News: Putting FUN and FRIENDLINESS, FIRST into owning and learning about AMC small bodied cars, primarily Eagles, Spirits and Concords as well as vehicles built in AMC's Mexican subsidiary, VAM.

The AMC Eaglepedia can now be accessed using the buttons found below  This is a comprehensive ever growing archive of information, tips, diagrams, manuals, etc. for the AMC Eagle and other small bodied AMC cars. 

Also a button is now available for our Face Book Group page.


Welcome to the AMC Eagles Nest.  A new site under "old" management -- so welcome to your new home for everything related to AMC Eagles, Spirits and Concords along with opportunities to interact with other AMC'ers.  This site will soon be evolving to look different than it has and we will be incorporating new features we hope you will find useful, entertaining and expand your AMC horizons.

You can now promote your topics at your favorite social media site by clicking on the appropriate icon (top upper right of the page) while viewing the topic you wish to promote.


  • March 28, 2024, 11:26:41 AM

Login with username, password and session length

Author Topic: Project SX4 Evo - SX4 Junkyard to Pro Touring  (Read 10310 times)

0 Members and 1 Guest are viewing this topic.

Offline LeviBetz

  • Eagle
  • **
  • Posts: 36
  • Thumbs Up 3
Project SX4 Evo - SX4 Junkyard to Pro Touring
« on: July 30, 2018, 09:43:07 PM »
    Hey folks, new member here with a fresh project car. Back in high school (I'm younger so that was *only* 8ish years ago) I had an Eagle wagon and always had an affinity for the quirky AMCs and Eagles particularly. I live in Alaska so I'm biased towards AWD cars, but I hate 4wd style pickups
   So about this car. A few months ago a friend posted a photo on facebook of a pick n pull junkyard I had never heard of. Way off in the background was a complete Eagle SX4! I had always wanted one, but wasn't searching for one until there was a 'get it or it gets crushed' style ultimatum. So I drove out there and took a look. Initially I passed it up as it looked real rough. I tried to find a better one locally but all I found was a car that was also fairly rough but the owner wanted five grand for it. After some deliberation and rose colored glasses I decided that I would take the plunge on the junkyard car. I called up the yard, put a small $20 down payment on it and picked it up. Turns out I actually snagged it out from under someone who wanted it a bit too late (sorry not sorry).
   Here are some photos from the yard:







   Okay, so now for the plan. It's still evolving, but basically my concept is the historical fiction of "what if" AMC had decided they wanted to use the "evo" rule of Group B rally to build a dominating SX4 rally car. But in my version of this reality, AMC also decides they want to sell it as a nice performance street car to go after sports cars. So that's what's imforming my decision making process roughly. I don't really plan to make it hyper-period correct, but more to just give it that sort of experience.
   So for the modifications we'll start outside and move in. The body externally will remain largely stock, with some extra bits. I think I'll get a Spirit AMX spoiler for the front (which will require some tweaking to mate up to the flares), and I'll probably delete and clean up some trim to try to clean up the look. Of course anything I do I'll photoshop first, so I'll try not to paint myself into a corner.
   Staying on the look, but moving into the suspension, this will be the largest challenge. First off, I will make it lower. Probably around stock 2wd amc height or a bit lower. To accomplish this, I think the plan of action is to retrofit an alternate spindle which has less distance between the upper balljoint and hub. This will lower the car without touching the spring/shock geometry so I can maintain travel there. Of course to match the spindle change, I'll need to reloacte my lower control arm inner mount point and strut rod mount point. The lower control arm inner mount will by far be the biggest challenge. Moving the mount point will put it right in the way of the steering linkage, so that will need to be re-eingeered too. I can either try to move the whole gearbox/idler arm forward, or retrofit a rack and pinion. It seems like people have success with SN95/fox body mustang racks, and that's an easy mount to fabricate. I'm leaning towards the rack for feel and because the stock system has pretty bad bump steer geometry. Also I'll note that, from my measurments and simulations the stock Eagle suspension has about zero camber gain under bump/droop. So combining the new spindle and relocated mount point, I can change the camber curve and make it handle much better. Don't get me wrong, it totally makes sense why they would design it that way for a tall lifted vehicle, but bad for cornering. Zero camber gain means less grip as the suspension rolls more, so it helps keep the car stable and prevent rollover. Less of an issue once it's low. As for the rear, I'll start by just flipping from spring over to spring under which will drop it a bunch. I've got a rear suspension assembly laying around from a 2013 Subaru STI so I may section that down, retrofit a ford 8.8 center and retrofit IRS.
   Moving onto the drivetrain, this is the spicy part. The plan is big power... hopefully. I'm going to try a little sloppy mechanics style action and see what I can do with a 4.0l. I've already picked up a 'running' craigslist blue light special 4.0l for $150 so I plan to start by building a microsquirt harness and getting it running NA before eventually putting a cheap turbo on it. In the bottom end I plan to get some drop in pistons to mitigate the common piston skirt failure and balance/polish/arp bolt the connecting rods while I'm at it. The other fun piece of the engine plan is to chop the tiny plenum off a 4.0l log manifold and fabricate a sheet metal plenum to use a much bigger plenum volume and throttle body. The stock 60mm and small plenums seem to me to be a significant restriction, we'll see. And lastly I want to make the engine RPM, it's one of my criteria. So radical cam, and try to stabilize the valvetrain as much as possible. LS valves seem possible, I'd like to try to run LS rocker arms as well, but otoh V8 rockers tend to be setup different than I6 rockers, we'll see how it mocks up. I figure if I can use almost entirely LS valvetrain, it'll make the valvetrain pretty safe for RPM. Also LS stuff is cheap as chips. As for boosting the 4.0l and my evidence for this being possible, I'll point to Car Craft's article on Newcomer Racing's turbo 4.0l that did 660hp on a china turbo with stock rods (polished/arp).
http://www.hotrod.com/articles/horsepower-turbo-4-0-amc-jeep/?sm_id=organic_fb_HRN_trueanthem&utm_campaign=&utm_=5a9935bb04d30143165b4320&utm_medium=&utm_source= - https://www.hotrod.com/articles/horsepower-turbo-4-0-amc-jeep/?sm_id=organic_fb_HRN_trueanthem&utm_campaign=&utm_content=5a9935bb04d30143165b4320&utm_medium=&utm_source=
And this engine was built to redline low like a stock jeep which means that cylinder pressures at 712.6 lb/ft and 4600rpm were very high, which is even more strain on the bottom end than I plan. I plan on having the power peak higher up (6k+) which means less peak torque, less strain on the rods/pistons/crank. Of course the big concern with my plan is that AMC I6s (and most 7 bearing 6s) have a crankshaft and camshaft harmonic that has been reported to break cranks/cams. For a 150$ longblock, I'm willing to take that risk and send it. I've really only heard of actual failures with 4.2s and likely 4.6 strokers namely in the applications of the IMSA gremlins and circle track racing. It's worth noting that these engines spend a whole lot more time at that rpm to cause that failure than a street car with ocaisional autox/track use would. We'll see.
   Moving into the interior, I'm not totally solid on my interior plan. I will definitely replace the seats with sportier seats, but the challenge is that I'd like to find something that looks a bit 80s. It seems like what would be the period look there would be old recaros, but otoh $$$$. It seems like the look of 80's sports seats is to have a lower cusion that protrudes forward past the bolsters, while the backrest only has lower bolsters with shoulder bolsters not coming in later and separate headrests with those rad recaro style mesh headrests. I have some cheap NRG seats in my other project car ('73 Super Beetle) and they're *okay* but not totally sturdy. As for colors, etc, I want to do something spicy with some geometric style fabric inserts in the seats, maybe tie it into the door cards. So again, not totally sure what I'll do here.
   As for the trans, I plan to simply bolt in a Jeep AX15 which is actually made by Asin, who happens to use the same design in the Toyota R154 which is a common transmission in modified Toyotas with 2J power etc, so some upgraded parts are available and it seems to handle power well. For diffs, the rear will probably end up being a ford 8.8 at some point either with a live axle with 4 link or using an Explorer center section if I do the Subaru IRS. For the front, S10s and GMC syclones seem to have good luck with their front diffs, which use the same style CV axles as the Eagle (same inner and outer CV), but I may try to match ratios to the stock front Dana 30 and see how it does. I think most of the strain on the drivetrain will be in the rear anyway. Worst case, I'll have to fabricate some diff mounts which shouldn't be too hard.

