$2010 Race Jeep Cherokee Build

Congrats to Jeff, Dave and the rest of the crew!

I have finally got around to catching up on some of my backlog of reading and was very pleased to see you all get some much deserved recognition. I knew it would be a real quick beast once you eventually got it running...

Trapsp33d wrote: I have so many questions like your power steering did your PS Pump beg for mercy? mine did when I was autoxing I had to go throgh 3 or 4 PS pumps before I got a 99 one and it has held up trough some torture but I would add a cooler or something because evenually without it it will blow and the track official hate PS fluid

hey, glad you liked it! i've really fallen in love with the thing, more than i expected to actually. and its a hoot to drive at local events.

a while back i had the idea of taking our heater fan and making a bracket to mount it to the pulley end of the PS pump so that you could tweak the speed and keep pressure constant without overrunning it, and overheating it, which seems to be a problem in some applications, as even offroading with huge tires they work OK for a long time as rpms are still fairly low. we ran out of time and the stock PS system wasnt complaining too badly so that whole idea got shelved, but i've got a few ideas still i need to mull around. the easiest method might be to find a similar pulley that's larger diameter (if one exists, or cut/weld one up) to underdrive the pump.

so it sounds like you've been autocrossing yours already. what group have you found to run with? what's your suspension/tire setup?

While looking into installing MegaSquirt on another Jeep 4.0L I forgot which vehicle I got the 6 vane trigger wheel from. After doing some research and pulling a bunch of distributors off the shelf at AutoZone I noticed most 80-90’s Ford 6 cylinder distributors have a 6 vane wheel but one of the vanes is a different size. The only one I found that was evenly spaced came from an 1983-1986 Ford 300ci straight 6 but it can't be removed. I found 2 evenly spaced wheels but still have no idea what they came from.This is what we used in the Turbo Jeep Cherokee.

Also there is rumor that the factory Jeep crank trigger wheel will work with MS3 and its included in the current Alpha code but it still needs some testing. . Figured I’d update the tread incase anyone else came across it and needed this info.

Good to know :)

So I wanted to update the build with our latest work:

When we built the rear leaf packs for the $2010 Challenge we took almost two entire stock leaf packs and combined them into one rusty and very stiff pack. One of the packs came off an old XJ that had seen many winters up here so there was a thick coating of rust on each leaf. This resulted in a leaf pack that wouldn't move much. Once we started pitching the XJ-R into corners we realized it was lifting the inside rear tire right off the ground. This combined with a weak LSD resulted in loss of time out of each corner.

At the Challenge Alan McCrispin suggested we rebuild the packs so that they can move freely and not bind. We listened.

Cleaning up old leaf springs:

Before and after

Repacking:

Greased and reassembled:

Custom Andy Nelson leaf spring plate / shock mount:

Wrapped to keep the grease in and dirt out (yes, in duct tape…you have a better idea?!)

We also took the time to rebuild the limited slip in the Ford 8.8 since we were one wheel peeling on the unknown junk yard axle. We restacked the friction packs for more bite and shimmed it as tight as possible while still being able to install the Z-spring. It was a little tight but we got it. Here is a DIY:

Step 1:

Step 2:

Step 3:

Okay not really but since we didn't get many shots of the LSD rebuild this is as good as it is going to get.

Back out on the AutoX course:

Results:

Much better spring movement throughout the entire travel. The XJ-R felt much more planted in the corners and, now that the limited slip actually works, we were able to power out of the corners. The Jeep is dancing between cones with vigor!

Lube and or wrapping leaf springs was common back in ancient times. My Dad taught me to spray the springs with Mystery Oil at every lube job.

I wonder if you could stretch an intertube over the springs to help with keep the grease in.

iceracer wrote: Lube and or wrapping leaf springs was common back in ancient times. My Dad taught me to spray the springs with Mystery Oil at every lube job.

We actually got the idea from the original AC Cobra. Dave re-wrapped a few in his days of Cobra restoration. The wax tape used on the Cobra is very expensive though. We are still looking for a better solution but duct tape works for now.

http://www.plastidip.com/home_solutions/Plasti_Dip

remains flexible, stretchy and will not become brittle or crack in extreme weather conditions; -30°F to 200°F.

Packed with 150% Awesomeness!!

In reply to jrw1621:

Ha, we actually have duct tape in a can left over from the turbo install but i don't think it will work the same as above.

I do like the intertube idea.

CGLockRacer wrote: I wonder if you could stretch an intertube over the springs to help with keep the grease in.

genius!!! Butyl rubber is very resistant to drying/aging.

4cylndrfury wrote:

CGLockRacer wrote: I wonder if you could stretch an intertube over the springs to help with keep the grease in.

genius!!! Butyl rubber is very resistant to drying/aging.

Are we discussing an "inner tube" or something I'm not familiar with?

Since I had a few extra Jeep fuel pressure regulators I decided to mess with a few of them to see if I could increase fuel pressure. I first cut one open to see if there was an easy way to make it adjustable. I was thinking about drilling a hole and threading a bolt in to increase spring pressure but that wasn't going to be as easy as I hoped.

Next idea was to just crush the regulator. This was something I wanted to try at the challenge but ran out of time.

On the first try I found it crushed much easier then I though it would. I installed it in my jeep and fuel pressure hit over 80 psi. I grabbed another and crushed it it a little less to ended up with 50 psi which should work out fine with the new injectors.

Also we just started a facebook page:

Jeep-Cherokee-XJ-R

miatame wrote:

4cylndrfury wrote:

CGLockRacer wrote: I wonder if you could stretch an intertube over the springs to help with keep the grease in.

genius!!! Butyl rubber is very resistant to drying/aging.

Are we discussing an "inner tube" or something I'm not familiar with?

yep, a bicycle inner tube is made from butyl rubber...a halogenated form of butyl rubber is a major component in car tires today - its the part that makes a tire hold air (the layer closest to the rim). The rest of the tire is hard and resists wear. Butyl rubber is pretty amazing stuff...

This thread is so full of bad ass win.

I really wish this forum could email me when there are new posts :)

So I'm somewhat concerned about the 4.0L sitting for the winter. Someone (you know who you are) left the XJ-R running without the fan running and we popped the radiator (very old).

So the system doesn't hold fluid but I think there is some left in the engine but I can't get coolant to stay in. I need a quick fix since it is dark and cold now. I just don't want the block to freeze.

miatame wrote: I really wish this forum could email me when there are new posts :)

It can, you add the topic to your watchlist by clicking the heart button below the reply box at the bottom. Then go to edit your profile and check the box that says send watchlist notifications.

EvanB wrote:

miatame wrote: I really wish this forum could email me when there are new posts :)

It can, you add the topic to your watchlist by clicking the heart button below the reply box at the bottom. Then go to edit your profile and check the box that says send watchlist notifications.

Wow you're the best! Thanks

I try to make at least a small number of my posts helpful.

Are you bringing the truck back to the challenge for $2012?

aussiesmg wrote: Are you bringing the truck back to the challenge for $2012?

The goal was/is to have the suspension ironed out, the turbo on and running full time, and pretty it up.

The first task is done...

Yes, we are bringing the XJ-R back in 2012, I hope.

Incredible. Subscribed.

This vehicle inspired me to borrow some 225/50-15 Hoosiers and slap them on some used BRAID wheels for an autocross last summer. Alas the event was cancelled and we sold the wheels but I did get to drive it round a parking lot a few times. The small tires and all that torque were a blast but with stock suspension, even though the tires lowered it quite a bit, it felt a bit scary.

Good job lads.

Bumping this so it can get moved to the build thread section and so Jeff might post some updates for $2012.