Mr.T

Appreciate that...

Mr.T

Just back from a desert vacation -- Death Valley, and the greater surrounding area. Wheeled with several friends, including some from the East Coast that rented a Jeep from Farabees in DV.

Big Dune is a dune where you can have fun and solitude.

Spent some days there alone, and went with friends some other days. The GY Adventure 285/70-17 tires worked well at ~13 PSI. Having experimented a bit, Lo-Range at >12 MPH with the manual transmission is becoming my default for dunes -- Lo is easier on the clutch when starting uphill (such as when stopping to get out and make sure it's OK to go forward over the top) and >12 MPH seemed to be enough momentum for what we mostly do. Lo-Range also makes engaging the locker(s) possible on the Rubi, but that's been a rare occasion.

I had an opportunity to drive a rental 2017 Jeep with 255/75-17 BFG KM's and an auto transmission. The auto trans was much easier, shifting gears quickly with a manual trans in sand is an art form I've not perfected. Hi-Range worked well with the auto trans, which never overheated. Note that in Hi-Range, disabling the ESP with a 7 second long press is a must! The rental was striped down, no floor mats, no camping gear -- less weight drives better! Some friends had 35" tires and loaded 4-door Jeeps. Everyone's tire sizes were more or less proportional to weight, so there appeared to be little difference in capability on the sand. Something that came up in discussion, and we experimented with, is that it's (almost) impossible to get stuck on level sand with typical weight, tires, and air pressure. And on a hill, one can at least back down. We deliberately didn't air down the rental Jeep, got it stuck, then aired-down to 15 PSI and it drove right out.

It's very cool to find water in the desert, this is a small spring in Cottonwood Canyon.

Below is the spring at Johnson Canyon.

And this is our Jeep on the latter part of the old road through Johnson Canyon.


My wife takes better pics, but getting them from her phone is a pain -- maybe later...

The "Boring Build" is working well. The new Raybestos EHT brake pads feel better (take less pedal pressure) than the original brakes, both cold and hot. This is the second set of GY Adventure 285/70-17 tires. After ~42K there was plenty of tread for summer highway use, but rocks tend to round off the biting edges and the snow/ice traction wasn't there anymore. Just bought some 0w-40 for the engine, and will likely send in a sample for analysis to include in the 5w-40 oil thread. It's also time to change all the rest of the lubricants too, It's been about 65K since the last complete lube change-out.

The wife and I are slowly becoming more and more minimalist (boring). We don't carry a stove, cookware, or anything that requires refrigeration. BTW, Krave Jerky tastes great.

jedg

Very nice!!!

Mr.T

Often this thread is a reference dump for things that may come in handy...

Starter Amps: 230 A [peak hold, begin cranking] and 150 A [during cranking] at 70F - cold 3.8L engine.

Starter voltage drop on #6 ground wire, measured from Batt Neg to Engine Alternator bracket [peak hold]: 0.3 V

Starter + lead is #4 wire.

Had some nice hi-temp #10 fine stranded wire and made another [peak hold] ground voltage drop test with #10 wire added from Batt Neg to engine alternator bracket: 0.2 V using the starter (instead of 0.3 V).

Not a huge difference, but decided to dress it up with plastic split-sleeve and make it look factory -- 33% less voltage drop from junk in the shop. "Peak hold" captured the highest voltage drop and amperage when the starter first engages.





Not having any problems, but this thread https://www.jk-forum.com/forums/modi...4/#post4303947 caught my eye. Semi-retirement is nice, a bit of time to experiment.

Mr.T

An open hood is a universal sign of trouble, and airing up a single vehicle with the hood open tends to cause folks to stop unnecessarily. 'Been meaning to do this for years...

This Deutsch DTP connector is wired back to a fuse connected to Bat+ and the ground stud near the TIPM fusebox. The wire routing was done with the air cleaner housing removed first. When not in use, it's plugged with a connector using dummy (white plastic) pins.


The compressor is connected this pic.


Here's the connector on the compressor. There's also a mating connector attached to the regular Viar battery clamps so they can be used as well.

Mr.T

Originally I used some Anderson Power Pole connectors (that were already on hand) in the above post. Anderson's aren't waterproof, and adding a dab of silicone to the back didn't help much. After a couple of uses it became apparent they were not going to hold up long term, so I installed some Deutsch DTP connectors instead.

The DTP's are waterproof and rated for 25A continuous. The compressor is rated for 30A maximum, but it only draws over 25A at full pressure of 150 PSI, and the highest measured was only ~28A.

The DTP connectors are not that expensive, but the crimper was $45, hopefully it will get used again. There's not a lot of 25A (12 gauge wire) waterproof connectors available, and these look good for all sorts of projects.

Mr.T

I haven't done software engine tuning before. It turns out that it's a lot easier than adjusting carburetors and distributors back in the old days. It's more accurate, has more possible adjustments, and it's fun. Reminds me of my mis-spent youth.

If you'd like to use this tune, you can download it here. Just load your original tune, then use the compare feature in the VCM Editor with this tune. Try what you like and leave the rest... If for some reason the link is dead you can always PM me.

There actually are software methods to get more usable power out of a stock engine such as the 3.8L, like eliminating the delay for PE (Power Enrichment with more spark advance). The stock delay is 6 seconds!

The stock spark timing is a degree or two optimistic about fuel octane, which results in excess KR (Knock Retard) with regular 87 gasoline at higher throttle -- That's fixed. My guess is that typical fuel runs at the low end of the spec, and manufacturer's use fuel at the high end of the spec for a better HP rating while letting the knock sensors take care of the difference.

I made an improvement tuning the speed control loop for idle spark and throttle, especially for letting out the clutch without touching the throttle. For those with a controls background, there's PD on the spark advance and PID on the throttle. There was also some spark knock at higher IAT (intake air temperature) with RPM's below idle speed under load (high MAP) that needed less spark advance too.

After adjusting fuel stoichiometric, VE (Volumetric Efficiency), and the fuel temperature compensation, the fuel trims are are staying much closer to zero.

The scanning software (data logging) records just about any value available at the OBD port, and displays it as a trend chart or even a spreadsheet style for fuel trims and spark advance/retard. The road is your dyno and data logging is your friend.

Going back down memory lane... I still have a HeathKit Exhaust Gas Analyzer that I built back in the 1970's. It ran off 12 volts, but was meant for stationary use like testing the idle mixture. However, with some bailing wire and duct tape (literally) I used it on the road to check the A/F ratio after adjusting carbs. Sometimes the past was better, and sometimes not.

TrailBadger

Guess our 017 Unlimited build would be considered "boring" also as we're doing the RK 1.5 & TJM Gold edition shocks.

Mr.T

I like the length on those shocks, almost exactly the same as what I'm using. Appears to be about max travel before needing other changes.

karls10jk

I'm due for a brake change in the rear so I'd like to get your feedback on these pads after putting some miles on them. I know plenty of people who run to the Hawk pads (myself included) but the immense brake dust and marginally better than stock stopping power has me looking for greener grass. I'm coming from the Wagner OEX pads in the rear, which again, are just ok in my book.


Thank you sir!