Jeep Speed Goat TJ, the anti-build thread

The 21 Road test run was mostly a success, nothing broke and I got a pretty good feel for the changes. - Rock Junction & 21 Road





I didn't run the trail to the end because I noticed that the passenger rear tire was lightly rubbing on the strut. Not wanting to damage it, I decided to call it good enough at the Alcove and head back to the trailer. The trail gets rougher just past the Alcove.

I will say that I'm very happy with the outcome after all that work.

The ORI Struts work amazing, they're super stable and the valving/rebound feels great.

The PSC 2.75" DE cylinder is incredible, the TJ steers amazingly well with the front locked and bound up.

The ride height seemed decent for 21 Road, which usually was quite rough for my old TJ.

The Nitto Trail Grapplers just plain WORK for a DOT tire, I was at 10 PSI and could have been lower.... even with water in the wash and wet tires, they stuck and held my line very well.

Adding the sheetmetal over the transmission cooler fan really reduced noise and heat in the cabin, it was loud before!


I do have some things to work on... the rear axle is off center just a hair, which is why the strut cleared on the drivers side but rubs on the passenger side. I'm going to add 1/2" spacers (hate spacers) for now, but soon will move the lower shock mounts in about 1/2-3/4".

My steering reservoir has leaked from the first time I took it out, I replaced some hoses and thought I found the culprit... but apparently not. After a search and some reading, it sounds like a thicker o-ring on the cap may take care of the issue.

The exhaust is way too loud on the trail, going to try some different mufflers.... possibly add race cats to help quiet it down?

For years my exhaust was a high flow spun magnaflow cat into an aero turbine muffler. soooo loud that you couldn't hear your own thoughts and no chance of hearing a spotter. i got creative and added a carven TR "muffler"/resonator after the muffler and it has made things soooo much better. probably would have helped just to add more tubing past the muffler too rather than just a turn down. but i'm happy with the additional muffling

RockChucker said:

For years my exhaust was a high flow spun magnaflow cat into an aero turbine muffler. soooo loud that you couldn't hear your own thoughts and no chance of hearing a spotter. i got creative and added a carven TR "muffler"/resonator after the muffler and it has made things soooo much better. probably would have helped just to add more tubing past the muffler too rather than just a turn down. but i'm happy with the additional muffling

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I'm running dual exhaust, 2.5" pipe into a 3" Dynomax resonator and a 3" Magnaflow Performance muffler, both straight thru, with a 2.5" turndown tip. I hoped the resonator would tone it down, as I knew the Performance Magnaflow would be loud. I think the 3" size and straight thru setup is most of the issue.



I don't have a ton of room (as you well know) so I'm trying to stick with 4-5" round mufflers.

I have two 18" Flowmaster Super HP-2 Mufflers coming, I'll check out the resonator you added and see if I can fit it as well.

I just want it quiet enough I can have a normal volume conversation while it's running... and don't want it to sound like glasspacks. I'm picky about exhaust sound... lol.

Totally get it. That is basically what I used to have as well, basically a 45 turn down after the muffler, but I have 3" single. I THINK it helped slightly that I angled it about 45 degrees so it wasn't pointed straight at the ground. I think having more tube after the muffler helps tone things down too by taking out some of the rasp and bite. Exhaust on a small Jeep/buggy is hard.

Since we're talking exhaust, I didn't mention this in the build when it happened... too much going on. I took @RockChucker suggestion on the Armor Exhaust Heat Shield, wrapping the pipes from the collector past the t-case. I added another layer of heat protection, with Thermo-Tec Acoustical and Heat Control Mats on the floor under drivers and passengers areas. Both additions seem to have made a huge difference in heat control, it was a warm day on the trail on Sunday and neither of us noticed any heat radiating from the exhaust thru the floor.





And since it was brought up earlier, the TeraFlex Olympus Beadlocks took a beating on 21 Road and survived quite well! Some scratches on the rim lock itself, but that's it. The plastic hub caps survived 21 Road!

