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Component speaker deal for your dash - NalinMFGJK Vent Covers - NalinMFGTJ 5.25" Speaker Adapters - NalinMFG

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Unread 12-11-2012, 09:02 PM   #1
comptiger5000
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My 5.9 ZJ Build Thread

There's still a lot to do, and it'll be getting a major suspension revamp when summer hits (10" travel shortbody Bilstein 7100s, stiffer springs, bigger front sway bar, quick discos, possible rear sway bar delete, better track bars and Iron Man control arms with heims at the frame end). I've got a front skid on it now, and still need to add at least a gas tank skid, plus I've gotta install the set of front tow hooks I've got sitting around for it.

For now though, she's got stock front springs, upcountry rears, MX6 shocks, and some engine / trans mods and an exhaust. For accessories, there's a Cobra 148GTL CB, a 1500W power inverter, electronic hand throttle (uses the cruise control servo), manual e-fan switches, manual TC lock switch and probably a few things I'm forgetting. It's also got some seriously high powered lighting (e-codes with 100/55 bulbs, 85W IPF 840 fogs, 100W IPF 968 and some cheapo 100W pencil beam driving lights, both triggered with the 100W high beams).

As of today, she's got 144k miles on her, and runs like a champ.

I'll add to this thread when I start working on further mods, or as any of you have questions for me.

Here are some pics as she sits:





And a video of it running on the street:



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Unread 12-11-2012, 09:39 PM   #2
McCloudsZJ
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Very nice Jeep. Forgive my ignorance, but what's the purpose of the electronic hand throttle on a Jeep like that? I've known people who had welders on board, so they used old bicycle parts to open the throttle to the the RPMS up and run their welders...
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March 2014 GCOTM. 1998 Deep Slate 5.9
On the Jeep:Hot intake, 52mm TB, Summit 8mm wires, catch can, 703s, insulated fuel rails, indexed Champions, Bilstein 4600s, Eibach lowering springs, Moog SS, Ironman mounts, Lotek 2GP, lots of gauges, sparkly paint.
In the garage: M1 4bbl
In the works: Addco/Hellwig sway bars, nitrous, full polly bushings, full exhaust, data logging, billet UD pulleys
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Unread 12-11-2012, 09:45 PM   #3
comptiger5000
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It's for high idle for any time I have to leave it running (running an engine at idle for long periods isn't good for it). It's also good if I need to get the alternator output up when running big stuff off the inverter. I pretty much wired it out of boredom one day, as it's pretty easy to do.

It can be built with an on/off switch, a momentary on-off-on toggle, a 4 pin relay and a 5 pin relay and a diode to prevent the 4 pin relay from being triggered by the computer powering up the cruise for normal use. I don't have a wiring diagram for it, but here's the control scheme for the cruise servo when used this way:

System ON: +12V to Blue/Green, Ground to Green/Red

Throttle UP: Momentary ground to Tan/Red

Throttle DOWN: Momentarily remove ground from Green/Red
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Unread 12-11-2012, 09:50 PM   #4
McCloudsZJ
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Gotcha. That's really neat and pretty simple. Thanks!
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March 2014 GCOTM. 1998 Deep Slate 5.9
On the Jeep:Hot intake, 52mm TB, Summit 8mm wires, catch can, 703s, insulated fuel rails, indexed Champions, Bilstein 4600s, Eibach lowering springs, Moog SS, Ironman mounts, Lotek 2GP, lots of gauges, sparkly paint.
In the garage: M1 4bbl
In the works: Addco/Hellwig sway bars, nitrous, full polly bushings, full exhaust, data logging, billet UD pulleys
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Unread 12-11-2012, 09:58 PM   #5
comptiger5000
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As best I can describe, turning the on/off switch on feeds +12V to the blue/green wire of the servo, and to the 4 pin relay that grounds the green/red through the always-on terminal of the 5 pin relay. The 5 pin relay also receives +12V from the on/off switch. There is a diode in the feed from the switch to the blue/green to ensure that power can't flow back to the relays when the cruise is powered by the PCM.

Hitting the throttle switch to up simply supplies ground to the tan/red wire. Hitting the switch to down supplies ground to the 5 pin relay, causing it to remove the ground from the green/red.

It's extremely sensitive at low rpm with the engine out of gear, as the PCM throws the IAC open when you crack the throttle open a tiny bit, so it'll jump right from idle to about 1400 rpm with no control below that (unless you unplug the IAC, then you have more finite control). I'm still working on a solution to make the IAC not open up when throttle is applied, as this gets annoying in normal driving (can cause a jumpy off-idle response at times, particularly when the engine is cold.
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Unread 12-11-2012, 10:03 PM   #6
McCloudsZJ
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I'm reading other posts from people who've done similar set ups. With the way you have it set up, can you set idle lower than what it should be? Other than idling high for higher output from the alternator, a lot of people seem to run these run their engines at ~300 rpm and take advantage of engine braking on steep descents.
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March 2014 GCOTM. 1998 Deep Slate 5.9
On the Jeep:Hot intake, 52mm TB, Summit 8mm wires, catch can, 703s, insulated fuel rails, indexed Champions, Bilstein 4600s, Eibach lowering springs, Moog SS, Ironman mounts, Lotek 2GP, lots of gauges, sparkly paint.
In the garage: M1 4bbl
In the works: Addco/Hellwig sway bars, nitrous, full polly bushings, full exhaust, data logging, billet UD pulleys
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Unread 12-11-2012, 11:21 PM   #7
comptiger5000
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No, you can't idle down with my setup. It doesn't control the IAC, just the cruise servo, so it's controlling the throttle plates the same way the gas pedal does. At minimum throttle, you'll just be at a normal idle, same as if the system is off.
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Unread 03-11-2013, 11:31 AM   #8
comptiger5000
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After 3 months of no updates, these will be arriving this Friday, and hopefully going on this weekend:
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Unread 03-11-2013, 11:42 AM   #9
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Thorleys?
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Unread 03-11-2013, 11:57 AM   #10
comptiger5000
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Yep. Got a set brand new for $650 shipped (and they're ceramic coated!).
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Unread 03-11-2013, 12:30 PM   #11
squashman702
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Nice man should be a decent bump in power. Are you running your Y pipe or the DT one?
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Unread 03-11-2013, 12:31 PM   #12
comptiger5000
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I'm going to use the DT y-pipe with a new flange adapter behind it (the included one necks the 3" flange down to 2.5" to mate with the stock cat). Mine would need major re-working to work with the headers and probably wouldn't be any better.
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Unread 03-11-2013, 01:43 PM   #13
squashman702
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I thought the DT Y pipe was 3" all the way back? The Mopar headers I sold about a year ago had a 3" outlet.
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Unread 03-11-2013, 03:13 PM   #14
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The DT y-pipe is 3" at the output flange, but the piece they include that gets attached to the cat and bolts up to the other side of the flange necks it down to 2.5". By replacing that piece (sold on Summit as a header reducer), it stays 3" all the way through.
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Unread 03-31-2013, 04:34 PM   #15
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The headers are on and I've fixed all the leaks now. Here's some video (more to come soon).

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