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Here's the Descrambler

371K views 1K replies 129 participants last post by  W.R.Buchanan 
#1 · (Edited)
Here's the DeScrambler

Here is a brief overview of what I'm doing. Diesel Powered Jeep Scrambler, built from scratch. How's that for brief?

I could never have found what I wanted in the real world because nobody makes a diesel powered Jeep, it doesn't exist, so I felt I must build it. It's called the DeScrambler because I am descrambling the myth of having a diesel motor in a Jeep which seems to have eluded Jeep's marketing in this country. They offer it in every country except the US. And from what I've gathered it's nothing more than typical political BS keeping them out. Plus that, when they do give us one it won't be built like this . Since I started 7 years ago others have built diesel Jeeps, and from what I've seen here just about everything else too. I think this is the first complete ground up build., and surely will be unique.

I have fabricated the frame from 2X4 x.120 wall tube. A stock Scrambler frame would not carry this drivetrains weight or power. I have overlapped the joints in an unusual manner to gain strength with out adding enormous weight which would rob performance. I am estimating 3500-4000 lbs. complete for this vehicle. 25-30MPG seems entirely realistic and is what I have been shooting for since I first started drawing this project in April of 2001.
Yeah, I know, 7 years!

The suspension is 4 Fiberglass monoleaf springs which have Jonny Joints on each end for articulation. I could have designed any suspension I wanted and was even offered several from manufacturers. I chose the leafs for reliability. They weigh 13 lbs each, and come from Chevy Astro Vans so they are well proven, and as simple as you can get, but with excellent performance characteristics. they don't rust, squeak, or take a set, and will maintain the ride height for life. Spring rate is approx. 350 LB/ inch per spring.

Axles are High Pinion D44 front, 4.10 gears, ARB lock, 62" Flange to flange, 8 bolt hubs and 3/4 ton GM Disc Brakes. The front end uses my original hi steer kit (1994) which places the tie rod and drag link above the springs completely out of harms way. The rear axle is a Currie Iron Jock High pinion D60 with 4.10 gears and an ARB Lock. Brakes are 3/4 ton Chevy. E-brake will be xfercase mounted. Tires are 37" MTR's. both axles were built by Coast Driveline in Ventura CA. The front was off a heavy 1/2ton Ford was cut and rewelded, with outer knuckles spindles hubs from 3/4ton Ford with GM calipers, and my custom mounts. The rear was a buildup with the Currie centersection and 3/4ton spindles, hubs and GM brakes. All of the outer axle parts and lockers were recycled from My CJ5. Good machinery doesn't go away, it just gets rebuilt and reused.

The body is a 4WD Hardware fiberglass complete unit, and the only real Jeep part on this whole vehicle will be the grill.

I've got a long way to go with this one, but the motivation I have received from this site is making the project go much faster. I've got a whole lot of fab work left, I am in the process of fabbing the engine mounts, and body mounts which are both unique to this vehicle. It's all down hill after that and I'm shooting for this christmas for completion, and Feb 09 for finished, ready to go. (paint and all). Hopefully Moab 09

Didn't exactly make that date now did I? 7/12/12 Randy,,, Or 7/12/18 either! Or 1/1/23 but now it runs and drives. See last pages.

I'll keep you all posted on my progress

Pic#1 Drawing of overall idea. This is wHat I'm trying to end up with.

Pic#2,3 Bare frame on wheels.

Randy
 

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#2 ·
Very nice! Lots of money spent there! Monoleafs scare me, you think they will hold up?

Looking forward to seeing the rest of your build.
 
