Rock Lizard/Weekend Ultra4(?); blown LS, 40s, tons, bypasses, etc.

[csutton7]

To bad you weren't closer I have a 4l80e coming out of my willys truck(rebuilding a newer one or I should say having a newer one rebuilt) that I'd let go of.
Glad to see you're making progress, keep it up.

 

[snivilous]

Eh, sometimes you have to cobble shit together and get it barely working so you can have 15 minutes of fun with the project. There’s something about putting in all those hours and finally ripping down the street and back that gives you a newfound motivation to actually finish it right. Stabbing the go pedal a couple of times makes you think “imagine how awesome this is going to be when it’s finished right” instead of “I’ve only got 900 things to do before I can enjoy this”.

Man ain't that the truth. Right now it feels like a running vehicle that needs some work to run better, before this it was a never ending project. Building stuff is fun, but a few minutes of actual driving and knowing it's possible to get to the end of the tunnel creates a hell of a lot of motivation!

 

[eat.sleep.wheel]

That's cool. I've taken a lot of sketchy stuff to the end of my road and back just to get some motivation.

 

[snivilous]

It works!!!

Been over a year since I last posted about the buggy or have done anything considerable to it. Every now and then I'd dabble with something, but it was months apart and just a handful of hours of work. With the weather getting nice and getting motivated from watching the Wrecked Gear and Wheelin Out West YouTube channels, I did one of my big pushes over the past week. I wanted to take the buggy wheeling, and it didn't have to be fully functional but I wanted it to hit dirt. Since building the buggy Ive become an advocate that modifying something is a lot easier than starting from scratch. If you can make modifications in a week or two or continue to enjoy the vehicle and remember why it's fun, that's a lot easier than spending months or years with nothing to enjoy. And now that the buggy drives, everything else feels like an easy weekend to work on and upgrade and then go and enjoy that upgrade and not get burnt out. It took me 4.5 years to get to this point and being very burnt out and not touching it for months at a time.

But I wanted to go rock crawling this year, so the past week I went hard.

The two things the buggy needed was to be wired and to install an electronic brake booster. It's amazing how many configurations this vehicle has been through considering it drove around the block about 3 times before this.

I did not like the manual wilwood setup I had, and I recently built a 1978 Toyota Hilux and it taught me two things mainly: wiring and that the current OEMs Bosch ibooster is insane. I cut out the wilwood setup and installed the ibooster brake booster, which uses an electric motor to provide brake assist and if that fails then it acts like manual brakes. The wilwood setup needed a huge pedal throw and even then was a struggle to slow the vehicle down. The ibooster is quite a bit larger but I got it to fit (no pictures right now) next to the steering wheel, and all it needs is 12v power. And man does it work! I can lockup the 40s like they're not even there, and this is using a 5:1 pedal ratio vs the wilwood was a 9 or 12:1. I also need less brake pedal motion, requires minimal effort, and as long as the ignition is on I have full brake boost.

The second thing was wiring. A few months ago I made a battery tray to put the battery between the two seats. I now needed to run all the electronics to the back, and figure out how to mount everything. I bought a switch pros to help with wiring, and for the most part the switch pros should help alleviate needing relays or fuses for anything. I also stripped down my Holley engine harness and removed any excess wires and tidied it up a bit. I also installed my 7" digital dash and a kill switch in the front.

Like I said, the Hilux taught me a lot about wiring. Everything is covered in fabric sheathing, I use Delphi connectors where ever feasible, heat shrink splices when needed, and all automotive grade wiring. Still a bit of a cluster but slowly getting there. I ordered a fuse block but turned out it wouldn't accept the Delphi pins I was using for some reason (seems like every time I order a bunch of wiring something inevitably doesn't work with everything else). As I said I'm trying to keep relays and stuff to a minimum, so right now the plan is to have the fuel pump off a relay because the Holley can control the pump (as opposed to switching it to the switch pros) and then I have a 75A relay for the radiator fan, and will probably install a second fan and relay.

The front of the battery box has the switch pros block mounted, then below that is the big relays and where the fuse/relay block would go if I had the right one, and below that is the ECU. So all the electronics are between the seats and easy to access and keeps the wire routing fairly easy.

