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Joel's multipurpose XJ build (rocks/boulevard)

I know. I've been meaning to get Brian the measurements requested on the gas tank skid too, just haven't had any time. I'd say I'm slacking but the reality is that I just resigned from my job, I'm moving my family across LA to a home we have yet to find, and I start a new job next Thursday. This is all notably harder because I have a two year old and a 2 month old at home. The Jeep's going to have to wait for a bit, as is the Ford 8.8 IRS rear going into my RX7 (Ford rear in a chevy powered mazda, that's cool right?)

The bonus is that the new job comes with a bump in pay and I turn 33 next week. I'm thinking seriously about some RCV axle shafts. Seems easier than worrying about spares and/or pulling out my existing u-joints to do the full circ clip mod. Given I'm only on 32s with 4.10 gears I think my ring and pinion would be OK. It's just so much simpler than jumping up to a D60 and I'd rather drive this thing that work on it indefinitely.

Thoughts?

I have some pretty trick interior storage I'm proud of but otherwise this is getting relatively current in terms of progress. Oh and my trans decided to burp fluid again the other day so I need to ensure the trans is venting properly.
 
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Do some temperature logging on the left and right side, front and rear of the transmission to see if the exhaust is actually putting heat into the transmission or if it is simply an airflow issue.
 
By the way, I drove this without the tail section one time on the freeway. Remind me never to run a turn down. The droning on the freeway was un-livable. So far as I can tell, dumping the exhaust under the car just reflects the sound waves off the ground straight back into the bottom of the vehicle.

If anyone is looking for a cheap exhaust I was momentarily temped by the low buck route from the DynoMax catback
https://www.google.com/search?q=xj+exhaust+dynomax&sourceid=ie7&rls=com.microsoft:en-US:IE-SearchBox&ie=&oe=#hl=en&rls=com.microsoft:en-US%3AIE-SearchBox&tbm=shop&sclient=psy-ab&q=xj+cat+back+dynomax&oq=xj+cat+back+dynomax&aq=f&aqi=&aql=&gs_l=serp.3...7862l8876l2l9094l8l8l0l0l0l5l234l1449l0j6j2l8l0.frgbld.&psj=1&bav=on.2,or.r_gc.r_pw.r_qf.,cf.osb&fp=25828f9a7ae54771&biw=952&bih=763

That said, I just couldn’t bring myself to throw those u-clamps back on the Jeep. I think I spent 3x as much in materials for my version, but it’s exactly how I wanted it so I’ll deal.

Underbody armor is next (this is the part where I kind of went off the deep end).

Funny you should say that, I ran the exact same setup on my last XJ and goodness that got old very quickly with a turndown. My brother also has the same setup, but with a tailpipe and is much more tolerable and sounds much better.

Nice exhaust work btw and great attention to detail (your gonna cry when you hear that thin metal scraping and crunching the first time), I love V bands also, I used to work for Wolfe Race Craft where we milled them out for turbo and exhaust setups in house, I tried to use them as much as possible while I could get them cheap.
 
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love this build... i believe a skid similar to yours is in my near future... do you have any measurements from your gas tank skid? if you dont mind me asking


Four plates make up the body of the skid. From the front (closest to the diff).

Vertical plate: 5.25 x 31.5
Horizontal plate: 11.625 x 31.5
Angled plate #1: 9.0 x 31.5
Angled plate #2: 3.5 x 31.5

Sides:
Total length 22.25
Starting closest to the diff (0 = vertical plate)
At 0 it is 8.5 tall
At 11.5 it's still 8.5 tall (horizontal plate length)
At 19.625 it's 4.5 tall at the next apex
At 22.5 it's 2.0 tall with the end squared off.

Beyond that you just need all the flanges. Still cut that out of cardboard and you'll be 75% of the way to a template.
 
Joel, Thanks!!!
 
Still need to get around to posting up a few more things. Life's been pretty crazy with the move and all. Did manage to sneak in a pretty cool family camping trip to Jawbone Canyon (just a bit outside Mojave, CA). My 2.5 year old daughter loves wheeling.

8DSC_0124Custom.JPG


Night wheeling is awesome. Definitely need to track down a lighted whip. That thing was a hoot to follow around...

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8DSC_0136Custom.JPG


-Joel
 
Night wheeling is awesome. Definitely need to track down a lighted whip. That thing was a hoot to follow around...

They didn't have one at the Jawbone store?

Good work.
 
To the above, I've never actually stopped at the Jawbone store to know what they have. Pretty much always went straight in to meet whoever we were meeting.


In the meantime, I've started another big round of work on the rx7 (hoping for north of 550 rwhp now). That means the Jeep's mostly been cruising around serving it's duty as the fall back vehicle with a little bit of wheeling here and there.

About a month back I was in Wildomar, CA checking that out and at the end of the day I found I was stuck in 4wd for quite a while. Finally got out by rolling backwards and forwards a few times and I thought it was behaving normally. Then this last weekend took a buddy and my two year old up to the top of Main Divide (also a SoCal spot).