  Okay, wow that was a rambletron. That's the plan so far. I shot some video of picking it up, and plan to cover some of the build in a youtube series, but I've planned lots of youtube videos I never actually produced hahaha. To finish up this intro post, here's a photo of it tucked away safe in the garage, miles from the car crusher.



*Crossposted to both AMC Eagle Den and The AMC Forum, hopefully that's okay*

Offline eaglefreek

  • Moderators
  • AMC Eagles Den Addicted
  • *****
  • Posts: 4011
  • Thumbs Up 209
Re: Project SX4 Evo - SX4 Junkyard to Pro Touring
« Reply #1 on: July 30, 2018, 10:22:53 PM »
Glad you made over to the forum. I'm Rick Pitz on the Facebook group. Before you get too crazy with the engine, I recall there being an issue trying make these engines rev. Something about harmonics and stuff coming apart.

Found some info, you might have seen it before, though. A few posts down a guy talks about harmonics at 6500 rpm.
https://www.naxja.org/forum/archive/index.php/t-18022.html
1986 AMC Eagle Wagon 4.2L/4.0L head, AW4,NP242, Chrysler 8.25" rear.
1981 AMC Eagle Wagon As Seen On TV  Lost In Transmission


 

"I know he'd be a poorer man, if he never saw an eagle fly,
Rocky mountain high"  John Denver
Click for Fayetteville,TN Forecast" border="0" height="100" width="150

Offline TEagle85

  • Eagle
  • **
  • Posts: 143
  • Thumbs Up 5
Re: Project SX4 Evo - SX4 Junkyard to Pro Touring
« Reply #2 on: July 30, 2018, 11:02:45 PM »
Looking forward to the build. Ive been eyeballing some kind of rack and pinion fabrication. Maybe Electric?  If you can get rid if the steering pump and steering gear it opens up a perfectly sized space close to the exaust manifold for a turbo.   

Offline LeviBetz

  • Eagle
  • **
  • Posts: 36
  • Thumbs Up 3
Re: Project SX4 Evo - SX4 Junkyard to Pro Touring
« Reply #3 on: July 31, 2018, 02:59:39 AM »
Re: crank harmonics. That is a concern, like I said these 4.0l cores are so cheap that I think it's worth the risk for science haha. Maybe I'll contact fluidampr and see if they could make a 4.0l harmonic damper. If you could get more harmonic damping out of the pulley, I'd imagine maybe you could mitigate those harmonics and prevent damage. Acoustically it makes sense, I'm a musician as well so I could see how a fluid crank damper could act to absorb resonant frequencies (kinda like sound deadening and mutes do).

As for turbo hot side and steering, I think what I plan to do is hack up the stock 4.0l header which is honestly quite good and flip the bends around so it aims forward, I'd really love to have the turbo on the passenger side to make intercooler plumbing better and get heat away from the intake manifold. It looks like I have room to run a downpipe down the front side and back up, but with a gearbox steering the middle link may move forward enough to limit that. Either way the hot side doesn't need to be huge, the cold side is more important for turbo spool and such. So ideally I'll have a rack, a small heat shield and a downpipe dropping under the front of the oil pan and back up on the other side. That way my downpipe can be nice and large and dump basically right into where the stock exhaust ran with a big single pipe out to the back.

Offline LeviBetz

  • Eagle
  • **
  • Posts: 36
  • Thumbs Up 3
Re: Project SX4 Evo - SX4 Junkyard to Pro Touring
« Reply #4 on: August 01, 2018, 06:02:12 AM »
Update time. I officially got the title today, so I'm more confident in firing the parts cannon at this thing.

   Today I decided to do some evening wrenching and test some stuff out. Namely I wanted to test moving the hub upwards to just check out the CV axle angle to make sure I'm not going to need to also raise the diff and go really crazy. I also just wanted to start getting stuff apart and freed up. I first tried removing the spring/shock, no luck there as the downtravel limits the spring, so I'll need to use a compressor to get it out. Then I realized I can actually just separate the upper BJ and raise the lower control arm/spindle up. So I did that, amazingly it came apart without too much fuss. Even the sway bar endlink came apart without breaking. I also removed the bumpstop to gain a little extra uptravel. Here are the results of the mockup!

Here's the wheel bolted onto the hub to check fit. This is probably actually lower than I want the car to sit, although maybe I'm misjudging that due to the 205/75/15 tire.


