High travel, high clearance & high octane, a streetable adventure LJ story

Phil Younger said:
How is the filler cap or tank vented to atmosphere to allow for fuel consumption?
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The filler cap is sealed. The tank is vented via the 2 roll over valves and then looped around the roll cage in a particular way so that it's safe in a rollover. I've never noticed a pressure difference when removing the filler cap so I think that's working fine for fuel consumption. Between that vent and having a large diameter 1-3/4 to 2-1/4" filler neck tube I was betting on it being enough but obviously it wasn't.

I'm not super worried about moisture because the tank is otherwise sealed off (aside from the single 3/8" atmosphere vent hose) so there isn't air traveling through the tank while sitting, I buy ethanol free premium when I can, and unless I plan to burn the tank within a week I add marine stabil. An aluminum tank isn't great with moisture either and I do need to make sure it doesn't condense with temperature changes.
 
someguysjeep said:
nice find.
i might go for that 1. the flange would allow it to mount to an aluminum plate but could also allow the top to be fit tight and removable (no matter where the hole ends up), with just the 6 face screws. make a gasket and the top will seal well. and vent tube to boot , that's the ticket.
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I'm also thinking that this cap is the one. Better than the one I had been using before (sucks how much they cost though). It's also available in black but I fear that it'll get scratched quickly with tree branches.

Cheaper and faster with 2 day delivery from France but may not be virus free 🤣: https://en.oreca-store.com/newton-a...-5-mm-retention-cable-and-lead-free-flap.html

CarBuilder.com/us/ also has good inventory of the Newton caps but apparently they don't use lead free restrictors over there.
 
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toximus said:
I'm not super worried about moisture because the tank is otherwise sealed off (aside from the single 3/8" atmosphere vent hose) so there isn't air traveling through the tank while sitting, I buy ethanol free premium when I can, and unless I plan to burn the tank within a week I add marine stabil. An aluminum tank isn't great with moisture either and I do need to make sure it doesn't condense with temperature changes.
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You are overthinking the moisture gain even with E10 where you live because we are not on the coasts or deep humid south. Even my guys racing on E85 only bothered to start their carb'ed engines every 2 weeks to keep the snot out (in the carb there is huge air presence). (not so with methanol---horribly hydroscopic they dump at the end of the race night). Where you live if you are operating it weekly even with an open atmosphere vent you still do not need the marine stabil (and never use the non-marine version at all). And for reference for anyone who is listening-——-never ever use the yellow bottle version of HEET -especially in any carb'ed engine unless you love doing carb repairs.
One last thing and i will stop messing up your really truly great thread so you can go on with it-— consider some sort of pressure/vacuum vent on that fuel cell open atmosphere vent-- gasoline begins to boil at as low as 90 deg (winter grade) and just a bit higher for summer grade. Forcing some small pressure rise does three things: 1) prevents as much as 10% of the cell volume loss from boiling per month 2) retains all light ends in the gas for better quality, 3) greatly reduces daytime to night air volume change which introduces cool moist night time air (particularly spring/fall or coastal areas).

Keep up the awesome work- great thread!
 
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I was caught off guard today. Saw this pic and thought it was your Jeep.
956F2669-FD23-480A-8E44-4A326BEA33F4.jpeg
 
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I'm putting aside the remote filler neck while parts come in to work on shock tuning.

With the tune Fox included with the coilovers and the compression adjusters turned all the way down my Jeep feels like the suspension hits a bump, the shocks get packed up, and they aren't traveling back down by the time the Jeep drives off the back side of the bump. Simply put it physically hurts to ride in. I discussed how it felt with my shock tuner, discussed specs of my build, and sent a couple of pictures so he could get an idea of the build he'd be tuning for. I also asked if he'd possibly let me do the work myself to minimize downtime and to my surprise he sent me the shims to do the work myself! I promised not to share the secret sauce so unlike 99.9% of my build I'm not allowed to discuss the specifics of what shims I'm using. Sorry! We are allowed to discuss theory however so I promise it'll be interesting!

To get a better idea of how a good tune should function, my tuner recommended watching videos of trophy trucks. Some trucks such as Andy McMillin's the tires are constantly moving around, others such as Robby Gordon's the tires stay more static in relation to the body. A good tune maintains contact with the ground which allows for traction and prevents pulling as contact is lost.

On a basic level how these shocks work is there is oil in the shock body that the shock shaft travels through. On the end of the shock shaft there is a piston with shims on it. The shims control how the piston and shaft move through the oil. When the shock is compressed the shaft travels into the body of the shock and since the oil can't be compressed there is a remote reservoir with compressed nitrogen inside. A piston inside of the reservoir separates the oil from the nitrogen.

In a Jeep tune putting a flutter stack into the shims is nice to have. This allows the piston in the shock to have a small break away pressure when hitting small road events but another stack of shims prevent the flutter from cracking open too wide. I think of it as a door stop allowing a door to easily be opened a small amount quickly but requires a lot more force to open the door all the way.

My front shocks are getting a tried and true tune that may require slight changes later, but the rear is more experimental which will probably require a few alterations over time.

I removed the coilovers from my Jeep and prepped my workbench for a weekend of shock tuning! By having a vice on each end of the workbench I'll be able to hold the shock body in one and hold the shaft in the other.

20200326_shock-tuning-prep.jpg
 
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To prevent contamination inside the shock I wiped the bodies down with WD-40.

20200327_cleaned-coilover.jpg


These small shims effect how the shock handles by covering ports in the piston.

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I charged them all up to 200 psi and while I was at it I reduced the pressure on the air bumps significantly.

After that first shock took me just over an hour, the others I had retuned in about 30 minutes each. What took the longest is mounting them back on the Jeep and dialing in preload again.

