Yet another post mount lift question

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Cataldo
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Yet another post mount lift question

Post by Cataldo »

Hello Everyone,

Thinking out loud on which way I will go for a lift on my '75 Wagoneer. Hell Creek and Rusty's are so far my most likely choices. The obvious factor is cost, I was thinking of running Rusty's 4" lift with AAL and blocks in the rear, but my springs are flat. I have not talked to Rusty's about building a post mount spring (Im pretty sure they will say no, but it never hurts to ask). Assuming that is not an option, I am contemplating running the AAL and blocks and just trimming the AAL to fit the shorter spring. That got me thinking about trimming the full leak packs to fit the post mount main leaf or figuring out a 76-91 style rear mount in place of my post mount

So:
-74-75 main leaf (With new bushings) and the leafs off of the full leafs from the Rusty's kit
-Trimmed AAL from the Rusty's kit
-New shackle mount for the rear on my '75

What are y'alls thoughts on this?

Thanks
Jay

1975 Jeep Wagoneer: 350 SBC, TH400, Q/T, D44's 3.54:1's. Hell Creek 4" lift with BFG KO2 33x10.5s.

1988 Jeep Wrangler: 305 SBC, TBI, 700r4, NP231c with SYE, 9" w/ Detroit and 4.11:1, 5.25" of lift, 31's. Done up as a Jurassic Park Jeep (Her's)

1973 Chevy Camaro: Vortec 350, 200-4r, GM 8.5 3.23's. 12.4 @ 108mph.

1965 Ford Mustang: Aluminum Headed 347, c4, 3.00:1 gears, High 12's (Her's).



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Cataldo
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Re: Yet another post mount lift question

Post by Cataldo »

Talked to a gent at Rusty's and he basically gave me the same options. They do not make their own springs.

I am thinking of running their full leaf set ups and trimming the back part of the leafs to fit the 74-75 main leaf.

Has anyone done this?
Jay

1975 Jeep Wagoneer: 350 SBC, TH400, Q/T, D44's 3.54:1's. Hell Creek 4" lift with BFG KO2 33x10.5s.

1988 Jeep Wrangler: 305 SBC, TBI, 700r4, NP231c with SYE, 9" w/ Detroit and 4.11:1, 5.25" of lift, 31's. Done up as a Jurassic Park Jeep (Her's)

1973 Chevy Camaro: Vortec 350, 200-4r, GM 8.5 3.23's. 12.4 @ 108mph.

1965 Ford Mustang: Aluminum Headed 347, c4, 3.00:1 gears, High 12's (Her's).



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Tad
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Re: Yet another post mount lift question

Post by Tad »

74-75 rear springs are the same length, width and spring pin offset as the 76-91 rear springs.
The difference is we have those big 1" bushings and the 76 and newer use a 9/16" bushing.

Seems to me it would be simple to just use your existing mainsprings with the 76-91 spring packs.
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Re: Yet another post mount lift question

Post by Cataldo »

Tad,

Huh! that is awesome, I though 74-75 rear springs were shorter, if that is the case then it seems like a great way of doing it. Will just need to source new bushings for the rear leafs then.
Jay

1975 Jeep Wagoneer: 350 SBC, TH400, Q/T, D44's 3.54:1's. Hell Creek 4" lift with BFG KO2 33x10.5s.

1988 Jeep Wrangler: 305 SBC, TBI, 700r4, NP231c with SYE, 9" w/ Detroit and 4.11:1, 5.25" of lift, 31's. Done up as a Jurassic Park Jeep (Her's)

1973 Chevy Camaro: Vortec 350, 200-4r, GM 8.5 3.23's. 12.4 @ 108mph.

1965 Ford Mustang: Aluminum Headed 347, c4, 3.00:1 gears, High 12's (Her's).



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Re: Yet another post mount lift question

Post by Tad »

Nope, I'm wrong.
I was reading the front spring spec's so you would have to cut them down.