With the brakes installed and wired in I went for a quick drive around the block to verify the brake booster could actually handle the 40s. This was the first drive in over a year.

I think that was Friday night. So I now had Saturday and Sunday morning to button everything else up. There was a fairly short list but a lot of side journeys to get it to a safe driving state. Since it's a new vehicle I am extremely conscious of all the fluids running around, and before I was going to let my wife ride in it it needed at least floor boards and some level of shielding from everything. This isn't really an issue on most vehicles, but in a tube chassis, especially rear mounted radiators, there is a lot of lines running past your seats with hot fluids. I have gas, coolant, atf, and engine oil all with pressure and return lines going past the seats, and have had radiator hoses burst before so I threw some floor boards together to at least shield the bottom/front of the passenger area. No pictures of that right now besides this awesome origami piece I cut that formed the passenger foot well.

There was a bunch of other miscellaneous things like the mufflers had been tacked in place in the foot well, so for now I just removed the mufflers and ran 3" exhaust tubing to the back of the chassis. The steering hydraulic reservoir was bungee corded in place so made a bracket for that. I welded the rear diff. I did more wiring. Installing the seats. Fucking with the brake pedal. It just went on and on. Saturday was an all day event, and even Sunday before taking it out I worked on it from 8am until the moment I decided it was good at 230pm. Thanks to my wife and neighbor for helping on Sunday too. My neighbor also came down with his UTV so if I broke (highly expected) someone could tow us back to the trailer.

There's lots of wheeling where I live and why we moved here. But I wanted to go to the coolest place, Sand Hollow, which is a 45 minute drive away. I could've gone to a local place about 10 minutes down the road, but I was committed that if it was going wheeling this wasn't for a little test drive, I was going for the full experience and actually running a trail.

After a quick test drive around the neighborhood to make sure everything was working correctly, we loaded up and got to sand hollow at 4pm or so. This was the first time it had ever left a short distance from the house, and the first time it had ever been on dirt since I started building it 4.5 years ago! I had a ton of butterflies.

The plan was to do a loop where we go up an easy trail called west rim, and then pop out at some sand dunes and loop back to the truck. The buggy is currently 2wd because my front RCV axles are 35 spline but the stock carrier is 30 spline, and I haven't bought gears or lockers and I threw out the stock shafts already. West rim is an easy trail so figured 2wd would be fine.

And find it was! The buggy ran absolutely great with no breakage!

 

[snivilous]

PART 2:

Everything worked absolutely awesome! I could not ask for a better first drive. It handles extremely good, which has been a worry of mine and was the main reason I got rid of my old racecar and started building this. In the corners it's extremely flat even without sway bars and sitting a couple inches higher in the back than I want. That right there is a huge win. The suspension needs a lot of tuning, in some regards it felt pretty good but in the small chattery washboard it's pretty brutal, though I think that can be tuned out.

I tried to avoid messing with the shocks much, but I did stiffen up one of the front bypass tubes all the way since we bottomed out the front once and I don't have front hydraulic bump stops due to packaging. I might try to fit some now, but the plan was to use the bypass bump zone as the bump stop. The front only has 8" of up travel though, so might be inevitable to shove some bumps somewhere just to help it out. The rear I opened up the bypass tubes all the way, and even then I was only able to tap the 2" stroke bumps one time. As I said, the rear is sitting a few inches higher than I want and I need new springs to lower it, its strapped at 24" and has tons of up travel and a lot of shock to handle all of it. The rear end in the chattery stuff felt like it kept stepping over to the side, I think the rear end alignment might be out causing that.

The brakes as I said are insane. I need to get a proportioning valve but even without it the thing can stop violently fast with no effort. The pedal stroke is also less than I expected so I'll remake the brake pedal and help the ergonomics a bit. It's left foot braking so need to get used to that too. I also have a hand brake I need to add, though I might go to twin hand brakes and set them up as cutting brakes so I can individually lock each rear tire and help it turn faster, still undecided on that. Right now with the rear end welded that obviously doesn't matter, but when I get gears will need to decide what kind of locker setup I want and if it's not a spool then cutting brakes would be neat.