#3 · (Edited)
Finanicing a Project

I've got less than 1/3 the money in this vehicle that I had in my CJ5, When I'm done i'll have about $15-18K total, over about 4 years of actual spending. Which works out to about $4000/ year. I have financed this project largely with monies from junk I've sold on ebay. There is another recent post where I mention selling 2 GV overdrives on ebay, one for $1750, and one for $1650. I had $169.95 total in the both of them, and I got $3150 net out of them. They paid for my OD and my Atlas. I sold my 1975 BMW R90/6 motorcycle that I couldn't ride anymore, which paid for my body and a bunch of small parts. I have a substantial pile of Jeep junk to sell to finish this thing out, sold as needed, and monies directed only to the project, not vacation, or anything else. My wife doesn't even care cause I'm not taking anything away from the family or her as most all the crap was given to me or bought for next to nothing. I carry $200-300 cash all the time, for spur of the moment buys.

I follow the 2 basic rules for business. 1st Rule: "Don't look a gift horse in the mouth". Meaning if someone is trying to give you somethng of value, don't talk them out of it. You'd be surprised how much stuff peole give me!
2nd Rule: "Procurement is more important than Dispersal". That means getting ahold of stuff, is more important than getting rid of stuff. This relates directly to Rule#1, and means you should take time to plan for the highest return on the stuff you have been given. Maybe put a little work into an item to make it worth more.

Here's a hot tip for you younger guys with families, and wives that like to spend everything you make and more. There is "her money", "your money" , and "family money", and it's not wrong to have a "vehicle fund". You have got to keep them separate. There is no reason why you should be spending money you got for selling a piece of junk on diapers. Your salary should cover that. You need a Vehicle Fund that is specifically for that purpose. Most of you older guys reading this know exactly what I'm talking about. You can spend Vehicle fund money for tools or parts or to buy stuff you know you can sell for more, but you never spend it for things that go away, get flushed or have no value to someone else, like Dining out, Beer, Pot, or anything else that won't physically be there tomorrow. You spend Family money, or your money for those things. Also, the more kids you have, the less toys you will have, and the more you will work, just to stay alive.

Here's some numbers. Engine $1225, Trans $100, OD $2750, Transfercase $1000 (craigs list) + $200 to reconfigure input, rear diff housing $300, Tires $200 for 5,Tub $1100, (craigs list) rest of body parts, $1000. Steel for frame and fab $600.

Many parts were recycled from my CJ5, like all of the axle piece parts, brakes, air pump, batteries (2) Radios, antennas, and misc pieces.

I have scrounged a bunch of stuff including some materials and have received some parts from friends (the grill) who had stuff laying around. I have 2 Warn 8274 winches that have to be taken apart and rebuilt but they were free. And I have done some barter in exchange for services like building my axles. I am a vendor for 4wd hardware, so I get a 10% disc, which is easily available to anyone who joins their Jeeps Unlimited Forum.

Everything you see here that is not a store bought item with somebodies name on it was designed and built by ME, including all of the adapters, The entire frame, all body and engine/drivetrain mounts, steering components, suspension mounts, spring perches, and attachments, E brake mount to Atlas, gas tank, bumpers and tire carrier, and all interfacing of the bought parts to the fabbed parts, all painting of the steel (I'm farming the body work out this time cause I want it right), and obviously all of the mechanical work needed to bolt this thing together, and take it apart, about 15 different times. And obviously all of the other stuff I have forgotten with this post

I will end up taking all of the ancillary pieces off the engine and replacing the F&R main seals and the oil pan gasket, along with a new paint job, I'll also paint the trans.

Here's the deal guys. Anyone who thinks a specialized vehicle doesn't cost some money needs to take up watching sports for a hobby. It doesn't matter if you spend the money up front or over the period of several years, you still spend the money. I am amazed at the vehicles being built on this site, and the enginuity that is displayed here. I am not rich, and in fact I'm kind of cheap, and this is more or less just my way of doing it. It all depends on how you want to do things. I started from scratch, cuz I like a good project. It's fun for me, and we all have to pay for entertainment one way or another.

Randy
 
#5 ·
Here's the deal guys. I am amazed at the vehicles being built on this site, and the enginuity that is displayed here.
Randy
Hey hey now..... I don't really need public display of praise and
gratitude..... you could have just told me I'm awesome in a PM

:rasta: No really though... keep up the good work both in the garage and
in the mental understanding on how to run a project balanced in your life!
 