Not sure if that would alter the spring rate enough to make a difference.
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Re: Yet another post mount lift question

Post by Cataldo »

Tad, not to doubt you but I found this link from the mother ship http://www.ifsja.org/forums/vb/showthread.php?t=66430 It says that the rear springs on 74-75 is 26" x 26" x 2.5" and 76+ is 26" x 31" x 2.5", which makes them 5" longer all of which is on the rearward end of the springs.
Jay

1975 Jeep Wagoneer: 350 SBC, TH400, Q/T, D44's 3.54:1's. Hell Creek 4" lift with BFG KO2 33x10.5s.

1988 Jeep Wrangler: 305 SBC, TBI, 700r4, NP231c with SYE, 9" w/ Detroit and 4.11:1, 5.25" of lift, 31's. Done up as a Jurassic Park Jeep (Her's)

1973 Chevy Camaro: Vortec 350, 200-4r, GM 8.5 3.23's. 12.4 @ 108mph.

1965 Ford Mustang: Aluminum Headed 347, c4, 3.00:1 gears, High 12's (Her's).



Looking for 1 good factory Kidney Bean Mag in Southern California for use as a matching spare
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Re: Yet another post mount lift question

Post by Cataldo »

Tad wrote:Nope, I'm wrong.
I was reading the front spring spec's so you would have to cut them down.

Not sure if that would alter the spring rate enough to make a difference.
10-4

Yeah that was one of my concerns with nipping the end off the springs. I figure though that I could even run the new main leaf as well if it is too soft, which I do not predict will happen.
Jay

1975 Jeep Wagoneer: 350 SBC, TH400, Q/T, D44's 3.54:1's. Hell Creek 4" lift with BFG KO2 33x10.5s.

1988 Jeep Wrangler: 305 SBC, TBI, 700r4, NP231c with SYE, 9" w/ Detroit and 4.11:1, 5.25" of lift, 31's. Done up as a Jurassic Park Jeep (Her's)

1973 Chevy Camaro: Vortec 350, 200-4r, GM 8.5 3.23's. 12.4 @ 108mph.

1965 Ford Mustang: Aluminum Headed 347, c4, 3.00:1 gears, High 12's (Her's).



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Re: Yet another post mount lift question

Post by Tad »

When my junk was stock a local spring shop found me some 2 1/2" rear lift springs for a Chevy that were 52" long.
They came with 9/16" bushings but the guy was able to find a 7/8" bushing for front post.
(I'll find the part numbers, I run them under a trailer now)

That doesn't totally help since you need a 1" bushing for 74-75.

I also had the same shop source some bushings for my 72 J2000 on Chevy springs those part numbers also.
Not sure if they were 1" or 7/8" but I can look (I still have those main springs too).
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Re: Yet another post mount lift question

Post by Cataldo »

Great, I have yet to look for bushings for the rear leafs and shackles. Looking at the Jeep there is the cheapest option of doing a shackle flip and blocking it the rest of the way, but obviously this is significantly down on the best way list since my springs are original and flat.
Jay

1975 Jeep Wagoneer: 350 SBC, TH400, Q/T, D44's 3.54:1's. Hell Creek 4" lift with BFG KO2 33x10.5s.

1988 Jeep Wrangler: 305 SBC, TBI, 700r4, NP231c with SYE, 9" w/ Detroit and 4.11:1, 5.25" of lift, 31's. Done up as a Jurassic Park Jeep (Her's)

1973 Chevy Camaro: Vortec 350, 200-4r, GM 8.5 3.23's. 12.4 @ 108mph.

1965 Ford Mustang: Aluminum Headed 347, c4, 3.00:1 gears, High 12's (Her's).



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Re: Yet another post mount lift question

Post by Tad »

These are the part numbers from the 2 1/2" lift springs they found me.

Image

These are the bushings they found me for the J2000 springs.

Image

I would have to do some comparing to see if they would fit the Triangle springs.
I'll try to look at both in the morning.

I did have a lengthy conversation with Tom Laher from Hell Creek at the time.
I scrapped the J2000, it was a long time back so I'm not recalling what the conclusion was but they are obviously able to get bushings that fit since they do sell springs that fit our 74-75 model wag/cheros.
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Re: Yet another post mount lift question

Post by Tad »

The shackle flip thing works for post mount rear rigs but it's hit and miss.
If your springs are in good shape it's visibly obvious that it pushes the axle forward and tilts the pinion up.
Ujoints are pretty forgiving with that small an angle change or degree shims can be used.
There's not anything you can do about the axle position change.

