Thought some folks on here might find my little project kinda interesting.

I turned 50 this year, & with the numbers creepin up on me, I wanted to do something I've done for other folks, but never for yours truly. Build a custom vehicle for myself. A little background, I worked as a mechanic for about 20 years after high school, except for a 3 year stint as an MP at Ft Bragg, NC. My health took a huge crap in 2001, & now I'm pretty much a dude that tries to keep busy, but I'm pretty slow compared to my younger days.

I became a Jeep enthusiast, because it gets me in the Utah back country, where I'm no longer able to hike. As a way to keep life interesting, a good bud and myself, head out there twice a year, and escape.

My first Jeep purchase was an 01 Cherokee, and I did pretty good on that deal. They were, and still are cheap. The Cherokee weighs 3000 pounds. Very lightweight compared to many more modern SUVs. I've had quite a few Jeeps since, and fixed up a few to resell, & have become kind of the local expert on XJ and ZJ Jeeps. I still have the 01, because it's a very nice looking, and clean example, and I do some pretty hairy stuff in it, with the intentions of getting someplace interesting. I don't really wheel for the sake of wheeling, although I know it's a lot of fun. Just trying to preserve the vehicle. Some folks actually go wheeling & intentionally try to break their rig. That's not me at all. LOL

Well, My Cherokee XJ started to lose power, & I have the suspicion the previous owner kept it clean, but was a slacker on oil changes. A compression test revealed all the cylinders had even compression, but much lower than factory specs. A few squirts of oil in each cylinder brought the readings way up. I was also pretty sure a cracked head would make an appearance upon disassembly, so I pulled the engine and listed it on craigslist for parts. Got 300 out of it within 24 hours.



Between the compression test, and pulling the stock 4.0, I found & purchased a low mileage Corvette LS1 aluminum block, fuel injected V8, and a 4L60e automatic transmission.



The Jeep journey begins.

It was march 2014. I was ready to get started on a huge project, & even though I'm old & slow, I can work for a few hours a day, with a crapload of breaks & sitting on a trusty milk crate. Drinking lots of water is a big help. I work outside under a big ol carport that's built kinda like a picnic shelter at a state park.

First step was ordering some parts. Now, I'm not wealthy, and I sold a lot of stuff, & even borrowed a little money to make this happen, but I had to be pretty conservative when shopping for parts. Some conversion stuff is just flat out expensive, but I can weld, and fabricate. Don't be fooled though. Wrenching is definitely a perishable skill. I was constantly amazed at the screw ups I would perpetrate that wouldn't have happened when I was doing this crap for money.

Advance Adapters, and Novak Jeep Adapters was a huge time saver, because they make many XJ/LS1 specific adaters, and parts. Very good quality, too.

I had to rebuild the 4L60E tranny with a shortened output shaft from Advance Adapters, who also made the adapter for the NV231J transfer case to bolt it on the back of the GM transmission. While I had the tranny apart, I rebuilt it with all new clutches, and threw in an RV shift kit.

After rebuilding the tranny & attaching the transfer case, I set that mess aside, and started on the fun stuff. Wiring. Yeah. Now some folks despise wiring, but I actually enjoy mentally intensive labor like that, because I'm..well, an idiot.

The GM PCM was sent to be reflashed for a 91 octane timing advance, and to switch off unnecessary bullsh... like down stream O2 sensors, and alarm systems & whatnot. Wiring up the GM PCM required taking the ChryCorp PCM, carefully removing it, and setting it on fire...not really. got $60 bucks outta that thing on fleabay. The Jeep PCM controlled the gauge cluster, so that was going to be an issue. The Corvette PCM, really only needed to run the engine, so I had to build relay banks for A/C request, and to turn on the gauge cluster with the ignition. this took forever. It was now about July 2014.



My wiring underwent numerous changes after these pics, because I was less than happy with the results. I'd still classify the almost finished job as adequate, but not pretty. My excuse is, I'm old, blind, my butt hurts, I want my mommy, and it's a Jeep, not a show car.

It was about July of 2014, I'd gone as far as possible on the wiring, without having the engine in place, so I bolted the tranny to it, installed the Novak engine mounts, and installed, pulled, installed, pulled, & installed the assembly in the Cherokee. Progress. There was a lot of trial fitting, header welding, thinking, header welding, redesigning of the headers, wiring, cussing, and buying headers. Man, those freakin headers were a pain. I've made plenty of headers in the past, but I think I've lost my header fabbing mojo with this project.

After finally getting the wiring most of the way finished, buying some aftermarket headers, it was time to get the cooling system ironed out. The LS1 5.7 liter V8 is a much more modern engine than the Jeep 4.0 I 6. It's much more efficient in the area of cooling, but still needs a serious radiator. The all aluminum unit I got for it is huge, It would cool the space shuttle. Finding some radiator hoses was a huge pain,. I went to parts stores, and searched thru the inventory for days, but finally got the Radiator installed, and buttoned up, with all new hose, and fans. Had to use a Ford Taurus 2 speed fan, and modified the shroud to fit. Pop rivets, and aluminum sheet filled the bill for that.