#4 · (Edited)
Well said, I just turned 26 years young on august 24 but I tend to think the same way.

Randy
 
#6 ·
Definately a cool project, and good point about the nice projects on this site. Some are very involved and very high quality. I completely understand your angle on procurment of parts and funding. I am 31 years old and have a shop full of projects and parts. Alot of people get the idea I make a bunch of money because I have all the cool toys, but I am just a cheapass that is good at getting good deals and rebuilding or fabricating what I cant afford to buy. I can build a project for a ton less money than most people due to being a trader/barteror.
 
#7 · (Edited)
Crossmember complete!

finally completed the Transmission Crossmember today. Took a month and a half to completely design and fabricate. Ran into numerous problems with the drawing actually not resembling what was sitting on the floor in front of me.. finally had to drop back and make the drawing right. Then the design came easy.. The crossmember had to do several things. It obviously had to support the back of the trans, but it also had to be adjustable in all directions, and contain the isolation bushings too. It had to go under and just below the overdrive and transfercase, it will support the rear section of the skid plate, and it had to be strong enough to take a pretty good shot and not be damaged. Also the exhaust pipe will be mounted to the top of the passenger side.

As you can see the Crossmember uses 2 more sets of the same 3" bushings as were used on the Engine Mounts. This arraingement should totally isolate the frame from engine vibration. I know it won't completely, but it should work well. The thing is made up of 2 pieces of 2x4 x3/16 wall tube cut and tapered to 2x3 on the outside ends. a piece of .187 wall 3" tube on each end for the bushing mounts, and a SOLID piece of 2x4 CRS for the center section. The whole shebang is adjustable in all three axises, so it will go together easily and I can have my drivetrain aligned with no stress on it. It was all heliarced together.

I ran into one small miscalculation with CV joint clearance over the top of the crossmember. Had to cut it out and install a section of pipe and reweld everything together. Then put it in a LARGE hyd press to unwarp it.

Should be fine now.

Pic#1 drivers side of crossmember showing cutout for front CV joint clearance.

Pic#2 bottom view of crossmember.

Pic#3 view from top.

Randy
 

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#8 · (Edited)
Here's My Motor Mounts (moved)

I was talking about these on another thread and figured I better show you what I'm doing and explain why I'm doing it this way.

This type of mount positively locates the engine in all 3 axises. Something learned from building crawlers. The normal engine mounts locate the engine up and down and support the weight, however they don't really locate the engine very well side to side or end to end.(Vee mounts excepted) This shows up when you pile drive the front end into a ditch while going strait down, or if you roll the vehicle, and the engine flys out on the second rotation.

I had 3" diameter polyurethane bushings made specifically for this. I made the mold and had a buddy cast them. They have 1" dia steel inserts cast in for the bolts to go through. They are cast from 70 duro poly. $30 each. $240 total.

The engine is mounted by the #2 cyl on the right side, and by the #3 cyl on the left side and then there are 2 more sets of bushings on the trans crossmember(under construction) directly at the rear of the OD case. So the entire drivetrain is supported and isolated from the frame by 4 sets of 3" bushings. You'll note the entire weight of the engine is supported by the engine mounts, 375 lb on each, and not cantelevered to share the weight with the trans mounts. I did this because front mounts along with the excessive length of the drivetrain would have placed significant stress on the joints between the trans, od and transfercase, and could cause possible case breakage. The weight on the rear bushings should be around 400 lbs.

These mounts could not have been generated without computer design, as they sit directly on an angled portion of the frame, and in addition the engine sits at 4 degrees in relation to the level portion of the frame. There are no 2 parts which are the same on either mount, and it took me 2 hours to figure out exactly how to even draw it. But it only took me 5 minutes to redraw the right mount when it came out 3/4" too low. Took 4 hours to make the new one.

