Jeep Engines - Oljeep

482 MOPAR PERFORMANCE PARTSBUILDING YOUR PERFORMANCE VEHICLE INSTAGESThe large number of racing classes, sanctioning groups, andtypes of performance vehicles makes it impossible todescribe the “perfect” way to modify regular productionvehicles into competitive machines. There’s simply no onebest method. It all depends on what kind of vehicle youstart with, what kind of vehicle you want, how muchmechanical expertise you have, and perhaps mostimportantly, how much money you have to spend.Of course, if you have the money and know exactly what itis you want to do, then you’ll probably want to perform allthe modifications at one time. On the other hand, if you haveto stretch your money and like to tinker and learn as you goalong, then you’ll no doubt prefer building your vehicle insteps. Racers have been doing it this way for years.The following is a general four-step method toprogressively dial-in more performance. It’s based on the“modular” concept, whereby goals are achieved byincrements (phases). Each “phase” involves greaterperformance capability, cost and complexity. Afterward,we’ll list specific Mopar Performance engine packagerecommendations for your Jeep.Stage 1 : Induction, Exhaust and TimingStock induction and exhaust systems generally are notdesigned for performance use. They tend to restrict enginebreathing. And since engines are basically air pumps, this inturn limits performance characteristics. The first step ingetting started on the road to improved performance is toinstall “bolt-on” items such as carburetors, intake manifolds,exhaust headers and high performance computers. There’sno need to get inside the engine to install these parts, andthey allow you to rev freely to 5,000 rpm or more. Thesepieces add a significant, but limited, horsepower increase(unless further engine modifications are made).Stage 2: Cams, Valve Train and ChassisThis second phase allows the full potential to be realizedfrom the Stage 1 modifications. The idea is to install ahydraulic cam with a good mid-range power curve that hasall-around applications. By eliminating travel from thelifter, it’s possible to rev up to 6,500 rpm. Of course, as withany cam installation, it’s important to also installcompatible lifters and associated valve train components.At this point, perhaps as much as SO horsepower has beenadded over the stock engine. Therefore, a number of chassisimprovement items such as shocks, springs and tractionbars should be added.Stage 3: Advanced Engine and ChassisModificationsWe now begin adding some very sophisticated racingequipment. This becomes somewhat expensive. It takes alot !of money to rev out to the 7,500 rpm range, which iswhat things such as mechanical cams, heavy duty valvetrains, forged high compression pistons, and deep sump oilpan:.; allow. In the chassis area, one-piece axle shafts,reinforced axle housings and heavy duty transmissions andclutches should be considered. (Obviously, chassis itemswill vary depending on the type of racing you want to beinvolved in.)Stage 4: All-out Competition ModificationsThis step is for the “big shooters” who run the whole thing.Engines that operate above 7,500 rpm and chassis whichare subjected to tremendous loads require the very bestpieces and optimum know-how. Money is not an objecthere if you want to be competitive. Success requires you togo all the way, especially in paying attention to details andblueprinting specifications.MOPAR PERFORMANCE PARTS ENGINEPACKAGE RECOMMENDATIONSJeep enthusiasts will find these tips helpful in selecting themosl advantageous parts from a cost and performancestandpoint. They were developed by DaimlerChrysler andMopar Performance Parts and represent combinations ofcompatible parts best suited for given performance levels.Refer to the latest Mopar Performance Parts Cutalog formore details.2SL, Jeep 4-Cylinder Engine PackageRecommendationsStage IU n e Packaae ASet Timing for Maximum HorsepowerHigh Performance Hydraulic Camshaft - 240” (P4529656)or 248” (P4529657)Valve Seal Package (P4529661)Valve Spring -Conical (P4529215)Conical Retainer (P4529217)Low Restriction Exhaust(Estimated 10 to 20 hp gain over Stock configuration)T --n 1