You can see it's really tucked up in there. I'll likely have to find some clearance to open up the wheel well. I may even remove or move the flares, I'm not sure on that.


Here's the distance from fender lip to hub. Keep in mind the flares on the eagle actually extend the fender lip downwards versus a standard AMC fender.


Wide view of the action. Note the top of the spindle tucked into the spring hahaha


Here's the infamous CV axle angle. You can also see that the diff does have a bit of room to move upwards if push comes to shove.


Here's an example of the CV axle angle on a lifted eagle. This is a 2" lift I believe? Seems somewhat similar to mine, just flipped down the other way. I figure if this is fine, then my angle is fine.



Closing thoughts, I thought today's experiments were very encouraging. Other thoughts on CV axle angle, if the spindle swap pushes out my cv axle length, that will also help as the rise will be equal but run will be increased. Also if I do end up swapping to a different front diff, a narrower diff will help this, so I could aim for that. I need to attack a junkyard with a tape measure sometime I think.

Offline mudkicker715

  • Administrator
  • AMC Eagles Den Addicted
  • ******
  • Posts: 3002
  • Thumbs Up 167
Re: Project SX4 Evo - SX4 Junkyard to Pro Touring
« Reply #5 on: August 01, 2018, 09:50:56 PM »
This might work if you got the big joints on there. I think the baby motor had shorter joints.



Manitowoc WI

Offline LeviBetz

  • Eagle
  • **
  • Posts: 36
  • Thumbs Up 3
Re: Project SX4 Evo - SX4 Junkyard to Pro Touring
« Reply #6 on: August 01, 2018, 10:59:49 PM »
They look pretty big to me! A friend suggested I check out the Porsche 930 CV that sandrail guys run. They tend to handle lots of angle well with a 6 ball setup more like an outer CV. I could see it being fairly reasonable to adapt onto the CV flange with it having just a different bolt pattern and an indexing ring thing. But that would be a billet part of some sort I'd have to have made.

Offline LeviBetz

  • Eagle
  • **
  • Posts: 36
  • Thumbs Up 3
Re: Project SX4 Evo - SX4 Junkyard to Pro Touring
« Reply #7 on: August 03, 2018, 07:47:50 AM »
A quick update today, just acquired some more parts. I scored a pair of s10 knuckles with brakes and everything for $30 off craigslist. I also ordered a microsquirt ecu, so once I can come up with a wiring harness to get pigtails from I can start wiring the 4.0l for it's swap. In the meantime I've still got lot's to do with my house so it'll be intermittent progress still.

Offline Blip Downshift

  • Eagle
  • **
  • Posts: 60
  • Thumbs Up 4
Re: Project SX4 Evo - SX4 Junkyard to Pro Touring
« Reply #8 on: December 05, 2018, 10:05:41 AM »
 I like your project.  I am undertaking a similar project with my SX4 (period-ish group B/A homologation special).  Mine came with the iron duke which died so I put in a 258 out of a wagon I had.  Luckily that meant I had all the correct parts.  I have replaced all my bushings with Prothane urethane bushings which I also recommend. I am also building a 79 Spirit into a rally car so I have lots of Spirit suspension parts that I can use.  I am lowering mine down to the stock Spirit ride height using the Spirit front coils and the rear spirit leaf springs and mounting points.  For your rear, Al at control freak told me that the Spirit 4 link setup that they make will fit the Eagle.  Not sure if that is out of your price range but your could look at it and get an idea of how to make a 4 link setup for your eagle.  If your going to put serious power through the drivetrain, the Ford rear end is a good choice and is the easiest way to get rear disc brakes.  Also, don't discount the idea of going to an AMC 20 with the proper track width.  They are easy to find, relatively strong (much stronger than the AMC 15 you and I have) and have plenty of performance parts available.  There are 258/242 Jeep companies out there that do high speed desert racing so the technology is there for a relatively powerful, fun inline 6 engine.  Just remember, the AWD/4WD system AMC built (no matter the trans, diff, or transfer case combo) will eat up your power to wheels much more than a newer AWD car with modern all-in-one transmission and transfer case (i.e Audi's Quattro system, Subaru's AWD, or Toyota's Alltrak).  For increasing the RPM range, 505 performance makes a roller cam kit that goes into 258/242 inline six engines that will raise the red line up to 6000 RPM.  With that aggressive of a cam though, the car will probably idle poorly.  They make less aggressive roller cam kits also with better everyday drivability at the expensive of some lost top end.  505 performance also makes a turbo kit for the 258/242 but I am not sure of the price.  Roller rockers are also a good choice to increase RPM range capabilities but you may want to stick to AMC/Jeep parts as they are tried and true and guaranteed to fit.  I'm sure you've already looked at this but take a good look at your car's rocker panels.  They tend to rust out and can be a pain to find replacements.  Either way, good luck and I look forward to hearing more about this build.

