ghetdjc320

I should have seen this coming. Been chasing down a water leak in the drivers side floorboard for some time now. I had patched in some new metal back when the build was first underway. Near the end of the build, I installed Notch flares which, aside from looking great as an end product, are utter junk for fitment. Part of the install process involves the typical cut and fold of the pinch seam in the wheel wells. Well, as you fold that seem over, you start to slightly open up the two pieces of metal which are spot welded. As I lived in a monsoon climate, water of course worked its way down into those seems that opened up in the fold. This is the result:

Thats not a bad price for a short throw. However, Id be inclined to make one myself. We have a how to somewhere in the DIY section.

Pleased to report that this system is working great now. Just need to source a switched power supply on the board and finish refurbing the radio. The sound quality is superb in both the tuner and Bluetooth sources and there is now zero tuner bleedthrough as I created a digital audio relay system with Bluetooth priority. And the DSP is a tuning dream with endless routing configurations and functionality. I’ll use right angle 3.5mm trs plugs going forward for better clearance. Will also play around with installing a nice amp board at some point. Here is how it laid it out for this demo radio:

Same here. Took me forever to source one as they are scarce now. Then was a giant pains to get it here. But it’s one nice unit to have when it’s all said and done. Plus 88k original miles is nice

There was For the XJ, but this isn’t the police package. This is a somewhat rare UK spec version. The XJ police package speedo was blue/white and looked like the gauge font from the renix era to a degree.

I’m building a very custom setup. Look at my build thread “Project Tomahawk” in epic tech and my post in the diy section “what CC knows about stock Jeep radios” for full details

The new DSP and bluetooth module has been programmed. These things are too cool in what they can do. With the Analog Devices DSP chip, you can create endless automatic signal routing pathways, EQs, ducking settings and so much more. So I wrote the program to do the following: Receive the analog stereo AM/FM signal and pass it through unless there is bluetooth signal present. If bluetooth signal is present (which is an I2S signal for a clean digital pathway and astounding audio quality) the am/fm is digitally muted from the system. The sensitivity for the ducker. is -80db (line level signal) and the dwell time is 5 seconds. I will adjust further if needed. Now we have a digital "relay" that wholly eliminates any tuner bleed-through without disabling anything on the original radio. Then I added a multi band eq system in the mix and will use it to tune the Comanche cab to perfection with my new audio setup. Really neat to inject this modern tech into these old radios and provide so much functionality along with sound quality that would rival most all aftermarket units. And just for kicks, I renamed the Bluetooth friendly name to "Tomahawk" At some point I may also install a nice mosfet amp board in one of these. That would eliminate the need for a separate amp in many installations. I can fit about 400w of class D amp into these units with the tape mechanism removed. With the right combo, I think I could setup a radio that would handle a perfect Comanche 2.1 audio system with the two main door speakers and a sub, all powered through what looks like a factory radio. It would likely have a little cooling fan on it and would have a connector for an 8awg power wire. Fun stuff

These are all over on eBay. You just send them the info and they make you new labels.

Price drop to $350 shipped.

Original b pillar speaker brackets with kicker KS 4x6 speakers installed. $80-shipped

Is it closed all the way?

I often see the grand Cherokee fan clutch swap using a Hayden unit from Napa. I ran that and a 7 blade oe fan and shroud. Very good airflow with that combo. If you have a thicker radiator core though, there can be clearance issues.

I’m assuming you’re using a usb thumb drive? You would need some way to control your media. Typically that’s a smartphone or iPod style device with either a Bluetooth or headphone output. If your music is stored on a drive, you’ll need a way to access the file index and control playback. Although not impossible, it would take a substantial amount of work to build one that does that.

Little teaser for my personal radio build

Technically you could also use a red light filter behind the lcd if you wanted to. That wouldn’t be a bulb filter though. It would be a red semi-transparent plastic filter material.