It was about this point I had some health issues, and knocked off for a while, but got back on it about October of last year or so.

My cooling system was installed, engine and tranny in, and I needed to work on the gauge cluster, which had to be fabricated, The Jeep cluster was run by the Jeep PCM, and wasn't compatible with any aftermarket senders, or the GM PCM. I ordered all new Autometer performance gauges, stripped the Jeep cluster from the dash, & cut a piece1/16 inch aluminum sheet metal to fit where the OE cluster was. I then had a local machinist cut the holes for My new gauges, & I wired them up. It wasn't quite that simple, but not reall difficult. Just time consuming. Couple of weeks spent on that.

 

  Fun to watch.  Fun to read.  I've always liked Cherokees.  Can't wait for first loud pedal report. 

  Fun to watch.  Fun to read.  I've always liked Cherokees.  Can't wait for first loud pedal report. 

Doing a little work on it today, & a customer coming to the house for A/C work, but I'll post more tonight.

  

I'm interested in the outcome, this is good stuff jamiemac.   

After working on the gauge cluster, and various odds and ends, I saw winter approaching, and I battened down the hatches, and put away the welders, & tools till spring. I got started again in early march. I'm at the mercy of the weather, but it gave me all winter to research, plan, and make drawings....haha! I didn't do any of that crap! I'm disorganized as a crazy person. I tend to keep plans, and wiring diagrams in my head. My tools are flung everywhere. My shop looks like an apocalyptic nightmare of epic proportions.

I did get started in March though. It was time to build the exhaust system. I did have a plan for the exhaust. I wanted an X-pipe about where the transmission crossmember was at. I wanted 2 1/2 inch mandrel bent tubing. I have some exhaust expertise. I did exhaust fabrication for quite a few years. The mantra at that time was, "get it done, and get it out." I don't think exhaust systems are pretty. I don't like big chrome pipes sticking out the back end, like some version of redneck heaven. I would just as soon not know the exhaust system is even there.

I found the largest stainless muffler I could fit under the Jeep. It's made by Magnaflow. They have quality welded seam muffles. This particular muffler is their X series, dual in, dual out, and an X inside the chamber. About 24 inches long, and it must weigh 30 pounds. I still have the black pinky nail to prove it. I also got one of Magnaflow's very nice, stamped, and welded, stainless X-Pipes. Very compact piece, with 2 1/2 ID inlets and outlets. There's also a plan for stainless flex joints as far forward as will fit in the system, to allow for engine movement.

I used band style clamps at many of the joints, to allow for easy takedown of the exhaust, because I anticipate having to make some drivetrain changes, I. E. grenading the CryCorp differential at some point.

The front pipes were an interesting mix of stainless, and mild steel, because I couldn't find good quality header flanges in the proper shape, made from stainless. I needed at least 3/8 of and inch, because 1/4 inch flanges tend to bend under stress.

Here are some pics of the exhaust during fabrication, and after completion.

I welded an O2 sensor bung to each front pipe. I used mandrel bent tubing from various manufacturers. Aluminized tubing in 16 gauge is pretty good quality form all of the well known speed shops.


A little anti seize on the O2 threads.


The stainless flex joint added to the frt pipes. If You have headers, these things will keep them from cracking after they get some age on them.



The exhaust back to the muffler. Excuse the terrible pics. I was usually pretty tired by the time I took pics at the end of each day.

A shot of the front left, crossover pipe. Not much room under a Cherokee. Both exhaust pipes have to run down the passenger side. That's why I'm using a dual in, dual out muffler.


Flange at the left front header.


I've been welding about 30 years, but I taught myself to TIG for the project. My eyesight is resulting in adequate welds, but I prefer to MIG, because I can weld by sound with the MIG.


The tailpipes are tucked up where they can't be seen, and won't get torn off on the trails in the backcountry.


The X-Pipe undergoing fabrication.


A hunk of wood is a nice spacer, to locate everything till weld time.

By around my 50th, in April, by which I was hoping to be finished (happy birthday to me) LOL, I started getting a little more excited about the first fire-up of the LS1 engine. These engines are rated at 355 HP stock, although a lot of the Corvettes they dynoed are pulling about 320 HP at the wheels, which leads me to believe they have considerably more than 355 HP. My PCM is custom tuned for a 8* timing advance at 2000 RPM, and a tad richer fuel curve. My homemade intake system is pretty efficient, with no restrictions under 3 1/2 inches. The exhaust system is fairly well designed, and as close to equal length as can be in a Cherokee. The Sanderson headers have much better flow characteristics than the stock Corvette manifolds. I'm hopeful for over 400 HP, being as most there is a consensus this engine is about 380 stock.

I wrapped up the final wiring. Ran the starter wires, fuel pump wires, and went to the Shell station to get some gas. I had a new Aeromotive 340LPH fuel pump, and didn't want to accidentally energize it dry, so I left it unplugged until I had fuel in the tank. The fuel system I built for this thing is epic. I spent a lot of time making it robust, and reliable. I'll go into the build of that a little later.