Offline LeviBetz

  • Eagle
  • **
  • Posts: 36
  • Thumbs Up 3
Re: Project SX4 Evo - SX4 Junkyard to Pro Touring
« Reply #9 on: December 28, 2019, 07:36:55 AM »
(crossposted form TheAMCForum post)
    Oh boy, so it's been ages since I updated this thread, obviously over a year! Unfortunately not much more has happened to the car. I've been caught up with home projects, working on my girlfriend's car, etc.

However, I do have a shortblock together! So first, I stumbled across this late model 4.0l on craigslist listed as "scrap metal and engines" for FREE! So I picked it up, along with the AW4 and NP242 it came with! I later traded the AW4 for a Ford Explorer IRS 8.8 diff.


When I opened it up, look how clean it is!! Unfortunately it is a 2000, which is right when they had cylinder head cracking issues. So we'll see how this goes.


The engine turns over no problem, but unfortunately the cylinders do have some rust in them, otherwise they're clean. No wear ridge at all, and a visible crosshatch.


Ultimately I decided to just run the stock bore and just dingle ball hone it to clean it up. The plan is to simply run cast iron rings and let it rip.


I didn't get many photos, but I decided to pickup some forged scat connecting rods (6.125" length) and simple replacement hyperutectic pistons. The forged rods were almost as much as just arp rod bolts alone! I think they're around 250 bucks IIRC. The pistons were very affordable at around 150$ with rings.




    All that got assembled into the stock block with new rod bearings. The stock crank stayed in place with it's original bearings too. I put a crower cam in it too, but that may or may not stay as I think I picked the wrong cam there haha, it's way to crazy in spec, we'll see how it runs. The piston rings got the gap increased, I can't quiiite remember what to. I want to say .028"?

    Now here's where it starts to get crazy (again). At first I thought the harland sharpe rockers were a bit too expensive, so of course I dove down a rabbit hole and developed my own setup haha. This is what I came up with. Big block chevy rocker arms give a 1.7 ratio and fit well and pattern good on the valve tip. I was able to find these rockers used locally for cheap. The studs are 5/16-18 to 7/16-20 conversion studs, I believe fitment for a ford cleaveland. Then the guideplates are for a LS. The LS has the same 1.9" valve spacing, in fact a LS head would fit great if you could weld two together and move the bolt pattern around ever so slightly. Finally the pushrods are for a Ford 300 and happen to be the right length. Now I may have to go to a purpose built hardened pushrod, but the 300 uses guide slots in the head and the pushrods are pretty hard. So I think it should work out just fine. They're virtually a whole order of magnitude cheaper than custom hardened pushrods. I'll inspect after it first runs.

Here's my homebrew mockup pushrod on a homemade mockup stud


And finally the final pushrods and polylocks on a mockup spring


Still plenty to go on the valvetrain, I still haven't put the head together for the last time, and I need to figure out a valve cover solution for the polylock clearance. I'm not a huge fan of the look of some of the available valve covers, so I think I might have a go at modding a stock cast valvecover to clear. Again, the goal here is to get this engine together as cheap as possible. This is all very experimental, so I don't want to be out too much cash if something catastrophically fails.

    Meanwhile, I chose my turbo. I went with a borg warner s366 oem style clone. I chose this one, honestly by copying the turbo choice from this Hot Rod article: http://www.hotrod.com/articles/horsepower-turbo-4-0-amc-jeep/ - https://www.hotrod.com/articles/horsepower-turbo-4-0-amc-jeep/ I googled the casting number and found out what turbo it was. Of course looking at the compressor map it works out to be right in the ballpark of what I need. People also use them on Hondas, 2JZs, etc. So it seems like about the right size turbo to take around 200-300hp and amplify it into 600-700ish.
Here it is just plopped on top of the mess of vacuum hoses currently occupying the engine bay.