The center pic shows the right side mount which came out too low and was replaced by one of the correct height. These mounts get bolted to the frame with 4 ea. 1/2" bolts as soon as nut plates are welded inside the frame. The flanges welded to the top of the mounts take the vertical load and prevent the attachment bolts from being subjected to shear loads. The frame tubes get a cap welded over them to close the opening as soon as everything is welded inside the frame. The frame then looks like it was made by miter cutting the tubes, when in fact they are overlapped 16".

I expect some minor vibration transfer to the frame, but I'm also mounting the body the same way, (but with 6 sets of smaller softer bushings) so it should not transfer to the passenger compartment. Plus keeping the idle at 900 rpms will help.

Pic#1 Motor Mount Bushings.

Pic#2 Right Mount

Pic#3 Left Mount

Randy
 

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#9 · (Edited)
Here's my Drivetrain

The Drive train for this vehicle consists of a CPL 858 4BT, a TH400, A US Gear Overdrive, And an Atlas 4.3 Transfercase.

I designed and made both adapters between the trans and OD and OD to Tcase.

Axles are High Pinion Dana 44 Front with 4.10 gears and ARB Locker. Rear, High Pinion Dana 60 Currie Iron Jock center section, with 4.10 gears and ARB Locker. 3/4 Ton Chevy Disc Brakes all around, With Vanco Hydro boost.

Tires are Goodyear 37x12.50x15 MTR's on steel wheels.

Pic#1 DeScrambler Drive Train.

Pic#2 Transmission to Overdrive adapter.

Pic#3 Over drive to Transfercase adapter.

Randy
 

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#12 · (Edited)
This vehicle is being built from scratch, I had no body to start with. The fiberglass body is easiest to use and has many advantages over a steel one. 1st is price, a steel Scrambler tub only is $3000. I got this whole body, tub, fenders, hood, windshield, and tail gate for way less than $3000. It doesn't rust or dent, and your skin won't stick to it in the snow.

The only disadvantage is they will burn if you pour gas on them and light it. I don't intend to do that.

The yellow one in the pic below has been on many, many tough trails in the Western US. This pic was taken when the Jeep was 10 years old just after 4.5 revolution roll and subsiquent redo. It was mainly a paint job, fixing some small cracks in one of the fenders, and a new roll bar. Fiberglass is pretty durable stuff.

Luckily that perfect M170 windshield was always removed before any serious Jeepin', or it would have been toast. Since it was new in box when I got it, I would have been forced to cry.

Randy
 

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#13 ·
I'll be interested in hearing some feedback on how well the motor mounts work for you. The way I see it, many things are a tradeoff between different pros and cons. Your motor is definitely going to be held in position very well and is not likely to come loose on a hard landing etc, however I really think it is also going to transmit a lot more vibration through the chassis. Hopefully your body mounts will dissipate most of it.

I can tell you that I ran my motor for last weekend for about 40 minutes and the way it vibrated surprised me. I'm going to run it as is with the rubber mounts and see how bad it is. I may be back into it over the winter to replace the rubber mounts with the hydraulic/fluid filled mounts.
 
#14 · (Edited)
Slorocco: Mounts like this I have built in the past for my Mercruiser motor and for Chevy V8's used 1.5" poly leaf springs which were very stiff, and did transmit more vibration to the frame than the mounts they replaced. The vehicles were strictly offroad Jeeps so nobody cared.

These mounts are 3" in dia at the flange and 2 5/8" on the step. They have a 1" steel sleeve molded into them for the bolt hole, and are made of 70 duro polyurethane. The trans crossmember also has the same bushings mounting it, so between the larger size, and the 4 sets I'm hoping (you never know for sure until it's tried in the real world) on minimal vibration transfer to the frame...

The frame to body mounts are going to be very similar, 6 ea. about 1.5-2" dia and made of much softer poly, which I'm going to source from the SEMA show next week. I would like 40-50 duro for them.

I am also considering an air bag mounting system like big trucks have for the body, but it may be just too complicated. Could also concievably mount the seats on some kind of airbag suspension instead of doing the body.