The steering wheel is tiny and dumb but worked fine. I'll probably extend it 3-4". I wish I had a 2 turn wheel, this one is 3 turns lock to lock. I really like the 2 turn setup on our UTV, not sure if that's just a different orbital or if the pump would need to change too. I also want to get a 9" steering ram, my current one is 8" but I don't have a lot of steering angle (well the same as a super duty has). The RCVs will allow me a lot more turning angle so hopefully a new ram is a direct plug and play so I can get another few degrees of turning. It's not bad right now, but I have a 119" wheel base so it's pretty long.

The digital dash is cool, I didn't fuck with it at all so need to configure it. When the sun hits it you can't see anything either, so hopefully it can get brighter. I was worried the tune I currently have wouldn't work great since it had a bad stumble off idle, but after driving it for a few hours it felt really good and I think the ECU learned. Will need to play with tuning it which I'm excited for after everything I've learned from tuning the tundra.

The engine maxed at 200F, this is with the single radiator fan and I plan to run two. No idea on the other fluids, but fuel pressure and oil pressure were fine the whole time. No idea how much boost the supercharger was making. Overall I had minimum telemetry and just kind of sent it. I got the last parts for the stroker engine the other day, so if the 5.3 blows up I don't really care. Because I said that it'll probably run forever too. But the engine seemed totally happy, the trans seemed happy, it all ran really well. The only issue I had at all was the serpentine fell off twice which I was expecting. The tensioner setup I have sucks at the end of the day, so I'll have to fix that. The fact it worked as well as it did surprised me, fell off in the beginning and right at the end.

I think that covers all the mental notes I took! Extremely happy I made this push and pounded out so much work in a couple days. The buggy ran amazing and I can now do little tasks here and there and make it better and start going wheeling with it. I should have 4wd within the month I hope, and will be tuning in a lot of stuff I mentioned.

I hardly took any photos, so I'll grab some more soon and show more of a thorough walk around of everything.

 

[JohnnyJ]

I did not like the manual wilwood setup I had, and I recently built a 1978 Toyota Hilux and it taught me two things mainly: wiring and that the current OEMs Bosch ibooster is insane. I cut out the wilwood setup and installed the ibooster brake booster, which uses an electric motor to provide brake assist and if that fails then it acts like manual brakes. The wilwood setup needed a huge pedal throw and even then was a struggle to slow the vehicle down. The ibooster is quite a bit larger but I got it to fit (no pictures right now) next to the steering wheel, and all it needs is 12v power. And man does it work! I can lockup the 40s like they're not even there, and this is using a 5:1 pedal ratio vs the wilwood was a 9 or 12:1. I also need less brake pedal motion, requires minimal effort, and as long as the ignition is on I have full brake boost.

Interesting. I'm retrofitting a remote hydroboost into my buggy now. I'm no looking forward to the plumbing. Interested to hear more about this.

 

[snivilous]

Interesting. I'm retrofitting a remote hydroboost into my buggy now. I'm no looking forward to the plumbing. Interested to hear more about this.

I went ahead and made a thread detailing everything: iBooster Electric Brake Booster

 

[WaterH]

Sounds like a really good time. I sucks it wasn’t four wheel drive, but I guess it didn’t matter.

 

[chaplinfj60]

how close is your feet to the exhaust and do they get hot?

 

[snivilous]

how close is your feet to the exhaust and do they get hot?

Very close, the floor is an inch or less above the exhaust. Passenger side also has aluminum radiator lines parallel with the exhaust. Floor is 1/8" aluminum. We both had tennis shoes on and long pants, I didn't notice any heat at all and the wife didn't mention it but I didn't ask, it was also 70 out so not super hot and everything is still pretty exposed to let heat out.

My plan is to insulate the exhaust and flooring, I was suggested a place called Thermal Control Products. And the radiator lines I will switch to single piece fabric covered AN lines which should help the passenger side.

 

[chaplinfj60]

very good. thanks

 

[snivilous]

Time for an update before I forget everything and since I have so many photos to keep straight! After the last post I ordered gears and lockers and a bunch of other shit. The past 6 weeks has primarily been dealing with gearing the axles.