Then for fun I really sketchily milled the AMC logo onto the front cover in my drill press hahaha. I used a 3d printed bracket thingy to clamp the front cover in my little XY vise. This allowed my to mill the angled part. I super wouldn't recommend this. It was like 80% of the way through that I remembered the drill chuck was just a taper fit with no drawbar hahaha.


More recently I picked up the door and fender I need from a local junkyard. I also scored some Marchal fog lamps and a center gauge pack that I was missing.








I may modify these gauges later. I kinda want to see some funky 7 segment LCDs in there for maximum 80s retro vibes. Maybe I could build some arduino powered ones and show boost, etc.



    Now, back to suspension design. I've gone around and around on suspension design. More recently I was inspired by a mcpherson strut conversion kit I saw at SEMA for early mustangs. So I decided to dive in and see what I could do. This time I decided to try 3d scanning the front fender area in order to get a more accurate measurement. To do this I marked out a known dimension on the frame rail and used photogrammetry with meshroom to scan the area. Once scanned I was able to use the photographic textures to scale it to the marks I had written on the frame. The dirt and rust really helped get a very nice scan first try! Honestly I was surprised how well it all worked out. Once scaled and aligned, I was able to measure a dimension virtaully and confirm it in the real world. I should have started with this!

Here's the 3d scan of the stock parts


    Ultimately I went (again) around and around on the various ideas I had previously explored. I explored the mcpherson strut idea, which seems to be plausible, but ultimately it has a lot of drawbacks and doesn't seem like the best bet. Finally I believe I've come upon a good final solution, and that is... my original idea. Kind of. With the new, more accurate measurements I was able to explore the idea of using an S10 knuckle more thoroughly and it seems to be the simplest idea.

S10 Knuckle as I plan to use it


    The plan with the S10 knuckle is to utilize the S10 lower ball joint as the upper ball joint (maintaining it as the compression loaded balljoint), and a chrysler K772 as the lower ball joint (commonly used in mustang ii suspensions and for circle track stuff). The lower ball joint will be flipped so the shank is facing upwards such that the lower control arm can angle down slightly. This helps the camber curve while maintaining a decent roll center. A coilover will be mounted off the upper control arm near the ball joint, connecting to the chassis in the stock spring perch location via an adapter. The benefits of this are fairly massive. I get to have the camber curve I want, that's number one. But also important is that I can run a less severe KPI (in the front view). Kingpin inclination or steering axis inclination leads to camber loss when the wheels are turned, that's no good for contact patch. This is one of the downsides I discovered of mcpherson strut, but benefits of double wishbone. Also, because the S10 knuckle is so much smaller (and lighter btw) than the Eagle knuckle, I can tuck it inside the 16" wheel that I aim to be able to run. This allows me to run a more modern high(ish) offset wheel around +35mm. That way I can have a nice zero scrub radius, unlike the mcpherson strut or stock knuckle based designs allowed (they ended up with around a 3" scrub radius, ouch). Bump steer is a concern, but it looks like it's pretty close and I think can be handled experimentally once I get the knuckle mocked up in place and can cycle the suspension.
    Of course the knuckle will have to be reamed to accept the ball joints in the configuration I want, but that shouldn't be difficult. The upper control arm inner pivot will be moved down to just next to the frame rail, this makes mounting incredibly convenient and easy to jig up. The other beautiful thing is that I can utilize a 7.5" circle track upper control arm to provide an innver pivot and nearly direct bolt on ball joint (the S10 bj should bolt into two of the K6024 bolt holes, with the others easily redrilled). From there brackets can easily be jigged up and fabricated to mount a coilover to the upper arm. As I have the 3d model of everything it'll be a simple matter of 3d printing a jig to locate said coilover mount tabs. For the lower control arm the plan is to build a simple control arm extension bracket that will mount the K772 threaded sleeve in the correct place. For this I've already 3d printed a jig that locates the K772 for mockup. It's incredibly gratifying to take dimensions measured in real life, compared with a 3d scan, and then 3d printed and to then bring it full circle when the part bolts directly in place. The lower bj bracket fit first try and bolted straight on. This will of course be turned into a steel bracket, likely built from .25" plate, which will get bolted and welded into the control arm. The track rod will probably be converted to use a uniball spherical bearing in place of the squishy rubber bushings.