One way or another this thing has got to be comfortable to ride in for long distances. Seating comfort, and climate control, along with vibration and noise suppression, are the main issues to deal with. It all has to work together in the end.

Pic#1 Drivers Side Engine Mount.

Pic#2 Passenger Side engine mount.

Randy
 

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#16 · (Edited)
Steve: Thanks for the nod. yes the crossmember was TIGed, and that's why I had to mash it back into alignment with the 150 ton Hyd press. My buddy who has the press, gave me shit for TIG welding it, I should have MIGed it. Less heat means less warpage. I wanted to insure 100% penetration, which I got, and then some, but the back side was "significant weld pull". The driverside tube in the picture closed up(warped) 1/8" after I welded it and wouldn't fit right inbetween the frame rails, so we had to tweek it back to it's original postion.

Most all of the frame is MIG welded, we did that to cut down on warpage. The frame is with in a few thousanths of an inch of being perfectly square. All the parts were cut and machined to length and then indexed together side by side using machined holes to insure that both sides of the frame were indentical. It was a little time consuming, but there is entertainment value here.


All of the mounts and add on stuff are TIG welded because I am better at that. Also on things like engine mounts I want all the penetration I can get for strength. I don't want to make the parts out of huge pieces of steel, and add a bunch of unnecessary weight, when a correctly sized piece that is TIGed together will do. Kind of splitting hairs here on the welding techniques, because they could be MIGed too, but that's the machinist in me rearing it's ugly head.. In any type of welding, fitment of the parts is the most important part in generating strength. The combination of machined parts that fit together and good welding makes for reliable parts. The only problem with MIG welding is Operator error, and not making sure you are getting the penetration you need. With TIG there is never any question about penetration it's always there, and you can see it happening while you are welding.

Pic#1 right side of crossmember.

Pic#2 Showing "L" shaped Foot supporting Overdrive unit and Transfercase.

Pic#3 Fabbed mount to frame, necessary due to proximity of mount to joggle in frame.
Randy
 

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#18 · (Edited)
Solid mount to the trans. No room for another poly mount. but the whole crossmember is supported by 2 more poly mounts. I haven't had much luck machining rubber, although it can be done.

Pic#1 Mould for polyurethane engine/ trans mounts.

Pic#2 completed engine mounts. Note cast in steel bushings.

Randy
 

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#19 ·
Looks great Randy, I'm impressed with your fab skills and I don't impress easily.:beer:

I too, am undergoing a Scrambler project, although mine is currently in the planning stages. I have a Scrambler to start with, don't let that fool you, she's in rough shape.

As I do not posess your fab skills I will be purchasing a frame, TDK most likely.

Which brings me to my first question, suspension. Why the 'glass mono leafs? Although I don't claim to have seen it all, I have never even heard of anyone running Astro leaf springs before. I am intrigued to say the least, as I have not decided on a suspension yet.
Will they hold the weight of the vehicle? Will they flex like a decent coil suspension? Certainly cheaper than a 4-link.

Next question...As I am not a big fan of fiberglass bodies, I have been looking into Aluminum, Aqualu to be more specific. Cost aside, did you look into these?

Last question (for now) Why the TH400 with the GV OD? Why not just a 700R4?

Thanks for your time, keep up the great work, and please keep us posted with your progress.
 
#21 · (Edited)
Doug: The 700R4 can't take the torque of this engine no matter what the builder says. The case isn't strongenough, Look around at some of the posts about 700R4's I have commented on this numerous times. I've seen several destroyed by 4BT's. The case cracks, it's just not strong enough.

The OD is a US-Gear unit. This is obviously to cope with the TH400 not having an OD. The 4L80E was too expensive but would have been easier.

I'm good friends with the guy who used to sell the aluminum bodies. JP Offroad. Just the tub is $3000, I couldn't get a deal of any kind. plus they don't make fenders or a hood, or windshield frame. I got all of that in fiberglass, The only thing Jeep on this whole vehicle is the grill!

