RaceJeep's engine is burning oil, like about 1 quart/100 miles. It has 165,000 miles, most neglected by PO. Could be rings or valve stem seals. Instead of replacing the valve stem seals or trying a new head and all that cost and labor, We decided to build a new engine.
If this goes well, the plan is to 'break it in' in RaceJeep with the M62 Supercharger 5-6 pounds boost and get the tune right, then add a M90 Supercharger and more boost! Up to 15 pounds boost!
If all goes well, build a 2nd of these forged 4.0L engines for our Sprintex SC XJ, BPas328xi's DD.

Reqirements-
-look stock
-Daily Drivable! long engine life
-reasonable costs, No $5,000 + dyno or trailer queen
-no aluminum head, don't like aluminum head on cast iron block (different thermal properties)
-run on stock ECU, retain cat, OBD and smog legal
-'99+ block with cam retainer plate (no spring/pin or bolt)
-NO stroker, want highest HP/TQ 4.0L (head flow sucks for 4.0L let alone 4.6L)
-Supercharger capable, 15+ pounds boost

CLICK HERE FOR MORE DETAILS and BUILD

 

Head at the machine shop this week getting built.
2.02" intake SS single groove, 1.62" SS exhaust single groove
Lunati 74814 springs, Hemi retainers 8mm 8*, Mopar Performance locks 8mm 8* single groove
Ported, Polished, cc'ed, flowed

 

Please keep us posted, sounds exciting!

 

Got a cam in mind yet?

 

head designs matter slightly less when boosted

 

Even a 5k budget won't buy you much in the way of a race motor much less parts and machine work that's needed.

Aluminum heads on a cast iron block problems......NOT been running them for many years over 35 in fact and up to 2000HP (SBC) on current engine. Don't know who told you that but they must have been smoking crack.

 

Yeah, just don't want to be a guinea pig for trying an alumn head on a Jeep I6. The 4.0L has many reliable 200,000+ mile history with iron head on iron block and very little alumn head on iron block history. How many HESCO alumn heads are out there on daily drivers? This is going to be a DD reliable high mileage engine build and not a weekend racer. Maybe an engine in the future will have an Edlebrock alumn head if it flows well and is not $2000. But right now there are NO alumn 4.0 heads available. Chevy or Ford, etc, now that's a different story.

Jones Cams 204/216 0.502"/0.519" with 1.7 rockers 113 LSA on '99+ core.

Boost will help the head flow but starting with the best you can N/A will net you the best when boosting.

Golen wants $5650 for their '99+ SC ready long block with core. This engine is my benchmark to beat.
https://www.golenengineservice.com/e...eep-long-block

And run it all on a stock ECU and pass emission.

 

I'm curious to see the flow chart on the head. do you have any for a stock head?

 

Head Flow Numbers- 0.100 0.200 0.300 0.400 0.500"
7120 0630 Head stock 66.0 128.0 179.0 206.0 219.0 Exhaust- 55.0 100.0 120.0 136.0 141.0
HO head 0331 Intake- 59.4 122.6 171.1 201.1 214.3 Exhaust- 47.1 093.4 123.3 140.9 147.0
Ported HO head 7120 68.4 132.6 185.4 213.4 216.5 Exhaust- 64.3 116.9 149.6 158.9 165.0
Ported HO head 0331 65.2 128.4 186.5 219.5 218.9 Exhaust- 56.9 096.9 123.9 140.2 148.9
Ported HO 2.02/1.60 73.9 142.4 197.8 229.8 247.0 Exhaust- 65.3 114.0 135.9 146.3 157.1
Dr.J ported 1.91/1.50 67.0 137.0 190.0 227.0 237.0 Exhaust- 60.0 101.0 133.0 164.0 182.0
Hesco head 1.91/1.50 74.0 134.0 183.0 226.0 255.0 Exhaust- 55.0 093.0 117.0 131.0 142.0
Hesco Port 2.02/1.57 61.2 116.8 164.7 205.3 235.2 Exhaust- 51.0 080.5 110.2 132.8 149.1
HO ported BV chamb 57.9 122.0 176.8 214.5 225.5 Exhaust- 49.7 091.8 127.0 153.9 165.5
Other 1.94/1.50 Chevy 177.0 214.0 Exhaust- 130.0 146.0
Ported 1.94/1.50 Chevy 185.0 216.0 Exhaust- 150.0 165.0


The RED numbers are the highest flowing at particular lift.
Valve size is also listed for head. Stock size valves if not listed.
Interesting is that even though the big valve 2.02/1.60" are 'shrouded' they do flow the most.
Even better than Dr. J, and Hesco.