MainDivideCustom.jpg


It's pretty light so I did almost everything in 2WD. That said, when I did go into 4 low at one point (just messing around) there was a pretty terrible clicking noise from the front diff. Kind of a catch and release sound, but not distinct single pop I can point to as part failing followed by clicking. I'm guessing it actually happened last time out and I'm only now seeing the results since it still drives normally in 2wd.

Anyone blown up a spartan locker? That's my guess. I need to tear into it and just see what I find, but with the RX7 down for a while I'm loathe to do it immediately so I thought I'd post up to see if anyone can point to suspects. At the same time, if it's possible I have a chunk of something floating around the front end I don't want to screw something up badly by having lodge in between ring and pinion.
 
Anyone blown up a spartan locker? That's my guess. I need to tear into it and just see what I find, but with the RX7 down for a while I'm loathe to do it immediately so I thought I'd post up to see if anyone can point to suspects. At the same time, if it's possible I have a chunk of something floating around the front end I don't want to screw something up badly by having lodge in between ring and pinion.
perhaps you have bent/broken pins.
 
Hello,
You have a very good XJ.

And I would to know if you had a drawing of your tank armor???

Thank you and good ride

Thanks it's been fun. I didn't make a drawing for the aluminum gas tank armor as this went directly from cardboard mockup to one-off production. I did post quite a few dimensions in the middle of the thread though.

Give these a look and let me know if anything needs clarifying.

http://www.naxja.org/forum/showpost.php?p=245637954&postcount=85

-Joel
 
A few pictures of my storage area. Goals:

-Keep the back area organized
-Stash the high reach and other heavy stuff in case of accident
-Add multiple tie down points including extra spots for for child seats
-Maximize storage volume while keeping it low profile (ended up about 6" tall, basically what the high reach needed plus 1/2" extra margin)
-Make something tidy


Result:

7DSC_0886Custom.JPG


7DSC_0887Custom.JPG


7DSC_0888Custom.JPG


-Structure is all 3/4" plywood. Center spar is double thick so each cap has a good landing surface. Hardest part was keeping it all square since the seat back isn't all that straight. One side is actually a 1/4" longer than the other to avoid any gaps.
-It's wrapped in amplifier felt (almost like the factory carpet), need 4 square yards.
-Tie downs are the Chevy pieces from the Tahoe's, Suburban's and even a variety of vans.
-Latches are an over center part from McMaster.
-A single piano hinge was sliced in two on one side of the hinge only to allow the two leaves to move independantly.
-All the day to day crap is on the left (cables, cb, ratchet straps etc).
-All the recovery gear is on the right (tire chocks, tackle, rock straps).
-Need to add so gas springs so these stay open will parked on an uphill but otherwise I'm stoked on it.

Joel
 
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Random CA smog saga for those entertained by such things:




PITA 1) had to pull off the massive skid plate because I’ve replaced my exhaust and you have to be able to read the numbers on the cat. This makes no sense to me since if I didn’t have the skid the cat would be scratched to hell and you wouldn’t be able to read the numbers. Went to three shops and everyone said the same thing. So I cave and pull the skid.

PITA 2) the cat I’m running is a Magnaflow 45036. I carefully bought it because it’s the CA smog legal version of the cat for my car….


Magnaflow45036_CarbEO.jpg


….only it turns out it’s not.

The carb executive order (EO D-193-91) applies for 1996-98 and mines a 99. www.arb.ca.gov/msprog/aftermkt/devices/eo/D-193-91.pdf

This makes no real sense to me because 00-01 had the different cylinder heads (the ones that crack sometimes). Maybe I’m wrong but I thought 99s were identical to 96-98 engine wise. Anyways, we strapped it to the rollers and turns out it’s a moot point because it failed the 15 mph test with high oxides of nitrogen. ~1200 vs. 570 allowed. Probably needed more cat anyways. Everything else looked great on the numbers.

PITA 3) I still had the stock cat so rather than run through the hoops with cat legality some more when I’m now doubting it’s a big enough cat. I bought some extra v-bands and spliced the original cat back into my fancy stainless setup. My welder buddy can’t come down so I spend a chunk practicing doing TIG butt welds on my own. Go easy on me, it's been a decade since I last did this.

TigPractice.jpg


There went a Sunday afternoon I didn’t have to spend on this but whatever. No pic of the finished version but you get the idea. It should be good because it passed last time with the former exhaust.

Nope. Failure #2. NOx dropped down to about 900 but the cat is still not getting it done.

