If you had told 20-something me that I would stop racing, only have one operational SR20-powered vehicle (an off-road buggy, no less), daily drive a RWD V8 pony car, and spend most of my free budget swapping a smog legal GM Gen III Small Block (aka LS engine) into a Jeep, that asshole that was once me would’ve laughed at you. Sorry about that, youth brings arrogance.
Nonetheless, I find myself embarking on the painful journey of not only an engine swap, but a cross-manufacturer engine swap in a street legal (mostly, don’t talk to me about mudflaps) California vehicle. While many of you may not necessarily be interested in an off-road project, there will definitely be a lot of useful information in this swap that pertains to any vehicle, and the information on a smog legal LS swap in California isn’t the most complete or current. Not doing a California street legal LS swap either? I’m sure you’ll still have plenty of opportunity to laugh at me while I shoehorn a V8 into a cramped Jeep and then attempt to convince bureaucrats that everything’s okay. Honest sir, this thing is 100% stock. Bolts right in.
Before we dive into the particulars about the “LS” swap (more on that later), it’s best I introduce you to what’s been an ongoing project for the past 4 years for me. Just because I stopped racing, doesn’t mean I’ve stopped
ruining turning perfectly good street vehicles into something the original manufacturer never intended.
My 1997 Jeep Cherokee Sport, or the XJ as its known in the Jeeping world, is a little rough around the edges, but is perfect for my intended purposes. Bought for $600 from some kid in Carlsbad (it had a smashed front right header panel, a dead water pump, and a lot of AA pamphlets in it), it was the S13 of the off-roading world when I bought it: cheap fun with enough aftermarket support to build to any level you want. Like the S13, some yahoo wrote an article about how cheap and capable they were, and finding one for a song isn’t possible anymore. Total budget so far? $4200. Hopefully it won’t double by the time I’m done. Paint? Yeah, it has some left. Straight body panels? Overrated. Air conditioning? Arctic: I may be uncivilized, but I’m not a Neanderthal.
The suspension/drivetrain on my XJ is well-sorted. Mods so far are lockers and 4.56:1 gearing for the stock Chrysler 8.25 and Dana 30, home-built truss and inner C reinforcement on the Dana 30, an Iron Rock Off Road (IRO) Rock Link long arm kit, IRO over the knuckle steering, IRO track bar (modified for zero bumpsteer with the over the knuckle steering), Rubicon Express 5.5” lift springs, home-built boomerang rear leaf spring shackles, 33×12.50×15 General Grabber X3s on beadlock wheels and Fox IFP 2.0s front and rear. Useable (i.e., tires or frame don’t act as bumpstops and the vehicle can turn full lock without contact) suspension cycles 13.5” rear and 16” front. With remote reservoir Fox 2.0 Factory Series shocks and long-travel suspension links, this XJ can maintain 40mph over large whoop sections, yet still crawl comfortably maintaining reasonable speed over the ever present pumpkin-sized rocks that present no challenge to a well-sorted rig but will beat the occupants senseless on an all-day trail. The small-ish shocks will fade on long high-speed desert runs, but these are few and far between and do not pose much of a limitation for most recreational trips.