Lower BJ bracket attached to lower control arm


Finally, some notes on CV axle stuff. Being that I have this 3d scan now, I can accurately experiment with CV axle angles and what not. It seems like most of what I see suggest that outer CV joints can handle about 50-60 degrees total angle. With the stock position that's asking a lot of the CV. So I'm thinking I'll fabricate brackets to raise the diff and mount it to the chassis instead of the engine. This will allow me to move the diff up without having to worry about how it moves with the engine. It's looking like with some minor clearancing of the crossmember mount studs I can move the diff up 1.5" giving me about a 10 degree cv angle at ride height. This goes up to about 20-25 degrees at full bump. For this I think I can run 30 degrees of steering angle, which combined with the fairly short wheelbase nets about a 37ft turning circle, which doesn't seem too bad. Stock is about 32.6 ft. So again this shouldn't be too bad of a fabrication project just involving fabricating some brackets to weld onto the chassis like most awd vehicles (or the pickups the Eagle is more closely related to). The only concern is oil pan clearance, but even if I have to clearance that and install some drain tubes, I gotta do what I gotta do.


That brings us up to date. It seems like a lot after writing it out, but realistically progress has been slow being that I've had over a year since the last post. I hope all of this is interesting! I've been having a blast learning about and developing this front suspension. Nothing like a project with well defined goals to force you into growing and learning.

Oh and one last thing, I 3d printed a nice adapter for this sweet old Audiovox cassette deck that came with the car and works perfect! I can't wait to cruise down the road blasting Aerosmith's Get a Grip on cassette.


Oh, and finally finally, I do have some videos of this stuff on my youtube channel Projects Forever, so check it out (https://www.youtube.com/channel/UC4NGx_EWEXTAF5uyJQRbOHQ) I believe I left off at tearing down the engine. I should have some more coming soon.

Offline RallyEagle

  • Eagle DL
  • ***
  • Posts: 158
  • Thumbs Up 9
Re: Project SX4 Evo - SX4 Junkyard to Pro Touring
« Reply #10 on: December 29, 2019, 09:23:43 AM »
Fantastic project! Press on

Offline Blip Downshift

  • Eagle
  • **
  • Posts: 60
  • Thumbs Up 4
Re: Project SX4 Evo - SX4 Junkyard to Pro Touring
« Reply #11 on: January 06, 2020, 11:55:56 AM »
Good to see you back on the project.  I understand how projects can get delayed, it happens to everyone once and awhile.  I like your front suspension mods and and very interested in how they turn out.  The 3D scanning and modeling really take some of the mystery out of fitting new parts.  It is also nice to see someone else building a SX4 Eagle for road performance rather than off-road rock crawling or over-landing (although I like those too).  You said that you traded your AW4, what transmission/transfer case combo are you planning on using?

Offline LeviBetz

  • Eagle
  • **
  • Posts: 36
  • Thumbs Up 3
Re: Project SX4 Evo - SX4 Junkyard to Pro Touring
« Reply #12 on: January 24, 2020, 05:54:57 AM »
Thanks for the kind words! After today's discoveries, I may not have to raise the diff after all! Over the past few weeks I've 3d printed and assembled the needed pieces to mock up the front suspension and cycle it through it's travel.

Once my balljoint reamer came in, I reamed the S10 knuckle for the new tapers (flipped taper on the lower, larger taper on the upper), and mounted it to the bracket.


Today I got around to mocking up the upper control arm and cycling the suspension! Not pictured is the 3d printed UCA mount studs. I printed a simple cylindrical part that allowed me to mount the UCA in place with just sheet metal screws (temporarily of course). That was sturdy enough to move the control arm through it's travel. This is at approximately ride height.


Here you can see the CV angle, just roughly measuring it with the angle finder it's around 12 degrees, which doesn't seem too crazy. Also, obviously this is my standard Eagle axle, and it seems to fit nicely still, so I don't think I'll have to go to the S10 axle. At full droop (the axle approximately flat) it has maybe a 1/8" inward clearance, and then at full bump it seems to have the tripod joint fully engaged still.