PITA 4) Lots of reading about what causes high NOx. Everyone points to high combustion chamber temps. Inspect it carefully for vaccum leaks (seems good). Run a can of sea-foam through it to remove carbon deposits just in case. Change the oil. Fill it with premium gas. Refresh the K&N filter. Replace spark plugs because they look a little warn. FWIW the plugs do look like they might be little lean…

Plugs.jpg


As such, I replace the 02 sensors because they’re cheaper than I thought and my license plate is about to expire so I’m getting desperate. Wipe the ECU per instructions found online: http://www.quadratec.com/jeep_knowledgebase/article-89.htm and then carry out permutations of the OBD2 “drive cycle” until all the tests check in. It did takes a few cold starts and a mix of careful driving around town and on the freeway, but definitely not the 50 cold starts and 500 miles some folks have claimed.

Oh and I should mention that while I was messing with spark plugs the inner clip on one of the Mopar “Performance” plug wires pulls out. Anyone know if there’s a lifetime warrantee on these things? I jam it in there as hard as I can and pray I’m good. $100 in parts and wrenching annoyances later and I take it back in feeling confident.

Nope. Failure #3. After all my changes NOx is now failing worse than test number 2 and is hovering at about 1100. WTF… I’m losing faith in my garage mechanic abilities.







There’s a saving grace though. Mechanic thinks he hears an exhaust leak. Header looks good so the only likely candidate is the junction between the stock header and where my custom exhaust starts. PITA 5) Pull it apart and check it out. Damn, black marks all the way to the edges of the junction; that’s definitely not right…

Leak.jpg


I go digging for what I can use to seal this up since I need a smog check NOW and I’m short on time to find a new ball gasket. High temp RTV? Nope doesn’t handle enough heat. Wait, at the very bottom of the fluids and sealers box… “muffler mender”. Hmmm, I might be JB welding my exhaust to the header but worst case I can break the junction sand off the crap and redo it later. It’s worth a try.

Mender.jpg


Next day I stop by Autozone on the way to one more smog check to buy some dielectric grease just in case my spark plug wire isn’t happy. Enquire what plug wires go for and if they have them in stock. They do and it’s only $20 so I cave and figure it’s better safe than sorry. Go outside to install them in the parking lot. Don’t know what goes where so I’m going one wire at a time.

PITA 6) I’m going one wire at a time to be sure I don’t have anything mixed up. The two wires that cross each other are a little short but I figure it’s just a crappy design. I’m 4 wires in and realize I only have 1 wire left. Look everywhere to be sure I didn’t drop it. This is a 6 cylinder. The heck? Did someone open and box and pull one out? Take it back inside and claim I’m missing a wire. Nope, that’s the right kit. Anyone see where this is going?

A few minutes later “Oh, you said 4 LITER? I thought you said 4 cylinder. The kit you need is XXXX number. It comes with 7 wires including the lead but it's $30 not $20.” Change all the spark plug wires AGAIN. This is going to be a long lunch hour.

Take it to a new smog shop (better reviews for helpfulness on yelp and one free re-test if needed) and hold my breath….










PRAISE THE LORD, it passed (sent my wife that exact message as a text actually). :eeks1::eeks1::eeks1:

Passed with flying colors no less. NOx around 100 for both speed tests.

So, let that be one more check for y’all. Exhaust leaks can screw with your 02s and/or cats. Original cat was probably fine (albeit now I have the stocker so I don’t have to mess with numbers matching headache). And since just about everything I replaced was probably good at least now I have spares.

I might just have to rethink my plan about dropping the v8 in. That was the type of smog pain I haven’t had in a long long time.

-Joel
 
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Diggin the hell out of this build. The attention to detail and over-engineering is a welcome breath of fresh air. Definitely going to be stealing a few of these ideas.

I grew up in Tustin, right near Nelson Elementary. Lived there until 1998 and moved out to Georgia and now N. Carolina. I'd stab someone right now for a double double.
 
Diggin the hell out of this build. The attention to detail and over-engineering is a welcome breath of fresh air. Definitely going to be stealing a few of these ideas.

I grew up in Tustin, right near Nelson Elementary. Lived there until 1998 and moved out to Georgia and now N. Carolina. I'd stab someone right now for a double double.

Thanks... I feel like I don't know what the hell I'm doing most of the time so I just design things like I would go-fast parts (but with bigger loads expected). I'm one of the three founders/owners of Ronin Speedworks. BTW the school you mentioned is only about a half mile from me. Were you in Tustin Meadows or on the other side of Walnut?

Umm wow.. You've got some skills my friend.. :cool:

Thanks. I have a theory that the challenge of effective wrenching is all about overcoming the headaches that crop up; the bolt you snap and have to dig out etc... This smog thing was more of a month and half migraine, but I was stoked I figured it out. At one point I was so frustrated that I literally wanted to sell my rx7 and buy a classic just so I wouldn't have to deal with it. Even went and checked out a Bugeye Sprite. Unfortunately an 80" wheelbase just sounds twitchy with any real power behind it.

You know you're a car guy when you can stuff your hand into some really awkward position and turn a bolt by hand 5 degrees at a time for 20 minutes to get something out (or back in).
 
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