But to start out, I did do one quick follow on trip to do a bit more testing of things.

The stability has continued to impress me, and from my limited flex testing it seems to flex fine. I'm able to do donuts with limited body roll and it feels very controlled. My somewhat unique/extreme rear end geometry doesn't seem to be hurting it so far (knock on wood). I'm sure it'll get a sway bar eventually, but I'm impressed so far with how it feels with no sway bar. I'd like to drop the fuel cell in the future and that should lower the CG quite a bit too. Right now it seems to have settled on 8" of up travel which is what I wanted. That results in a 21" belly height.

A long time ago I had one of the rubber cooling lines explode (don't put rubber lines between your thermostat and engine!), and ever since then have been extremely wary of lines failing and protecting the occupants. So I went ahead and ordered some AN20 lines and fittings to replace the extremely complicated rubber/aluminum lines I had before. I also bought the remaining parts to plumb the intercooler/steering cooler system and a four pole kill switch.

Out with the old! RIP old lines, these were the first aluminum things I ever welded!

And in with the new!

Will pretty it up later, but went from a dozen-ish connections to four! And can easily reconfigure the tube routing now.

Another thing that needed fixing was the belt tensioner and routing. The original tensioner seemed extremely flimsy and would visibly rotate out of plane with the belt. I went ahead and bought a different tensioner from a LS1 corvette as I recall, and went about modifying the tensioner/alternator bracket. I first milled off the old tensioner mounting plate so I knew I had a good flat reference face relative to the head and alternator.

This picture is kind of hard to see, but I then made a new bracket/mounting face that is welded to the tube stand off and then I boxed in the sides as much as possible to keep it stiff.

There was then some small things to touch up, like the new tensioner had a ribbed pulley so I swapped the old smooth pulley over but of course that didn't fit so I had to turn it down on the lathe to clear the tensioner arm. The head also seemed gummed up so I made a sweet 8" deep tap to fix that, etc.

The end result is the "new" belt routing, which is the same as before but with (what appears to be) a much stouter tensioner. I also dropped the belt size a bit which is now an absolute bitch to install, but the tensioner doesn't max out just sitting there which the previous one was doing. I only have maybe a half mile on this setup, so time will tell if this works, but due to the higher belt tension and correcting the misalignment of the tensioner I'm confident this will work.

Other things I did was finish welding the mounting bracket for the power steering reservoir, and at the same time converted it to a nipple connection. This did pain me, since I had converted it to AN a long time ago, but after looking at everything if I ran AN fittings they would add so much length versus hoses and barbs that it was gonna make routing annoying--plus the cooling pump is plastic with barbs so no real way to convert that to AN. So I unconverted both the supercharger and the reservoir back to their original barbed fittings.

I then took the cooling reservoir and converted it to barbs.

And lastly converted the little radiator I bought to nipples also. This I ended up somewhat awkwardly mounting in front of the other radiators (I think it's intercooler, then transmission, then main radiator in a triple stack on the drivers side). But that was the best place to mount it and get good airflow all the time without adding additional cooling fans. Plus with this radiator and the reservoir in the back, it helps with packaging since after a winch and shock brace go up front it'll be very tight.

I then added the reservoir mounting bracket which is right behind the driver's seat. The cooling lines run from the steering pump/supercharger along the left side of the transfercase, through the pump which is next to the lower link mounts, and then up to the radiator and reservoir. I'll have the pump wired in so it's always on with the ignition like the Tundra's supercharger is setup.

 

[snivilous]

Now onto the meat! I did that while waiting for the parts to show up from East Coast Gear Supply. I have never regeared or really messed with differentials at all, let alone one ton stuff so jumped in feet first. This always seemed complicated, but like most things after figuring it out and doing it it's actually pretty simple. I also had two friends (RPS1030 being one) come over and help me over a weekend which was great! A lot of stuff was done, all the axle seals, the lock outs, ball joints, unit bearings, rear axle bearings, front axle shafts, axle seals, differentials, gears, I think the only thing that wasn't replaced was the rear axle shafts...