While I was on 21 Road, I noticed I had problems shifting the transmission while twisted up. I crawled under the TJ and found this... apparently the trans shift linkage was binding on the driveshaft when the driver front was at full droop! Took a grinder to the excess threads and that should be enough.

My narrowed axle moved the diff in just enough to create this problem.

Well, the Speed Goat is plated... with a black Colorado vanity plate! SPDGOAT 😍

UNSTUCK said:

I need 50 of them to put in our fleet of trucks.

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I can supply you with 50 of these stickers.........

Spent some time working on the cooling system and exhaust, trying to get it to sound more reasonable. The engine got really warm during the Pritchett & Moab Rim trip last weekend and that was quite concerning. The engine was running around 220-230*'s on Pritchett with 90* ambient temps.... LS engines usually run pretty cool, so something isn't quite right. I maxed out at 240*'s on Moab Rim, which is way too hot.

I swapped out the 185* thermostat for a cooler 165* unit and added a bottle of WaterWetter from Red line. WaterWetter is awesome, it helps break the surface tension in coolant, allowing for better heat transfer. It's usually good for 5-10*'s of cooling, in my experience.

I've also ordered an aluminum shroud for the radiator and upgraded the fan to a 16" Spal 2000 CFM unit (most 16" fans are 1000 CFM), should be here sometime this week. We'll see how they fit.... it's already tight without the shroud. Those parts should help keep it cool in 4 low when there's no real air flow.



With the TJ idling in the shop, it used to run run at 210*'s.... now it stays around 190*'s. Same for driving it around the neighborhood, just cruising around I didn't see over 195*. Once the new fan and shroud are on, it shouldn't have an issue with getting hot on the trail.


With the exhaust, I ended up running dual 18" x 2.5" Flowmaster HP2's and a short 10" exhaust tip with turn downs. The HP2's aren't straight thru, they have a mesh screen inside which is cone shaped. I had the Craven resonators, but the body was big enough I couldn't really fit them and when I tried to put them on after the Flowmasters, they sounded horrible. Just a bad combo, the Craven's were wide open... no tailpipe, so that didn't help. I feel like they'd be better ahead of the muffler, or with a decent bit of tailpipe, but I just don't have the room for that option.




With just the HP2's the tone is quite a bit more reasonable.... the harshness isn't there, especially at idle. Don't get me wrong, it's still loud... but at least I can have a conversation in the cabin of the TJ without shouting. I think the sound is decent, these aren't a chambered muffler like the traditional Flowmaster, so the sound is different... it's a bit 'poppy' but it's better than it was. I'm done with trying to make it any quieter.

I have a digital sensor and an analog sensor, one on each head and they both registered a consistent 210 temps on my 5.3L running a mechanical fan. So let us know if you get any difference in temps doing what youre doing.

85CUCVKRAWLER said:

I have a digital sensor and an analog sensor, one on each head and they both registered a consistent 210 temps on my 5.3L running a mechanical fan. So let us know if you get any difference in temps doing what youre doing.

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I will for sure, driving around the neighborhood isn't a proper test... need to be in low range, running the RPM's up and getting minimal air flow. Hopefully I can get the shroud and Spal fan on before next weekend and hit the trail again for a proper test.

You may want to adjust your fan turn on temp to be much closer to your thermostats open temp so they can work together. If it wasn’t adjusted from the stock setting it’s likely turning on so late it can’t catch up.

UNSTUCK said:

You may want to adjust your fan turn on temp to be much closer to your thermostats open temp so they can work together. If it wasn’t adjusted from the stock setting it’s likely turning on so late it can’t catch up.

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I'm going to, just forgot to mention it. It seems to turn on at 185*'s now, which is stock setting.

Need to buy a credit and play with HP Tuners and the LS3.

The Battleborn Gatekeeper beadlocks are fine wheels, but they don't hold a candle to the quality and look of the TeraFlex Olympus beadlocks. 😍

I swapped the 39" BFG Krawlers over to the new Olympus wheels... and even show mounted the BFG's.

