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Saturday, August 25, 2012

suspension brackets and 4 link help v2

So how much is a piece of steel worth? I figure that $140 for these axle brackets / 4 hours (max) of my time = "free parts" basically $35/hr. ( I sure don't make that)
Having acess to a punch and plasma cutter help a lot. On right side of the picture is the frame coil bucket, on left side is suspension link / coil spring pad.
The savings are going for mucho sized bolts/ nylocks.  The big holes are 1" dia (12.49 per bolt and 8.23 per nylock) and the small holes are 9/16" all grade 8. sorry- mistyped original bolt price.
About $100 for grade 8 nuts, bolts, and washers.

 
9-17 ...and voila- the right side parts assembled and welded on the frame!  The brake line (hole to the right of the bracket) had a mounting bracket that  had to be chopped off and ground flat to mount this.
 

I'm hoping tomorrow to get the rear brakes bled - finally- and take the jeep around the block to see how the new rear gears feel. THEN I can park it backwards in the garage and start taking off the front axle and start installing all this stuff.
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Heres the basics for a four link design (still have to cut some parts for
the brackets, then I can start lopping off leaf springs)
http://www.therangerstation.com/Magazine/winter2007/4_link_tech.htm
I've read this 6 times and find something new on each reading. 
I used the 4 link calculator  (with update )at the bottom of the page
After punching in some factual and some close guesstimate measurements the suspension
 anti squat is at 95%  (read it- you'll understand).  If its possible to build the suspension like that- it'll work.

Here's what antisquat all comes down to: (big thanks for whoever made this)
The theoretical apex of the suspension links (the point under the block on above picture) determine whether your vehicle will squat or lift up when taking off depending on what side of the vehicles center of gravity its on.  Also how high it is. ( according to the article between 50 to 80% of the CG.)
This helps determines traction too. 
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With a little more accurate measurements the program came up with a 96% anti squat, but the apex is 90% of the CG and about at the rear tires. 
The lower link is in front of the xfer case and the upper is in front of the body support on the side of the frame.  may have to do some tweaking to adjust this...
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9-16-12

 
Clean da frame to prep for welding

 
About at the front floorboards the frame rail goes from 2" wide to about 3".
crash protection??

inside of the passenger frame rail.  only half had to be cleaned because
the inside of the bracket comes up about an inch. (2.54 cm)

 
The outside plate and underframe plate were already welded together in a "t" formation. 
I bolted the big heim in place to align the holes of the inner (left with clamp on it)
 and outer holes.  This is the drivers side- note that 1/2" by 1" had to come off
the top of the inside plate to miss the transmission shifter linkage mount.
 Heim is 1.25" x 1" with 3/4" misalignment spacers.
Also had to loosen the exhaust and remove xfer skid plate for clearance.

The mini lincoln welder holds stuff in place until the old clarke welder hits it tomorrow.
 
There comes a time that the reality of how major an undertaking it is to do this- mine was welding the second bracket at arms length over the exhaust, around the transmission linkage, with my head in front of the engine oil pan just so I could see to weld.  Hope its worth it.
    

Sunday, August 12, 2012

transplant 1

We got home late and since this is the first time in 2 weeks that I get to sleep in tomorrow, I replaced the rear axle.  Somehow I managed to weld the spring perches on in the right place.   It went pretty smoothly, just need to make axle housing brake lines.  It doesn't seem that wide - until the tires went on.  Shiny "new" scout up, dirty old jeep axle lower.

The rear tires (upper near fan) used to stick out the same as the fronts (lower). Roughly 4" more on each side.   There's going to be some fender trimming in the future, and probably some fender flares.

Wednesday, August 8, 2012

coil springs methinks & front end parts

Moog cc875 variable springs made in USA!!! Woot!
5.3" outer dia , 17" unloaded height, 12" loaded height
spring load 680# (around there) 136 in/lb rate (per specs)
I balanced my healthy 215lb. self on one of these and it compressed about an inch.
I figured the leaf springs had to come off anyway just to move them 1.5" to match the axle so why not coils?


These are variable rate (meaning that they start easy to compress then become harder the more they are compressed ) and designed for a ford windstar which happens to be 3400#.
The commando started off life with a 258 at 3020# (the chevy 350 is the same weight)
 at a 60% front and 40% rear weight distribution, I'm figuring about 1800#
on the front end, minus a 350# ish axle, and 200# of tires of unsprung weight = 
 roughly 1200# and both coils are 1360#  (680*2=1360#)
Thus, if I misjudged the weight of the jeep (it could never happen) or a winch was added,
 there's enough overage. 
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8-19-12      I've got the brackets laid out on some 1/4" plate- just need to punch holes and cut them out.  In the meantime- I got overly serious and ordered some front end parts


Got a mix of dom bushings from barnes 4wd (hefty , no zerk options, but 1/2 to 5/8 of the price of some other places) 3" wide , can be chopped shorter if needed , 2" od.1.5 id dom, 1" od x 9/16 id inner sleeve.
The heims are roughstuff 1.25 x1" bore for the main lower link and 7/8 x 3/4 for the upper link.