I've got less than $3000 in my whole complete body. Fibreglasss doesn't dent, or rust , and is easy to repair, takes paint well. Only negaitve is they will burn if you pour enough gas on them.

The fibreglass springs came from Teraflex, it remains to be seen if they will last. But the guys that have them report no problems offroad at all. Obviously you can't run them into rocks too much, but I'm not expecting to do that, as it never happened on the Mercruiser CJ5 with metal springs and it has been everywhere. The springs are really out of the way. WE'll see.

pic#1 is the "M case" reinforced oil pan/lower bellhousing case for the TH400/475.
Pic#2 is US Gear Overdrive unit with BPM adapter.
Pic#3 is front diff and spring perch, showing the monoleaf attachment. Just couldn't get it any lower, which resulted in having to raise the other 3 perchs to match. Net result; 2" of extra lift I didn't need or want.

Randy
 

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#22 ·
this is a stock wheelbase scrambler? wit h37s so at 103" wheelbase are ugonna have a driveshaft length prob? angle? im courious cause I am gonna use a TH400 behind my 4bt with 3.73 gears and 38s and im gonna be using a OFFROAD DESIGN DOUBLER to help with the lower gearing so Idont cook the trans in the big rocks
 
#23 · (Edited)
I custom built the frame and it is 104" WB. The rear drive shaft is going to be about 17-18" long with a relatively shallow angle due to a HP Currie Iron Jock HP D60. there is also a CV joint in the rear Driveline.

I listed all of my gear ratios on anther post "talk me out of 4.10's" in the tranny section. You can see that the whole thing should work out fine.

My 3rd over ratio is 3.28:1 which translates to 1780 at 60 and 2085 RPM's at 70 MPH.

Crawl ratio is 43.7:1 All 12 gears are about as evenly spaced as you're gonna get.

You need to work out all your ratios on paper to make sure you are going to have decent spacing with no redundent gears, and OK highway speeds. Otherwise you are just making something that isn't going to work well, and there is way too much work and money in one of these Jeeps for this outcome.

You will be at 1980 RPM's at 60MPH and 2310 at 70MPH, which is a little fast.

Just do your homework.

Randy
 

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#24 · (Edited)
Gear Ratios:

Thought I better move this to my thread

I worked out all the different speeds and different RPM's for ALL of the ratios for my trans/tire size, including lo range long before I ever bought any parts.

I was looking for around 1800 RPM's at 65-70 mph. or very close to that.

25-30 mph max in Lo-Range.

Bottom gear in lo-range needs to be between 50:1 and 80:1 depending on what type of offroading your'e planning on doing.

I am using 4.10's axles gears on the DeScrambler and I have got 37" tires. All of my numbers work out. My ratios for the TH400/ US Gear OD/4.10 rear end are as follows at the rear wheels, and Ratios for the TH400 are 2.48:1, 1.48:1, and 1:1. Transfer Case is 1:1 and 4.3:1. US Gear OD is 21%

High-Range
1st 10.17
1st over 8.13
2nd 6.07
2nd over 4.85
3rd 4.10 (direct)
3rd over 3.28

Lo-Range with 4.3 Atlas
1st 43.73
1st over 34.95
2nd 26.10
2nd over 20.85
3rd 17.63
3rd over 14.10

Notice how the ratios from the high-range are evenly spaced as you go faster, and how the lo-range ratios ends up evenly spaced and extending down from the hi-range ratios. Notice also there are no redundant gears, IE gears with very similar ratios, and no big gaps in the ratios.

With 37" tires I am "theoretically" in the sweet spot for the engine at 1790 rpm's @60 MPH, and 2085@70MPH, and my top speed in lo-range is around 25-30mph. 1st lo-range is the "Crawl Ratio" and with this auto trans is 43:1. This is due to the multiplication effect of the torque convertor which is around 2:1 With a manual trans the equivilent would be @86:1.