So it's all looking very good! Like I said I cycled it today, so I measured the camber curve, and it's a little too aggressive. I think I need to ream the upper ball joint stud a bit more. But I have a somewhat janky ball joint in there right now, so I think I'll pickup a new one from the parts store this week. Other than that, I didn't notice any crazy bump steer. Suspension travel and ball joint angle seems good for the travel range I want and coilover I plan to run, even the bump stop is falling right into where I want it. I'll cycle it again this week and use something to check bump steer through it's range of travel. Other than that, and not quite as fun there is a fair amount of rot in the frame rail, so I will have to address all that. Ugh, rust repair in the home shop is no fun. Oh well, what has to be done has to be done! 

Offline LeviBetz

  • Eagle
  • **
  • Posts: 36
  • Thumbs Up 3
Re: Project SX4 Evo - SX4 Junkyard to Pro Touring
« Reply #13 on: January 24, 2020, 05:58:40 AM »
You said that you traded your AW4, what transmission/transfer case combo are you planning on using?

I've got an AX15 I picked up along with the NP242 that came with the AW4. So the plan is to rebuild the AX15 (it's pretty high mile) with some upgrade parts from marlin crawler (need to confirm they'll fit). I've also been thinking about maybe trying to pickup a r154 or ar5 and use that gearset and midplate. But that's a pretty halfbaked thought for now. It'll definitely be an ax15, keeping it 5 speed manual.

Also, someone on my AMCForum thread pointed out that if my 0330 head is cracked and was the culprit of the water in the engine, the rust would be in numbers 3 and 4. I checked tonight and that is the rusty pair. So it looks like I'll definitely need a new head. I'm thinking of maybe having a go at porting my spare Renix head I have, but that may not even be worth my time.
« Last Edit: January 24, 2020, 06:03:30 AM by LeviBetz »

Offline v0rt3x86

  • Eagle Sport
  • ****
  • Posts: 459
  • Thumbs Up 16
  • Day at the Beach
    • MySpace
Re: Project SX4 Evo - SX4 Junkyard to Pro Touring
« Reply #14 on: August 09, 2020, 04:13:27 PM »
Any updates? I busted a coil spring and since they don't make them anymore, I'm open to alternative options - especially when parts start coming from the yard.

Online vangremlin

  • Administrator
  • AMC Eagles Den Addicted
  • ******
  • Posts: 4412
  • Thumbs Up 212
Re: Project SX4 Evo - SX4 Junkyard to Pro Touring
« Reply #15 on: August 10, 2020, 12:04:43 PM »
Any updates? I busted a coil spring and since they don't make them anymore, I'm open to alternative options - especially when parts start coming from the yard.

Have you checked with ESPO Springs and Things for new coil springs?  I'd reach out to them and see if they can set you up with a pair.  Good luck!

https://www.springsnthings.com/coil-springs.htm
1981 Kammback 258 - "Pepe"
1980 Coupe 258 - "Ginger
1972 Gremlin X 304
1978 Gremlin 4 cyl 121 - sold
1964 TBird 390 - sold

Offline Taylor

  • Administrator
  • Eagle Sundaancer
  • ******
  • Posts: 851
  • Thumbs Up 34
Re: Project SX4 Evo - SX4 Junkyard to Pro Touring
« Reply #16 on: August 10, 2020, 01:40:07 PM »
As for the springs, I used Espo Springs and Things. They have or can get all of the suspension parts ( ball joints, bushings, springs, ) except stuff like control arms.
https://www.springsnthings.com/
You can also ask for a estimate for a front end rebuild kit. I think I have a estimate for one in email somewhere. Request ball joints and all bushings.
« Last Edit: August 10, 2020, 02:52:54 PM by Taylor »
2010 Toyota Rav4 pack mule
1985 AMC Eagle Limited Wagon 🖖🏼🦅
2020 Honda Africa Twin the long haul trucker

Offline v0rt3x86

  • Eagle Sport
  • ****
  • Posts: 459
  • Thumbs Up 16
  • Day at the Beach
    • MySpace
Re: Project SX4 Evo - SX4 Junkyard to Pro Touring
« Reply #17 on: August 10, 2020, 09:12:04 PM »
Not anymore. Moog stopped making them.

Offline amcfool1

  • Eagle Limited
  • *****
  • Posts: 638
  • Thumbs Up 31
Re: Project SX4 Evo - SX4 Junkyard to Pro Touring
« Reply #18 on: August 10, 2020, 11:32:44 PM »
hi, coils are available try ESPO   gz

 

SMF spam blocked by CleanTalk