I went with 5.13 gears, this seemed like a good middle ground between 5.38s and 4.88s. I've seen some videos of people with similar drivetrain setups and 4.88s and they seemed to have plenty of torque plus the strength of 4.88s, but I was hesitant due to the 4l80e having a fairly high 1st gear and the Atlas only being 3:1 and since this will be more of a high speed crawler than a racecar that can crawl so 5.38s was appealing too. The rear is a straight up spool, my last racecar had a spool and I like the simplicity of them. The front is a Yukon Grizzly auto locker. The unit bearings are from Branik. The lock outs are from TMR. The RCVs are 35 spline. The rear shafts as I said are the stock 35 spline ones until I hurt one.

Fast forward about a week and finally got everything buttoned up and took it on it's first test drive! And within about 700ft the front end completely locked up. Luckily I had driven around the corner, turned around, and then it locked up so didn't make it very far from the shop. Pulled the lock outs so the front axles weren't engaged and drove it home.

The front rear pinion bearing had gotten utterly cooked, ate the cage, and seemed to have welded itself to the pinion.

There was no signs of lubrication whatsoever on the bearing. That combined with running the preload on the higher side is what did it in. The pinion angle is fairly high, I want to say like 17deg, and I had used the stock fill hole on the diff cover. Additionally, I hadn't installed the oil slinger for the pinion due to the OEM pinion not having one, so that bearing never saw a drop of oil. I tried a few different methods to remove it, beating the shit out of it with a sledge, tried melting it with the plasma, tried pressing it out with this contraption I welded around the axle...

Ultimately I dropped it off at a machine shop, though I first cut the steering skid off in the hopes a shop could fit it on their mill.

Which it ended up I didn't need to do, since the shop was able to use a torch to melt the pinion out! Might be time to buy an oxyacetylene setup myself... But for $40 I went from pricing out Spider 9s and thinking the housing was time for scrap to having it saved!

I called up East Coast Gear Supply and again hoping to buy just a pinion, which they said they couldn't do and it'd have to be an entire gear set which I kind of figured. So I bought another set of front gears, and they were able to get me just the pinion shims since I still had all the parts from the rebuild. I really have to thank ECGS, I had told the guy why I wanted just the pinion and then he had given me some advice which was awesome, and then dude said he'd give me a discount to help with stuff. I thought that was super cool, but I wasn't trying to save money, they had just been super helpful the first time so that's why I was going through them again. I figured dude was giving me like 5-10% off like most places have coupon codes for. When I got the invoice though the guy had given me a huge discount, and essentially made it so I only had to pay for the new pinion! I thought that was one of, if not the coolest thing a company has ever done. I couldn't care less if I had saved money and I'm just a random guy that was a moron and seized his diff on the first drive, and this guy at ECGS comes out swinging and doing everything possible to help me. I think that is extremely cool, dude had no need to do that and I would've recommended them regardless. So huge thanks to ECGS, you had earned my business from the first order, let alone the second order, and then to top it off with that is just so cool!

Anyways, I now got to weld the steering skid back on! So this poor thing is already seeing some scars and I don't think it's run into a rock yet!

I also bought some of the Spidertrax big fill plugs and welded that to the top of the housing so I can fill it as much as I want easily and have a view of the gears.

I only used the pinion from the new gear set. I couldn't find a definitive answer if the gears are matched to each other from the factory. I was able to get an acceptable pattern without touching the shims on the differential, which is why I didn't want to swap in the "new new" ring gear in case that threw the diff off. I figure worst case, it's an offroad vehicle, if there's some extra gear noise who cares. At this point I just want this axle behind me. I also opted to NOT install the pinion oil slinger and baffle, which afterwards I had some conversations and did some research since I was worried about that decision. In retrospect it wouldn't hurt to have installed those. But from my research it's a 50/50 call from people whether to install those. Some say for offroad they're not needed, some say for onroad they are needed, some say if they didn't come on the OEM don't use them (the advice I had followed). What I did do though is I installed everything and left the pinion seal OFF and ran the axles on the lift so I could make sure the rear bearing was getting lubed. I put in a LOT of gear oil, essentially the pinion gear is half submerged in oil, but what that means is the rear bearing is constantly in a gear oil bath.

