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

Wow! I was impressed with my 15" BBK, but those brakes are massive!

They are huge. You have to remember when looking at the pictures that they are on a 5x5.5" bolt pattern so the scale is also bigger. Here's some pictures of these same calipers on 5x4.5" with the Super 16 kit:

bbkinstalled.jpg


The calipers compared in size to OEM:

comparecaliper.jpg
 
They are huge. You have to remember when looking at the pictures that they are on a 5x5.5" bolt pattern so the scale is also bigger. Here's some pictures of these same calipers on 5x4.5" with the Super 16 kit:

View attachment 68449

The calipers compared in size to OEM:

View attachment 68450

I wonder if those calipers are the same size as the ones on my 17" big brake kit.

If so, I wear a size 11 shoe, and the caliper is actually longer than my shoe!
 
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Who manufactures the calipers?

One of my main questions when ordering the front axle was if I should go with Currie's or Black Magic Brakes front calipers. They are both very similar on paper and expense. The difference is that BMB's calipers are higher quality US made calipers and you get the black compound pads.
 
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Where the drag link connects up on the steering arm in relation to the pivot point on the knuckle (ie. balljoint) creates a steering ratio with the steering gear. I'm starting with a 1:1 ratio. The pitman arm started at 5.5", so this distance is also going to be 5.5" to make it a 1:1 ratio. I mocked the plate up on cardboard. Eventually this part will be made out of 3/4" plate steel, to make mock ups easier I am using 1/4" plate (although I may end up using thinner 3/16" plate for future renditions since it's faster to work with). On this 1/4" plate mock up I am using a 1" OD 0.25" wall DOM tubing cut to 3/4" length for the tie rod end to seat in to simulate the plate I will later be using. I reamed the tubing out with a 1-1/2" per foot taper (XKUT 5952) to match the taper on the GM tie rod ends.

20181220_mock-up-plate.jpg


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(ignore the extra taper on the underside, I had accidentally started reaming with the bracket upside down...)

Next, I measured the nominal tie rod length to match for the track bar and ended up going 2" longer to go from the inner-C to the frame. The axle side mount is DOM tubing tacked to the passenger's side inner-C as far outboard as I can place it. The frame side is a single shear mock up bracket to allow for easier adjustment — it will later be double shear.

20181222_mock-up-track-bar.jpg


I was able to cycle the axle and get a feel for how it travels. Approximately 5" of up travel is very easy. Beyond that my complications are hitting the frame on the passenger's side, the lower radiator hose with the UCA, and the engine mount with the UCA. Doing steering tests I found that the steering gear has more travel remaining when the steering stops bottom out on the knuckles. I need to adjust the previously mentioned 1:1 ratio by either lengthening the distance on the knuckle side mount or shorten the length on the pitman arm so all of the stops hit at the same point. A lot of small adjustments and tweaks are ahead of me.

20181222_links-hitting-frame.jpg


20181222_linkages-front.jpg


20181222_mockup-links.jpg


20181222_top-view.jpg
 
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I received the replacement skid for the front. Part number 60-9085SP. I have no clue if this is different than 60-9085B or not. But hey, it fits.

To stop the tie rod from binding I drilled out 5/8" grade 8 washers to 3/4" and placed them as spacers under the heims on top of the lower steering arm.

20181224_drill-washer.jpg


20181224_58-washer.jpg


I did check my toe by clamping angle iron to the rotors and it's ever so slightly toe in.

I then played around with moving the linkages:

20181224_working-on-steering.jpg


I'm not really going to explain every little change I'm doing as it's just too specific to the relative placement of linkages. The short of it is that I am making small changes, cycling the steering and axle, and making more small changes. Until it all clears. Lots of small gains to add up to larger gains. If I can think of any more general things to point out while I'm doing it I'll be sure to mention it.

Have a great Christmas!

20181224_christmas-spring.jpg
 
Your track bar looks longer than your drag link to me? Since you are going all the way to the inner C, you consider putting in inside the frame?

Here's mine, ignore the rust. Sat out under a carport for a month. :(
8a7a740ed2cce7de846bb246c9b40547.jpg


Sent from my Pixel 3 XL using Tapatalk
 
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Your track bar looks longer than your drag link to me? Since you are going all the way to the inner C, you consider putting in inside the frame?

Here's mine, ignore the rust. Sat out under a carport for a month. :( View attachment 69143

Sent from my Pixel 3 XL using Tapatalk

The track bar is 2" longer than the drag link. This places it on the driver's side about centered on the width of the frame. I hadn't considered placing the track bar inboard. The track bar and drag link are hitting the frame at the same point so I am indifferent about notching the frame for the track bar also.

Here's an early mock up to show generally where the placement is on the driver's side:

IMG_20181222_161852.jpg
 
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Looks good. Mine are exact same length, but I doubt you'll feel 2 inch difference at all.

Also consider where you are putting the coilover mounts. Going all the way to the C with the trackbar may make it harder, so consider lower c/o mount location before final.
 
Looks good. Mine are exact same length, but I doubt you'll feel 2 inch difference at all.

Also consider where you are putting the coilover mounts. Going all the way to the C with the trackbar may make it harder, so consider lower c/o mount location before final.

I have a few ideas for CO mounts, either off the LCA mounts or on the top of the tube. I stretched the front by 2" and will probably lay the COs back slightly. I am a little concerned with fitting air bumps in. I only have 65WMS to work with so it's CRAMMED. I think I'll still be happy I went with 65" but it sure makes building less forgiving.
 
Yeah. I cut down my axles to 65 from 68 (mistake), then had to go shallower backspace to get the width back. 3.5 instead of 4.5.
82a5df3efd47f89a0ec4bc7be0a556df.jpg
 
Yeah. I cut down my axles to 65 from 68 (mistake), then had to go shallower backspace to get the width back. 3.5 instead of 4.5.

Primarily from a building standpoint, or from a performance standpoint?

My reason for going 65 was for better clearance on our woods trails which is mostly what I will be on. While legal, they're not groomed trails and tend to be more frequented by ATVs and UTVs so they can get narrow tree trunk to tree trunk. In the desert and JV type trails I hope it won't be a huge compromise.
 
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Primarily from a building standpoint, or from a performance standpoint?

My reason for going 65 was for better clearance on our woods trails which is mostly what I will be on. While legal, they're not groomed trails and tend to be more frequented by ATVs and UTVs so they can get narrow tree trunk to tree trunk. In the desert and JV type trails I hope it won't be a huge compromise.

Both. The rear is where the extra width really helps, depending on what you have for shocks.
 
Sometimes I question my luck. As I was setting up the steering stops I noticed that I was getting different results by moving the knuckles by the rotors vs moving with the steering wheel. I narrowed the issue down and found that my steering gear box output shaft (sector shaft) has some slop in the backlash in some positions.

20181227-sector-shaft-backlash.gif


Unfortunately this is going to delay my build since I have the holiday week off to work on it. Thankfully PSC is able to send out a replacement today.
 
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