It took several times of flushing the core to get it clean. Lots of silt and crap stuck on the corners that would come loose. Multiple vinegar flushes worked though eventually. I had crystal clear water after a couple of flushes and then had completely chocolate brown silty water after doing the vinegar flush the next day. Radiator is the same story

Nope, it’s just on the bulb itself. You’d need a color filter for a t1 bulb. Or you could run an led

Try back flushing the heater core by itself. The small passages tend to be the first trap of loose scale and rust from the block. Vinegar works well. You can use the heater hoses connected and let it soak the core for a day then back flush multiple times. You can flush the block separately as well without the radiator

Excellent info. I'm going to compile all these suggestions together into the first thread at some point for quick reference. Id also like to discuss cooling system upgrades that don’t work or don’t work well. What tops my list is still high flow water pumps (unless you increase radiator capacity), thin multicore radiators, and triple e fans (with some exceptions)

Looking good! I’m in the middle of some interior work as well. Btw, @Dzimm makes some console replacement latches if you need them. Upgraded design over stock

So one last note on the signal flow I sure found interesting and this will probably be my final tech entry on these radios. In typical 80’s fashion, there is a lot of circuit back and forth reminiscent of the main wiring harness on the XJ/MJ. Here is a bit of signal flow logic that should prove extremely helpful for future mods: The tape input comes to the preamp board first for attentuation by two potentiometers (one for left and one for right channels) before leaving the preamp board and returning to the main board via the 7 pin connector between the preamp and main board. The main board is the one that selects the tape input or tuner input and typically mutes the other inputs automatically. Until the exact mechanism of switching can be determined along with some type of system hack, there is no point in trying to use the tape input as a selectable source. This may change if I get some spare time someday to create a work around. The main board then send the main L and R audio channels for the radio or casette over two pins that end up connecting to TP471 and TP371 which are where everyone inserts their aux input mod. The signal then goes to the treble tone control, the bass tone control then the volume control. At this point, the line level signal then exits the preamp over the 3 pin jacketed wire to the main board amp section. This is where it gets interesting. Contrary to popular opinion, the amplifier does not have 4 discreet channels, it is a 2 Chanel amplifier only. The amplified two channels now go to the power board where the main relay, main connector and other items are sitting vertically on their own board near the rear. From that board, there is a 6 pin connector that goes back up to the preamp near the volume control. Two of those 6 pins carry, you guessed it, the amplified L and R positive signals. Those two amplified channels then get fed to the balance and fader control which account for the remaining 4 pins on that ribbon connector: RR, FR, FL, RL. These go directly to the main connector speaker outputs. So that pretty much sums it up. With that info, you can mod away to your hearts content. There are so many different options here. It would be relatively simple to convert the internal amplifier to something more powerful and modern. DSP tuning, aux input, Bluetooth input, anything you can imagine is possible. And a note on the bulbs, there are two behind the display (pictured below) and 3 on neo-wedge bases for the front panel illumination. There is another that ilumanetes the tape door. They are all T1 bulbs. The 7219 bulb from VCC (available at Mouser) is a great quality replacement. If you’re changing them all, you’ll need 6 bulb. But I’d grab an extra one or two in case you break or misplace one as they are tiny. Swapping out the bulbs behind the display is a bit tedious but well worth it. Just don’t burn the ribbon cable with your soldering iron or that’s pretty much the end of your radio u less you are a micro-soldering master I also removed a good LCD display from the front panel as a spare.

Overall dimensions are 9w 8h and 6.25d giving .17 airspace with 1/2 birch. Driver displacement of .02 give us a final of .15 and right in the money. Added 40% polyfill to dampen the response a bit. Some update pics of the finished product:

Added the renix temp sensor issue to the list. I’ve been curious about the ported HO mod. I’ve heard two lines of thought on this, one is that the restriction assists in cooling by slowing the coolant flow a bit out of the block to aid in heat transfer. The other is that it’s for thermostat orientation as you mentioned. I know when I swapped to a high flow pump and the high flow housing with a still stock size radiator, I felt the water was moving to fast to effectively transfer the heat.

Very good info. I’ll add this to the list above under “Solutions that work” or something to that effect. I don’t run a mech fan at the moment but can definitely attest to how well they work. When it comes to cleaning/flushing, do either of you use any chemicals?

Agreed. A lot of LS swaps I see don’t properly address the fuel pump. They just think that if it can hit X psi at idle than it’s good to go. They don’t seem to understand fuel demands under load. Interestingly, on my YJ stroker I built back in 2016, I installed a Holley terminator tbi setup. It was definitely running rich. The interesting side effect is that I could not get my engine up to operating temp quickly. I had very little heat in the winter and always ran cool. Never went above thermostat temp and was very slow to even get to that point. On the other hand, a performance built 4.0 I had in my first MJ had lean running condition and every so called “upgrade” cooling component in the book did nothing to fix the issue. I ended up needing to wire in a fixed resistor into my CTS circuit to help the engine think it needed a richer mixture. After that, problem solved! Oddly enough, the hotter an engine gets, the leaner the ecu seems to adjust the fuel trim