Anyways, putting the front end back together. I also overfilled the rear by an extra couple quarts to be safe there, though there was no indication the rear was having issues.

And that wraps up last week! And then in the past few days I've done a few small things. First up was the front driveshaft is kind of a cluster, and ultimately was not able to droop enough without binding. So I pulled the yokes on the chassis side and machined them to clear more and now the driveshaft can fully droop without binding up. I'm not a fan of my driveshaft setup, I might revise it in the future but for now this will work. I also have a midship section (so small driveshaft off the Atlas to effectively a second mini driveshaft mounted on bearings in the chassis, which then goes to the actual front driveshaft to the axle) and I didn't know if I had remembered to lubricate that years ago when I installed it, so I drilled and tapped a fill hole into the midship housing (the housing that's welded into the chassis which then holds two angular contact bearings and then the shaft and two flanges), so the midship bearings are now actively lubricated in gear oil also. Though I actually had to pull the midship to machine the yoke, and found out I HAD lubricated the bearings with grease, so there's now a lovely grease/oil slurry for those two bearings!

I also threw the V-bands onto the header and exhaust instead of them being tacked together. I also bought some additional O2 sensor bungs so moved the wideband sensor to a better spot that wasn't poking through the floor.

And that all leads to yesterday where I went on the first successful 4WD drive! And I was extremely cautious about measuring the temperature of the housings at the pinion bearings to make sure I wasn't cooking them and so far everything was behaving as expected!

This thing is god awfully slow still. It was horribly slow before, and it's still so slow I don't even notice/remember a difference from the 3.73 gears it had. It might be time to build the 408 stroker motor sooner rather than later... but it runs and drives again! Plus a bunch of other little upgrades! Maybe take it to Sand Hollow this weekend and finally get it in the rocks. The next thing I want to do is build a proper fan shroud for the two radiator fans, I think that will be the next project.

 

[chaplinfj60]

fuckig bummer on front pinion. glad its doing well now .. rock on

 

[SMI17]

Sucks to deal with all that crap. Only comment I have sometimes over filled diffs will puke more fluid when warmed up or maybe leak at the axle seals. Maybe a bigger catch can for the vents. I overfill my diffs by a qt or so due to pinions tilted up some. But if it really hurts or not is ultimately down to luck and chance. 🤷‍♂️

 

[snivilous]

Sucks to deal with all that crap. Only comment I have sometimes over filled diffs will puke more fluid when warmed up or maybe leak at the axle seals. Maybe a bigger catch can for the vents. I overfill my diffs by a qt or so due to pinions tilted up some. But if it really hurts or not is ultimately down to luck and chance. 🤷‍♂️

Good to know! The guy at ECGS said a similar thing.

The night after I filled the front diff it leaked a bunch out the driver's axle, but then seemed to stop for some reason even though I'm pretty sure that seal is still completely submerged... We'll see what happens and cross that bridge if we get there. After driving it around the block yesterday somehow nothing is leaking so fingers crossed the axle shaft fixed itself and then just the breather to maybe deal with.

 

[Bebop]

I'm gonna say it, because it bothers me. Feel free to tell me to shut up.
But most of the issues you're dealing with could have been solved / prevented with minimal research.

Plenty of people willing to help you do it right on this board, and I know you know plenty of people IRL ready to help.

I don't understand this mentality:

I only used the pinion from the new gear set. I couldn't find a definitive answer if the gears are matched to each other from the factory. I was able to get an acceptable pattern without touching the shims on the differential, which is why I didn't want to swap in the "new new" ring gear in case that threw the diff off. I figure worst case, it's an offroad vehicle, if there's some extra gear noise who cares.

Anyway, good on you for keeping on trucking. I hope the rest of the car does well.

 

[snivilous]

Next up is the radiator fans! My plan from the start was to use two Ford Taurus fans (which for anyone who doesn't know flow a ton of air, cost under $100, and have two fan speeds). I have run a single Taurus fans on my previous racecar and a single fan on my 2JZ Hilux, though both of those involved using the fan shroud that comes with the fan (in the case of the Hilux I specifically sized the radiator to fit that shroud). But a single fan wasn't gonna comfortably fit my radiator this time, and two stock fan shrouds were way too big, so a couple days ago I started building my first radiator fan assembly!

