eugenebuilt 4.6L project
Posted: March 9th, 2026, 11:21 am
Got the bug and started a 4.6L build, my first stroker.
Starting details below, greatly appreciate any kind comments suggestions guidance or questions. I hope something in my project thread supplements all the great guidance on this site to help someone somewhere with their build.
2000 TJ 190,000 miles. Picked this up for super cheap with a blown engine in August 2025. After sitting on the side of my house for several months I decided it will have to be a stroker. Came with 6” short arm lift, looks to have all the right parts in all the right places, sye, geared 4.56, etc etc. Engine was clanking pretty good when bought it and towed it home and then later after starting it a couple times exploded oil and coolant from the rear of the block and seized. Good bones. Needs work. Fine.
Donor: found a complete 2004 WJ w 190k miles for super cheap, I mean stupid cheap. Starts. Drives. Idles. Front end wreck. Salvage title. Fine. Made my $$ back selling parts while I pulled the engine. Stripped a few more parts. Had the carcass hauled away.
WJ Engine: Tear down was exciting from the start when I found a TUPY under the muddy valve cover. Obvious signs of hasty poor rebuild. Timing chain cover, oil pan, and valve cover bolts were mostly only hand tight. WTF. Deck looks filed. Cylinder walls look great though. Cylinder 5 girdle bolts were in bottom of oil pan. Cam lobes had uneven wear. Crank and rod journals and bearings look great. Piston skirts show wear, rings look good. Head gasket potentially blown between cylinders 3&4, valves badly pitted, wide valve seats. Head has been to shop for vat/mag. Good core, Engine currently at machine shop for vat/mag.
4.2L Crankshaft: pulled from a 86 CJ parts engine having 160k miles. Journals show light wear, can slightly feel ridges but no fingernail catch. Machine shop says it’s a good core, buy +010 bearings. Crankshaft is at machine shop for grind as of this post, then will go for balance after parts come in.
Stroker plan:
Block: +.030 over, deck height tbd depending on pistons
Crankshaft: cast #3235477 +010 - obtained
Pistons: IC944.030 Icon forged -21cc dish - on order^see note
Piston rings: 40514CP.030 Mahle plasma moly - not ordered yet
Head gasket: C5987-027 Cometic - not ordered yet
Rods: SIR6123JP Eagle forged press fit 6.123 - shipped
Main/rod bearings: +.010 over - shipped
Camshaft: 68-232-4 CompCams - not ordered yet
Lifters: CCA-31303016 CompCams DLC - not ordered yet
Rockers: TBD
Valve Train: HES40VSRK HESCO performance valve/spring kit
SCR: Targeting 9.65-10.05 depending on a couple variables tbd
Quench: keeping this in the .041-.045 range
Combustion volume: measured 55.9cc
^IC944.030 note: looks like I picked a precarious moment to select this piston and make this order. Based on several phone calls with dealers and the manufacturer (UEM) it appears the ICON and KB 1.353 lines may potentially be in run-off. UEM says the IC944.030 are superseded by IC10181.030. A couple differences on this new part #: 1) greater compression height at 1.363 and 2) rings went from SAE to metric. Timing is precarious because dealers don’t have new part number online nor in their catalogue, so I can’t order from a dealer until they connect the dots. UEM quoted $695 for the new part. UEM showed 1 set of IC944.030 on the shelf at the GA location. So I called a dealer and placed an order which prompted the superseded notification which I had to request the dealer to override and direct the order to GA location. This was on 3/6/26 and order is pending as of this post, not yet shipped. So we’ll see if I get my hands on potentially the last ever set of IC944.030, or if I change to the newer IC10181.030, or choose a different piston. A potential benefit (depending on how you see it) of the newer IC10181.030 is the +.010 compression height as compared to the IC944.030 which means no need to mill .010 off the deck. Looks like new part will cost more but save $$ at the machine shop. Feel free to comment on this if you have authoritative details on the topic of Icon and KB 1.353 series potentially sunsetting. Or let me know if I’ve misunderstood and reality is something different. Here is UEM URL for 10181.030: https://uempistons.com/product/25293/En ... l=Wrangler
You may have gathered from above that I was thrifty on the TJ, engine, and crank which allows me to be a bit spendy on the engine. Your build may differ in budget, available parts, target SCR, etc. At the end of the day I should have a running stroker for less than $5k including the cost of the lifted TJ. Will still need other work after I get it running including new tires, windshield, headlights, vinyl floor swap, other unknowns, etc, etc.
Some variables such as pistons may change in the coming days/weeks, primarily the pistons depending on what I on sends me. I’ve considered alternatives to the Icon +.030 such as in-stock IC944 at +.020 or +.040 over, or in-stock KB hypers, or DSS. I reached out to Mr. Pottinger by email to learn about his services, I imagine he’s a busy man so I ordered from Icon anyways, could still work out if he gets back to me before the Icons ship. I considered LS swap, turbo, etc instead of stroker but wanted to keep it somewhat simple. So the above build plan is what I’m excited to build and share here.
More details to follow as I make progress, please be patient with my updates. Above describes my progress since August 2025, 6+ months and I’ve barely started. The project will be slow going. Again, your kind comments and guidance are welcome.