It's one of the top reasons I tore all that stuff out and went SOA front with a true shackle flip in back.
It was hard and math intensive but it works and I have never regretted it.
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Re: Yet another post mount lift question

Post by Cataldo »

Great info!

How did those springs ride? And dare I ask flex? Haha
Jay

1975 Jeep Wagoneer: 350 SBC, TH400, Q/T, D44's 3.54:1's. Hell Creek 4" lift with BFG KO2 33x10.5s.

1988 Jeep Wrangler: 305 SBC, TBI, 700r4, NP231c with SYE, 9" w/ Detroit and 4.11:1, 5.25" of lift, 31's. Done up as a Jurassic Park Jeep (Her's)

1973 Chevy Camaro: Vortec 350, 200-4r, GM 8.5 3.23's. 12.4 @ 108mph.

1965 Ford Mustang: Aluminum Headed 347, c4, 3.00:1 gears, High 12's (Her's).



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Re: Yet another post mount lift question

Post by carnuck »

I found some 8" lift '72+ Chevy rear springs that I considered. I have new 3" ones that were bolted in and just sat the past 10 years.
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Re: Yet another post mount lift question

Post by Cataldo »

How well do the chevy rear springs work? Stock works out to 2.5" lift on fsj so a 3" would make for 5.5"?
Jay

1975 Jeep Wagoneer: 350 SBC, TH400, Q/T, D44's 3.54:1's. Hell Creek 4" lift with BFG KO2 33x10.5s.

1988 Jeep Wrangler: 305 SBC, TBI, 700r4, NP231c with SYE, 9" w/ Detroit and 4.11:1, 5.25" of lift, 31's. Done up as a Jurassic Park Jeep (Her's)

1973 Chevy Camaro: Vortec 350, 200-4r, GM 8.5 3.23's. 12.4 @ 108mph.

1965 Ford Mustang: Aluminum Headed 347, c4, 3.00:1 gears, High 12's (Her's).



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Re: Yet another post mount lift question

Post by Tad »

Cataldo wrote:Great info!

How did those springs ride? And dare I ask flex? Haha
They rode like most lift springs, stiffer than stock but not terrible, more truck like than FSJ springs.
I ran them with a 2" block to match the 4" lift up front.
A collection of 1966 to 1986 parts.
Self Inflicted Flesh Wound
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Re: Yet another post mount lift question

Post by Cataldo »

Huh I like that a lot. So in theory 2" lift springs for the early 70s chevy trucks would give 4" of lift?
Jay

1975 Jeep Wagoneer: 350 SBC, TH400, Q/T, D44's 3.54:1's. Hell Creek 4" lift with BFG KO2 33x10.5s.

1988 Jeep Wrangler: 305 SBC, TBI, 700r4, NP231c with SYE, 9" w/ Detroit and 4.11:1, 5.25" of lift, 31's. Done up as a Jurassic Park Jeep (Her's)

1973 Chevy Camaro: Vortec 350, 200-4r, GM 8.5 3.23's. 12.4 @ 108mph.

1965 Ford Mustang: Aluminum Headed 347, c4, 3.00:1 gears, High 12's (Her's).



Looking for 1 good factory Kidney Bean Mag in Southern California for use as a matching spare
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Cataldo
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Re: Yet another post mount lift question

Post by Cataldo »

Humm the problem that comes up with the 2" chevy springs is they are right at the same price as hell creek ($266 a pop) and need bushings to boot. Unless I were to get some old jy chevy springs in good shape and make my own bastard pack for now. Then block the rest of the way. Humm.. decisions decisions
Jay

1975 Jeep Wagoneer: 350 SBC, TH400, Q/T, D44's 3.54:1's. Hell Creek 4" lift with BFG KO2 33x10.5s.

1988 Jeep Wrangler: 305 SBC, TBI, 700r4, NP231c with SYE, 9" w/ Detroit and 4.11:1, 5.25" of lift, 31's. Done up as a Jurassic Park Jeep (Her's)

1973 Chevy Camaro: Vortec 350, 200-4r, GM 8.5 3.23's. 12.4 @ 108mph.

1965 Ford Mustang: Aluminum Headed 347, c4, 3.00:1 gears, High 12's (Her's).



Looking for 1 good factory Kidney Bean Mag in Southern California for use as a matching spare
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