automotive Machine (Carquest) $245.00 (est. ~270)
6.125" - Connecting Rod, Jeep 4.0L - Donnelly Automotive Machine (Carquest) $0 parts, machining only (est. ~300)
Keith-Black Silvolite (UEM) forged stroker IC944 Pistons, 21cc dish volume (30 over) & Rings - Donnelly Automotive Machine (Carquest) $180.00 (est. ~130+64)
Engine Gaskets & Seals Set - Donnelly Automotive Machine (Carquest) $231.18
Cam Bearings - Donnelly Automotive Machine (Carquest) $22.87
Head Seat Rings & Freeze Plugs - Donnelly Automotive Machine (Carquest) $24.60
Freight and Tax - Donnelly Automotive Machine (Carquest) $85.77
K&N PS-2004 - K&N Pro Series Oil Filters - Summit Racing $5.95
COMP Cams SK68-232-4 - Xtreme 4x4 Cam and Lifter Kit - Summit Racing $229.95
COMP Cams 104 - COMP Cams Engine Assembly Lube - Summit Racing $6.95
COMP Cams 159 - COMP Cams Engine Break-In Oil Additive - Summit Racing $10.95
E3 Spark Plugs E3-58 - E3 Spark Plugs - Summit Racing $5.99
Summit Racing Delivery and Handling Charge $12.95
Rugged Ridge Jeep Air Intake System Part #17750.04 - AutoAnything $161.46
Rugged Ridge Jeep Covers Part #13321.72 - AutoAnything $93.46


Parts have been arriving.  I now have the following:

New (made in china) Exhaust Header

Performance Valve Springs & Retainers

K&N Pro Series Oil Filters

COMP Cams SK68-232-4 - Xtreme 4x4 Cam and Lifter Kit

COMP Cams 104 - COMP Cams Engine Assembly Lube
COMP Cams 159 - COMP Cams Engine Break-In Oil Additive
E3 Spark Plugs E3-58
Rugged Ridge Jeep Air Intake System Part #17750.04
Rugged Ridge Jeep Cover

Still waiting on the Engine Block, Head and Tranny Shops to complete their parts.



Parts On Order, Engine and Chassis  (all prices include shipping, taxes, etc...):

Crank Position Sensor - Part No: 55125.05
Throttle Position Sensor (TPS)- No: 55123.01
Map Sensor Quadratec Quadratec Part No: 55122.2001
Transfer Case Select Switch, (4) Ports - Part No: 52247.00
Manifold Tem Sensor/Air Charge Temp Sensor - Part No: 55121.00
Engine Mount Kit - Part No: 56003.03
Performance Distributors Firepower Ignition Kit - Part No: 17610.60X
JKS Manufacturing Quick Disconnects - Part No: 16060.0X
Windshield Hinge Set in Black - Part No: 23002.08
Smittybilt Hood Catch Kit in Black - Part No: 13004.0402
Old Man Emu Front Nitrocharger Shock Absorber - Part No: 16091.0160
Old Man Emu Rear Nitrocharger Shock Absorber - Part No: 16091.0161
Old Man Emu Nitrocharger Steering Stabilizer - Part No: 16091.2000
Fuel Tank Vent Hose - Part No: 51307.03
Fuel Filler Hose - Part No: 51308.06
Brake Pedal Pad - Part No: 55003.03
Bestop Sport Bar Cover For 92-95 Jeep Wrangler YJ, Black - Part No: 24043.15


Standard Motor Idle Air Control (IAC) Valve

Chassis Paint Kit, Epoxy, Satin Black

  Rather than buying new rods, Since I'm back to stock 4.0 rods, and with the condition mine are in I'm going to save a few bucks, hopefully.
I've now learned (based on others bad luck) that with the IC944 Pistons in order to prevent piston damage, "The balance pads on the small ends of the 4.0L rods need to be ground down so that there's enough clearance for the IC944 pistons to rock on the piston pins."
Fortunately I learned this information just in time, before the rods are installed on the pistons.
Also ordered the AEM 30-4100 Digital Wideband Air Fuel Ratio UEGO Controller.