Starting details below, greatly appreciate any kind comments suggestions guidance or questions. I hope something in my project thread supplements all the great guidance on this site to help someone somewhere with their build.
2000 TJ 190,000 miles. Picked this up for super cheap with a blown engine in August 2025. After sitting on the side of my house for several months I decided it will have to be a stroker. Came with 6” short arm lift, looks to have all the right parts in all the right places, sye, geared 4.56, etc etc. Engine was clanking pretty good when bought it and towed it home and then later after starting it a couple times exploded oil and coolant from the rear of the block and seized. Good bones. Needs work. Fine.
Donor: found a complete 2004 WJ w 190k miles for super cheap, I mean stupid cheap. Starts. Drives. Idles. Front end wreck. Salvage title. Fine. Made my $$ back selling parts while I pulled the engine. Stripped a few more parts. Had the carcass hauled away.
WJ Engine: Tear down was exciting from the start when I found a TUPY under the muddy valve cover. Obvious signs of hasty poor rebuild. Timing chain cover, oil pan, and valve cover bolts were mostly only hand tight. WTF. Deck looks filed. Cylinder walls look great though. Cylinder 5 girdle bolts were in bottom of oil pan. Cam lobes had uneven wear. Crank and rod journals and bearings look great. Piston skirts show wear, rings look good. Head gasket potentially blown between cylinders 3&4, valves badly pitted, wide valve seats. Head has been to shop for vat/mag. Good core, Engine currently at machine shop for vat/mag.
4.2L Crankshaft: pulled from a 86 CJ parts engine having 160k miles. Journals show light wear, can slightly feel ridges but no fingernail catch. Machine shop says it’s a good core, buy +010 bearings. Crankshaft is at machine shop for grind as of this post, then will go for balance after parts come in.
Stroker plan:
Block: +.030 over, deck height tbd depending on pistons
Crankshaft: cast #3235477 +010 - obtained
Pistons: IC944.030 Icon forged -21cc dish - on order^see note
Piston rings: 40514CP.030 Mahle plasma moly - not ordered yet
Head gasket: C5987-027 Cometic - not ordered yet
Rods: SIR6123JP Eagle forged press fit 6.123 - shipped
Main/rod bearings: +.010 over - shipped
Camshaft: 68-232-4 CompCams - not ordered yet
Lifters: CCA-31303016 CompCams DLC - not ordered yet
Rockers: TBD
Valve Train: HES40VSRK HESCO performance valve/spring kit
SCR: Targeting 9.65-10.05 depending on a couple variables tbd
Quench: keeping this in the .041-.045 range
Combustion volume: measured 55.9cc
^IC944.030 note: looks like I picked a precarious moment to select this piston and make this order. Based on several phone calls with dealers and the manufacturer (UEM) it appears the ICON and KB 1.353 lines may potentially be in run-off. UEM says the IC944.030 are superseded by IC10181.030. A couple differences on this new part #: 1) greater compression height at 1.363 and 2) rings went from SAE to metric. Timing is precarious because dealers don’t have new part number online nor in their catalogue, so I can’t order from a dealer until they connect the dots. UEM quoted $695 for the new part. UEM showed 1 set of IC944.030 on the shelf at the GA location. So I called a dealer and placed an order which prompted the superseded notification which I had to request the dealer to override and direct the order to GA location. This was on 3/6/26 and order is pending as of this post, not yet shipped. So we’ll see if I get my hands on potentially the last ever set of IC944.030, or if I change to the newer IC10181.030, or choose a different piston. A potential benefit (depending on how you see it) of the newer IC10181.030 is the +.010 compression height as compared to the IC944.030 which means no need to mill .010 off the deck. Looks like new part will cost more but save $$ at the machine shop. Feel free to comment on this if you have authoritative details on the topic of Icon and KB 1.353 series potentially sunsetting. Or let me know if I’ve misunderstood and reality is something different. Here is UEM URL for 10181.030: https://uempistons.com/product/25293/En ... l=Wrangler
You may have gathered from above that I was thrifty on the TJ, engine, and crank which allows me to be a bit spendy on the engine. Your build may differ in budget, available parts, target SCR, etc. At the end of the day I should have a running stroker for less than $5k including the cost of the lifted TJ. Will still need other work after I get it running including new tires, windshield, headlights, vinyl floor swap, other unknowns, etc, etc.
Some variables such as pistons may change in the coming days/weeks, primarily the pistons depending on what I on sends me. I’ve considered alternatives to the Icon +.030 such as in-stock IC944 at +.020 or +.040 over, or in-stock KB hypers, or DSS. I reached out to Mr. Pottinger by email to learn about his services, I imagine he’s a busy man so I ordered from Icon anyways, could still work out if he gets back to me before the Icons ship. I considered LS swap, turbo, etc instead of stroker but wanted to keep it somewhat simple. So the above build plan is what I’m excited to build and share here.
More details to follow as I make progress, please be patient with my updates. Above describes my progress since August 2025, 6+ months and I’ve barely started. The project will be slow going. Again, your kind comments and guidance are welcome.