Jeep Strokers

Completely new to anything engine internal, have been doing some reading and have some questions, looking for input on the build overall etc.

I want it to run 87 Octane

2004 Wrangler 4.0

Here is the Build I have so far

Jeep 4.2L 3.895" stroke crank
Jeep 4.0L 6.125" rods
Icon 4032 +0.030" bore pistons, dish volume 21cc
CAM- 263/267 degree camshaft LSA 114
Stock 57-58 CC Cylinder head.
Stock size 0.051" head gasket
Stock deck clearance .0215
Ford 24lb/hr injectors with adjustable FPR or MAP adjuster for '87-'95 engines, Ford 24lb/hr injectors for '96-'04 engines, '99-'00 Chevy LS1 26.2lb/hr injectors for '05-'06 engines

Calculated Static Compression Ratio = 9.24:1
Calculated Dynamic Compression Ratio = 7.39:1
Quench .0725

1. I need camshaft advice, really not sure were to head with it. Got my numbers from the Clegg Stage 1 kit http://www.cleggengine.com/stroker-kits ... t-kit.html

2. Any suggestions to improve the build? and still run 87 I.E. deck the block, use a piston with smaller cc, go .060 instead .030 etc.

3. I assume computer with the 04 will self learn?

Was going to go with RPM machine stage 3 Kit to achieve the above https://rpmmachine.com/amc-stroker-kit-4l.shtml

My input is that if your over .070 piston to head you don't have an effective quench

Decking the block, reducing the dish in the piston, and moving up to a 3.935 bore will bring the static compression up too high.

Tightening up the quench closer to .040 with a 24 to 26cc piston is the direction you want to go.

You're welcome to shoot me a call or email and I'll be happy to tell you how wonderful my stroker kits are


Russ Pottenger
Bishop-Buehl Racing Engines
531 N. Lyall Avenue
West Covina, California 91790
Cell (626) 673-2203
Email/PayPal: [email protected]

Jrama403 wrote:Completely new to anything engine internal, have been doing some reading and have some questions, looking for input on the build overall etc.

I want it to run 87 Octane

2004 Wrangler 4.0

1. I need camshaft advice, really not sure were to head with it. Got my numbers from the Clegg Stage 1 kit http://www.cleggengine.com/stroker-kits ... t-kit.html

2. Any suggestions to improve the build? and still run 87 I.E. deck the block, use a piston with smaller cc, go .060 instead .030 etc.

3. I assume computer with the 04 will self learn?

I suggest you use custom pistons & custom cam from Russ and do this:

4.6L low-buck stroker

Jeep 4.2L 3.895" stroke crank
Jeep 4.0L 6.125" rods
Custom forged +0.030" bore pistons, compression height 1.385", dish volume 25cc
9.5:1 CR (assuming 57cc chambers)
Custom camshaft
Russ Pottenger ported cylinder head (LS1 valves)
Victor Reinz 0.043" head gasket
0.038" quench height
'99-'00 Chevy LS1 26.2lb/hr injectors for '05-'06 engines

Tighten up the quench. The stroker I built had close to the same compression numbers. I could run 87 octane with no problem. With that being said I thought I would have liked higher compression. It ran good, and better power than the stock 4.0, but I always thought it lacked a little something. Tighten up the quench and you'll be able to run a higher compression, or so I'm told.

Really appreciate the advice! I have modified my build and I am Talking with Russ about assembling a kit.

Couple other questions

Which fuel injectors work with the 2004 4.0 ? I know 2003 + Motors ditch the distributor.

had these in mind https://www.summitracing.com/int/parts/ ... /make/ford

Also is it necessary to balance the rotating assembly on these motors?

Here is a very good article about compression and quench, if you take the time to read it. Explains the how and the why.

http://www.hotrod.com/articles/0311em-power-squeeze/

Ended up with the following build.

Jeep 4.2L 3.895" stroke crank
Jeep 4.0L 6.125" rods - Re-used from previous motor
Keith Black Hyper +0.030" pistons, dish volume 24cc
Moly piston Rings
CAM- 263/267 degree camshaft LSA 114 (I have the 505 Stage 1 cam)
Stock 57-58 CC Cylinder head. shaved down .006
Stock size 0.051" head gasket
Decked block to near zero .003
'99-'00 Chevy LS1 26.2lb/hr injectors for '05-'06 engines

Static Compression Ratio 9.3:1
Dynamic at Elevation 7.2: 1
Quench: .048

Yes it runs Regular gas no issues, no engine lights or quirks and it pulls MUCH better than stock so far I am very happy with how everything has turned out! Ordered everything from 505 and Rock Auto, employed a couple of local machine shops for block/head and built the engine ourselves. Have about 500 miles on the Motor so far will let you all know if it blows up!

Glad you're a happy camper and are enjoying the new-found power. Just make sure the engine doesn't blow up!