It'll be nice to have some killer wheels with a set of sticky 39" Red Label Krawlers for the really challenging trails.

Continued work on the cooling, I have the HP Tuners interface and the software, so I purchased two credits in order to change the LS3's tune & fan temps. The software has some limitations and isn't the most user friendly for someone that doesn't have a ton of tuning experience, but I did lower the temp. The spread and low temp start is limited down low where the fan turns on. I set the fan to run at 65% under the lowest setting at 192.2* and then 100% under 195.8* and up.

After uploading the changes, I started the TJ up and let it idle and get up to temp. It looks like the fan now turns on at just over 180*'s on the gauge and it seems to do better managing the cooling while idling, as the low temp thermostat opens and closes. With ambient temps around 90*'s it stayed between 180*'s and 190*'s.

I took it for a drive around the neighborhood at speeds under 40 MPH (decent load, not a ton of air speed) and it seemed to stay around 195-210*'s.

I still haven't added the shroud or Spal electric fan, so that's the next step. Still, I'd like to get it out on the trail while its still warm out and see if it runs any cooler in low range.

Been putting the TJ thru it's paces in the last month, wheelin HARD trails 4 weekends in a row! Coyote Canyon twice, Hanging Tree Trail and 21 Road.... and it's holding up well! Some minor issues along the way, but they're to be expected. Really happy with the DOT Nittos, how stable the ORI's feel, the height and wheelbase, etc. It's all been working out great! The engine does need some tuning work, but for now it works.



I did manage to mangle the front license plate though... I knew it wouldn't last long up there and with my driving!

Removed the windshield frame for a couple upcoming trips, it'll just get in the way for what I have planned...might as well get it out of harms way!

I need to do that. Nice option to have.

Happy 1 Year Anniversary, Speed Goat! ❤️

Winter is officially here and it's time to make a plan for upgrades over the next few months! I have more work than I had planned, the last trip to Sand Hollow was pretty brutal for the TJ and has created more work than I had anticipated.

• One of the issues was that the entire dash has come loose when things got rowdy. Looks like it pops into place and the clips that secure it have worn out. I need to decide if I'm going to keep the stock TJ dash or upgrade to something more simple & lighter. GenRight makes a aluminum flat plate TJ dash kit, but at $1000 it's a hard pill to swallow. - https://genright.com/shop-by-vehicle/jeep-tj-97-06/jeep-tj-lj-laser-cut-aluminum-dash/ I think I could build something way crappier for 3/4 the cost...
• The old school rocker switches are outdated, the momentary switch for the starter actually sticks 'on' and if you're not aware, you can f**K up the starter in short order. I really don't like the old switchs and would like to upgrade the ignition, starter, lights & other switches. I really like the Switch Pros SP9100, but it's spendy at $660 - https://store.switchpros.com/sp9100-switch-panel-power-system/ Aux Beam has something similar that's only $269, which is a huge difference in price, just don't know about the quality difference. - https://auxbeam.com/products/ar-800-rgb-switch-panel-with-app-toggle-momentary-pulsed-mode-supported
• I still need to clean up the rear winch plate & mount (cutting & grinding), would like to add a aluminum panel for the very back, want to enclose the bottom and add a proper mount for a cooler.
• Need to figure out which rod end is clunking and get it replaced, that's a new development.
• Want to swap out the 15 gallon fuel cell with external pump to the 18 gallon Goat Built fuel cell with the factory GM internal fuel pump and sending unit. I'll have to rebuild the mounts, so that'll complicate the swap.
• Need to repair the hood from the rollover, the driver front corner broke off and that's where the latch mounts, so it's going to be tricky.
• Need to keep working on the cooling issue for when it gets hot, adding the fan shroud and new higher CFM fan.
• Need to decide if it's worth adding the MotoBuilt front frame-half kit. I could have used it in Sand Hollow, my approach angle with the stock frame became an issue a couple times. But it's a TON of work, redoing shock mounts, engine mounts, etc.