I picked up the Transmission from the shop on Friday (2012-09-28).  they also did the vent relocation for me while they were working on it.  It's now fully rebuilt, with a shift kit and a new Torque Converter.

  Picked up the Crank, bearings, rings and new front brake lines.  the pistons are in and the shop is now ready to install them on my new rods (after making sure they have enough small rod end clearance).  2012-10-02

  Donnelly Machine, called and the rods are in the pistons, so I went and picked up everything, and paid the bill.  Everything looks good, no machining to the rods small end was required to fit the pistons, so that was good.  Now to start the engine re-assembly.

$180.00 - Valve Job
$48.00 - New Valve Seats
$47.50 - Mill Head (0.006)
$125.00 - Degrease, Block, Head, Intake
$125.00 - Bore Cylinders (0.030)
$65.00 - Install Cam Bearings
$10.00 - Install New Freeze Plugs
$45.00 - Fit Pins
$60.00 - Rod check and Truing
$60.00 - Machine Head for Hesco Springs
$2.00 - Haz Mat
$767.00 - Total Labor

  Well, today I was going through the parts inventory and browsing the manual making sure I was ready to start the re-build.  While checking parts, I discovered I had the wrong pistons.  I ended up with my first recipe attempt pistons that required the 4.2L rods and piston dish machining rather than the final selection that used the 4.0L rods and had a larger factory dish.  So I'll return these pistons and rings and have the rods removed and installed on the correct pistons that the shop already has on order.  Donnelly has been great and I don't fault them they are helping a lot.  I also received the new Venom fuel injectors and the Air/fuel Ratio Gauge as well as the push rod length gauge needed to select and then order new push rods.  You can also see my old dirty problematic IAC valve and the new one in the first picture.  2012-10-04

Resulting Engine build Specifications:
  -  3.905" - Bore (30 over)
  -  9.450" - Deck Height (not milled, measured by machine shop)
  -  3.895" - Stroke, Jeep 4.2L 3.895" crank
  -  6.125" - Connecting Rod, Jeep 4.0L
  -  1.353" - Pin Height (Keith-Black Silvolite (UEM) forged stroker IC944 Pistons, 21cc dish volume)
  -  0.041" - Compressed Head Gasket Thickness
  -  0.0245" - Deck Clarence
  -  0.0655" - Quench Height
  -  57cc - Head Combustion Chamber (Head milled 0.006", need to measure to veify)
  -  280 cu.in. / 4.6L
  -  9.38 Static Compression Ration (SCR)
  -  8.05 Dynamic Compression Ration (DCR)
  -  89, Likely required Octane
  -  240/315 Likely HP/TQ Ratings

  Well, the shop called, and they can't get the IC944 Pistons for 4+ weeks.  So I've had to order them else where (slightly more expensive) and will take them in to the shop when they arrive.  Still doing a little cleaning and painting on the Engine and parts.  2012-10-09

Well, discovered I had the wrong main bearings as well.  So when the Icon pistons arrived today I took them and the incorrect main bearings to the shop and hope to have everything by Friday.  Also the standard rear main seal in the gasket kit didn't have the needed ears, so I've ordered a correct one of those as well.  2012-10-10

  The New pistons arrived Wednesday, and today (Friday) I picked them up from the machine shop after they removed the wrong pistons, and machined the small ends of my rods to provide clearance to the bottom of the piston face (due to the short pin height pistons).  I also picked up the correct main bearings and a few more items like a new Alternator while I was out.  Seems my old one, in addition to being salt corroded, had a cracked housing, figured change it now rather than later.  Now to start the Engine Assembly, that is now that I hopefully have everything I need.  2012-10-12

Well, after a few phone calls and e-mails, I've discovered that the ICON IC944 Pistons (P/N IC944.030) I'm using are indeed Forged from 4032 Alloy rather than what ICON's WEB Site and Summit had listed as 2618.  So after some good guidance form the guys over at JeepStrokers.com, and confirmation from ICON, my recommended clearance range specification is .0025 to .003.  With my bore being 3.9050" to 3.9055" and the Pistons being 3.9023" to 3.9028", I will have to ensure I properly fit the pistons to the cylinders to keep a proper clearance.  2012-10-16