The first fire up of a project like this is always great. The sound of this video is distorted I think because my fancy waterproof phone has a crappy microphone. This engine sounds sweet.

https://youtu.be/RiIfG2Cvym4

 

Backing up a little bit, and laying out the fuel system I built for the Cherokee, AKA Jeepzilla. I knew I needed a robust fuel system, although the stock MOPAR fuel pump has enough output to run an LS1. I wanted something that would be able to deal with any upgrades I might do the the engine in the future. I disassembled the Jeep's fuel pump module and used a fuel pressure regulator eliminator, machined out of aluminum by Novak. This does away with the in tank regulator, so You can run a GM style return line back from the FPR. I then used a stock Corvette fuel filter, which has the regulator built in. They are cheap, and they work. The return line goes from the filter, back to the tank, then the feed line goes the rest of the way up to the fuel rail. Had to use AN fittings by Russell, and Earls, to adapt to the springlock style GM fittings. It worked great. These Russell fitting are the shiznit. http://www.summitracing.com/parts/rus-644123

I used Earls super stock hose, which is a push lock style hose, and doesn't require any clamps. It's compatible with today's crappy gas, unlike traditional braided steel hose, which seeps fumes, and will make Your garage stink. The AN-6 hose ends feed plenty of fuel to the injectors, and can carry enough for any mods made in the future.

Here's some pix.

First thing I did was drop the fuel tank. You can see there was still plenty of Utah crud on the fuel module. Had to clean that off, take out the assembly, and wash the tank inside and out with Dawn dishwashing liquid. I got that thing super clean.


You can see here. the Jeep's OE fuel pressure regulator. They are factory set at 49 pounds, which would run the LS1, but they are designed to run about 60 pounds of pressure. The regulator dumps the excess fuel right back into the module.



Here's what the module looks like without that regulator in place. You can see, there needs to be something there, to bridge the gap in the system, so to speak.


This is after the aluminum FPR eliminator was installed, along with a return line, back to the module.

Plumbing the fuel system took a little research. I wanted to run the stock, nylon style fuel line, seen on GM and ChryCorp cars, but it turns out a kit to assemble that stuff costs more than buying braded AN hose. I didn't want to run braided hose either, because it's notoriously leaky, and tends to produce fumes. Earls has this new stuff called Superstock hose, which is a synthetic rubber hose, with a very tough nylon liner, and it just pushes together for a tight seal. It's pressure rated to 250lbs, so it can handle most fuel system duties, and is great for tranny coolers too. Also, it's important to note, when eliminating the charcoal canister from a fuel system, You have to cap off the vent hose at the fuel tank, and get a vented fuel cap, or Your rig just won't run.

I started with the Corvette filter/regulator, and a separate filter to catch the small stuff.


Then I ran the Superstock hose, up to the fuel rail. It's a simple layout. I did cover the hose in the engine bay with some heat reflective insulation, to prevent fuel heat soak, which is common to Cherokee's because of the tight engine quarters.
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At this point, My old keister has been working on the Jeep since march of last year. I'm tired, but that's normal. It's looking like what I envisioned now. She runs & drives. there were a few hiccups to iron out. The lighter aluminum engine over the frt axle changed the suspension height dramatically. Death wobble ensued. I had to run down all the worn parts. 150K miles on the chassis. Lots of frt end parts have been replaced, but I couldn't remember what. I found one bad tie rod end. The steering on this thing was transplanted from a V8 ZJ (Grand Cherokee), because they have solid tie rods, instead of tubular. Very stout stuff, & good for up to 35 inch tires.

Replaced the 2 lower control arms with Rubicon Express super flex units. They are tubular, and have the added benefit of curing the rub You get with larger tires. The old control arms are free to a good home. LOL Some new shocks up front, & an adjustable track bar to get the axle centered again. That cured the death wobble, and also cured having extra money in My wallet. Can't complain though. I knew what I was getting into.

Anyways, under the hood, things are shaping up.


She parks nice.


I added some special emblems to the frt fenders to mess with several of My buds that have Corvettes.

Things left to do. Get the A/C going. It's requiring some fabrication. I'm fairly A/C literate, so it's something I'm ironing out at this time.

Once the A/C is plumbed, & then wired in, and wired to the dual speed fan, then tested & proven reliable, I'll tidy up the underhood wiring.

Once I get the backup lights wired into the shifter, I'll start getting My interior reassembled. Right now, I've just got the 2 frt seats in for testing and break in.

My transmission build is proving to be very robust, and she always slightly barks the inside tire in a turn during the 1-2 shift because of the auto locker in the rear diff.

I had to pull the tranny last week, to replace my rear main seal, because of my bad judgement. I've done this crap before, and always replace the rear main on a used engine. Well, I screwed up, and stupid oughta hurt.

I'll post some updates when I get her back in order, and I've also been invited to a local car & aviation show in September, and I'll post peoples thoughts from that event.

Jeepzilla lives.

 Later. 

Jamie

 

Thanks Brudda!