Best combo for High RPM

[MN_luda]

Hello, new here but not at all new to jeeps or building engines. I do engine machining so all of that is free and the limits are endless. What im wondering, is, we are building a stroker motor for a race jeep. Circle track, usually sitting over 4,000rpm in second gear the entire race. I want to know the best (yet most cost-effective) recipe for reliable high rpm power. thanks alot!

[Cheromaniac]

You could do a copy of the 4.7L medium buck stroker recipe on my site but using the longer duration CompCams 68-239-4 camshaft. You'd need to check the piston to valve clearance though especially if you decide to use larger than stock valves in the head. Specs would be as follows:

4.7L medium-buck stroker

Jeep 4.2L crank offset-ground to 3.915" stroke
Jeep 4.0L 6.125" rods
Keith-Black UEM-IC944-060 pistons
10.0:1 CR
CompCams 68-239-4 camshaft
CNC ported HO 1.91"/1.50" cylinder head
Mill block deck 0.018"
Mopar/Victor 0.043" head gasket
0.043" quench height
Flometrics F&B 68mm billet TB
Accel 26lb/hr injectors with adjustable FPR or MAP adjuster for '87-'95 engines, Accel 26lb/hr injectors for '96-'04 engines, '01-'02 Chevy LS1/LS6 28.6lb/hr injectors for '05-'06 engines