A couple of special tools that came in handy are having a lossless airchuck, and a multifunctional shock wrench.
 
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got my front axle under the rig yesterday. all the linkage is connected and i was even able to refit the stock drive shaft.
i'll be cycling it today, but can already tell the shaft is gonna contact at least 1 of the tranny lines.

i notice you went to a smaller diameter shaft but could not pinpoint the reason.
i found the info on pg30 of your clearances. and i have clearance at the pan. it's up higher where the line enters/exits the housing. did you have any issues here?
 
someguysjeep said:
got my front axle under the rig yesterday. all the linkage is connected and i was even able to refit the stock drive shaft.
i'll be cycling it today, but can already tell the shaft is gonna contact at least 1 of the tranny lines.

i notice you went to a smaller diameter shaft but could not pinpoint the reason.
i found the info on pg30 of your clearances. and i have clearance at the pan. it's up higher where the line enters/exits the housing. did you have any issues here?
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I'm not sure where you're talking. Can you take a picture?
 
it's the feed or return for the tranny cooler line. it's got a huge sweep on the bend, that's right in my up travel.
i'm gonna have to bend or replace that end tighter to the case.

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thanks guys. i guess i jumped the gun some b4 i tried.
i was able to get more bend on it and now the DS sneaks by with 1/8" clearance stuffed level.
i need to drop the pass side and see how the TB controls it, while the passenger side moves up n down. but it should swing down and away.

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and that's at 1/2" above needed travel.
 
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toximus said:
I ordered a blank Saginaw flat pitman arm from PartsMike:

http://www.partsmike.com/index.php/products/pm536fpa-pitman-arm-flat-undrilled-525-7

Also sold by PSC as PA700: https://www.summitracing.com/parts/pfn-pa700

I then drilled and reamed it to 4.929" center to center to match my mock up. To remind you from one of my earlier posts, DO NOT use my measurements as any sort of guide for yours. Make mockups and figure out the length you need, there's no way to short cut this frustrating process and still get perfect results. For reaming, you really need a drill press in order to get it straight, so I'd put that fully on the shopping list before starting this project if you don't have one already — it'll also make drilling all of the many holes so much easier. I'm using the XKUT #5952 (1-1/2" per foot) reamer I mentioned a few posts ago to match the taper of the TREs.

The first mark on the arm is at 4.9", second is the 4.929" I went with:

View attachment 98700

View attachment 98701

I kept checking the depth of the taper by tightening down the TRE. I wanted just enough so that a cotter pin will slide through the castle and no more.

View attachment 98702

Somehow mine ended up perfectly clocked on the sector shaft (what are the chances?) but It's highly possible that the pitman arm wasn't going to be clocked on the splines the same as my mockup. If that was the case, I can either bend the arm or reposition the TRE on the upper steering arm slightly to correct. A custom waterjet arm with press fit splines is also be an option if those routes don't pan out. I had bought the shop press and oxy acetylene setup just for this moment! I'll have to come up with an excuse to get my flame on another time.

The arm is thicker than my mockup arm was so the castle nut on the top needed additional clearance from the frame. I'll clean up my notch and be plating over it at a later step.

View attachment 98703
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i got my throw all jacked up. the wheel's hitting an inch b4 the gear limits. i have the same pitman. the original (mistake) 6" throw hole might leave enough meat for me to still use it. but i'm gonna be down low on that flat similar to where yours ended up.............and that might well have me diggin a hole into that steering gear mount as well. i hope i got enough flat to get my spot.

i'm finding myself using your thread for references almost daily. glad you documented stuff and had pics to go with. once again nice job.

i found a similar pic of that tranny line next to your drive shaft and yours is bent way tighter than mine i got some room now but not much (1/8-3/16").
 
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I've been wondering what backspace you chose for your wheels, and what went into the decision making process for selecting that backspace.
 
someguysjeep said:
i got my throw all jacked up. the wheel's hitting an inch b4 the gear limits. i have the same pitman. the original (mistake) 6" throw hole might leave enough meat for me to still use it. but i'm gonna be down low on that flat similar to where yours ended up.............and that might well have me diggin a hole into that steering gear mount as well. i hope i got enough flat to get my spot.

i'm finding myself using your thread for references almost daily. glad you documented stuff and had pics to go with. once again nice job.

i found a similar pic of that tranny line next to your drive shaft and yours is bent way tighter than mine i got some room now but not much (1/8-3/16").
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Nothing wrong with redoing it to get it right. After you get over the fear of notching the steering gear mount it's not bad, I think it took me an hour of actual labor to do.

Thanks for the kind words. It was my hope when I started this build thread that I would be able to share good building theory and techniques. Thankfully nearly all of advice I've received I've been able to pass along freely here.
 
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LowRange said:
I've been wondering what backspace you chose for your wheels, and what went into the decision making process for selecting that backspace.
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I went with 3.5-3.75" of backspacing to have the best scrub radius and because any more backspacing would place the 17" rims into the lower steering arm of the knuckle. Because of this, track width should be set by a narrower/wider axle and not by adjusting backspacing.
 
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Work's been crazy since COVID so I haven't had much time for my Jeep.

After tuning the shocks I took her for a test drive. It rides great, but I want to get the spare tire back in and get the Jeep to it's normal weight before analyzing how it rides and adjusting. So we'll come back to the shocks again soon!



The final piece to the puzzle before working on minor finishing touches is to get the remote filler neck working. Thankfully I don't look like a weirdo wearing disposable gloves at the pump anymore as many are joining me this past week in wearing gloves in solidarity to my fillerneck but I still do get looks getting paper towels ready in expectation of the overflow. I added the filler vent but it still barfs up gas when filling quickly.

20200405_ORB-to-AN.jpg


20200405_filler-breather.jpg
 
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