I am confident of the above numbers as my 12V 6BTA Dodge truck with 4.10's runs at 2050 rpms at 65mph with 31" tires. 47RH has a 30% OD?

Getting the ratios to work out like this is part of the reason for this relatively complex drivetrain as I didn't see another combo with the spacing I've achieved with this setup.

Randy
 

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#25 ·
Randy, I have TH400 US Gear setup 3.55/32" tire combo, all your calcs. are good but you didn't factor the torque conv. loss. I loose on average 300rpm's, puts me about 2400@70mph drives ok but as you said too fast.

I was going swap the rears for 2.76 for all my driving is highway but I may put a 4sp in front of the OD instead. I like the auto but the torque con. slipage drives me nuts. Shifting is like a love/hate relatoinship as well though
Just thouhgt I would throw that out there, your Descrambler is looking great

Greg
 
#26 ·
Nice build Randy.

Just a question on your monoleaf springs, do you think you'll have axle tramp issues with them? They strike me as being a bit softer in resisting axle torque than a conventional spring pack.

I love it that you can build a jeep with only a handful of real jeep parts. The rest of the worlds builders envy the parts selection available to you guys in the US.
 
#27 ·
Dougal: with a spring over axle set up spring wind up is not and "issue" it is a fact, and yes I think the monoleafs will exaserbate the problem. Luckily both the axles are high pinion which lowers the moment arm to the spring considerably, and will lessen the amount of force needed to control the problem.

I have dealt with this issue before many times and there will be one of my anti wind up arms attached to the rear axle. I am reserving judgement on the need on the front axle but have planned enough space on the front right side for one if needed. Typically it wouldn't be needed except if I was going to push this vehicle into the rocks really hard. The rear bar is manditory no matter what.

Here is some first hand info on controlling axle wind up. What actually occurs during axle wind up is as follows. 1. going up an incline, torque builds against tire grip, and the axle starts rotating the opposite way IE top of axle rotates towards rear of vehicle. 2. this continues until the torque has built up to the point where the tire slips, and the axle instantly unwinds. Then the cycle repeats. Typically the axle only rotates a few degrees before the tire slips.(or however much the spring allows)

To control this movement all that must occur is to stop( not dampen or limit) the rotation of the axle. On link type suspensions this is taken care of by the Y bar or upper control links. With leaves it requires an anti wind up bar similar to what used to be called "Traction Masters" in the 60's. Only one is needed to control wind up here as 2 will bind during articulation. The one thing about the design of the bar that is critical is there can be no slack in the axle attachment points, no soft bushings. It must be hard mounted, and a heim joint is used on the front end for axial rotation. All axle rotation must be translated into upward motion of the arm. The upward arm motion is then in turn prevented by the forward bar mount which is in line with the front mount of the spring. The arm is allowed to move freely strait fore or aft by connection with a shackle to the frame. This allows the suspension to articulate freely, and compensate for differences in spring length which changes during articulation. However the front attachment of the arm cannot rise or fall (movement caused by wind up) due to the placement of the shackle mount directly above it. The arm in fact mimicks the travel of the spring, and the shackle allows for minor errors in that travel.

Works great, everyone and their dog copied it, and "improved it", and the only ones that worked were the ones that didn't change anything.

The only Jeep part on this vehicle is the grill. You can build one out of aftermarket parts, but did you know you can build a complete Mini (in any configuration) from aftermarket parts too? When done I will have fabricated better than 50% of this vehicle out of common materials available most anywhere. I could have just bought everything (not really) and bolted it together but where's the fun in that?

Randy
 
#28 ·
with a spring over axle set up spring wind up is not and "issue" it is a fact,.... Luckily both the axles are high pinion which lowers the moment arm to the spring considerably, and will lessen the amount of force needed to control the problem...
I don't follow how high pinion or normal axles affect spring wind up any differently? Can you please explain.

Looking good, can't wait to see it "completed".
I like your attention to detail and extensive planning-- The 7 P's as they say; Proper Prior Planning Prevents Piss Poor Performance!

Grigg
 
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