Sadly my plasma table was like two inches too short to cut everything in one pass so it's essentially two single fan units mirrored around the center.

I haven't used the Tig a lot lately and got in a lot of practice with aluminum on this project! Aluminum may be my favorite material to weld, it flows so nicely and is so pretty. Now I'm not a welder by any stretch but I'm super happy how this turned out!

Now the "tricky" part was mounting the motor, which I had an idea for some little arms to come out radially to each corner to have a good load path, but I was worried since the fan unit by itself is 5lbs that some flat sheet wouldn't work well, so I made these boxed in arms and they're cut from a single piece, folded, then welded.

All 8 arms (four per motor) welded and ready to rock.

Next up was completing the shroud profile. The edges of the radiator sit a little higher than the actual core, so the shroud steps down in the middle section to create a good deal around the core, as well as help locate it.

You can also see I ended up cutting off the bottom right corner to clear where I have some fuel lines. You might also be able to tell the fan shroud is WAY bigger than the radiator. This is obviously a side effect of how huge the fans are. So to make sure the core got the full flow, I added some panels on the back side to narrow the shroud so the backside air inlet only aligns with the core.

Now you may be saying that seems like a lot of space blocked off, why not run a single fan? Well my thought is one of the OEM fan shrouds was maybe 6" narrower than the radiator core, so I would've been adding a lot more area than the stock fan is responsible for. Additionally this gives some degree of redundancy and controlling how much cooling power I need. And lastly I have two banks of additional radiators under the main radiator, so now there is a fan directly inline with each of those sub system radiators, which in my mind means each side will get plenty of cooling.

Anyways, back to building the shroud. Today it was time to mount the motors, and the huge boxy arms just weren't clicking for me and didn't turn out as cool as I envisioned. So I did a napkin stiffness calculation of the OEM shrouds support arms and checked it against some simple plate arms and of course some simple plates are orders of magnitude stiffer than the OEM arms, so I scraped the boxed arms and went with some simple plate ones which give a much better aesthetic, are much simpler, and weigh a lot less.

As far as mounting the shroud to the radiator, I wanted something modular and did not want to weld to the shroud. The current radiator is a little funky, so if I change radiators or want to move this shroud to something else I wanted to avoid as many changes as possible. What I ended up doing was making some super simple brackets that just grab the edge of the core and bolt to the shroud. The bottom has four of these little fingers, and the top side has two and the two on the top side as they bolt down also vertically clamp the shroud. The bottom fingers line up with the radiator mount itself and kind of index into it so the bottom of the shroud is laterally constrained--and then of course the shroud itself is also indexed to the core with the little step downs I mentioned above.

And the final result is absolutely gorgeous I think! Definitely a contender for nicest thing on the buggy!

I need to wire in the second fan, and a few other items and then I think it'll be ready for some trails!

 

[1Sinner]

That's rad

 

[I Lean]

That fan shroud and all is awesome...and since you already did it, this will only make you mad. But maybe it will help you in the future, or someone else. What you did will work perfectly, it was just more work than another option:

Certain Volvo fans are essentially the same as a Taurus, but are in a nice flat stand-alone housing, ready to mount to a flat surface. They unbolt from the bigger rectangle shroud easily (if you're sourcing from a junkyard), and have the cool relay units with them already.

They look like this:

 

[snivilous]

That fan shroud and all is awesome...and since you already did it, this will only make you mad. But maybe it will help you in the future, or someone else. What you did will work perfectly, it was just more work than another option:

Certain Volvo fans are essentially the same as a Taurus, but are in a nice flat stand-alone housing, ready to mount to a flat surface. They unbolt from the bigger rectangle shroud easily (if you're sourcing from a junkyard), and have the cool relay units with them already.

They look like this:

Hahaha that would've simplified life a bit! I will definitely try one of those next time!

 

[arse_sidewards]

I have one of those “in inventory”. Iirc it came off a late 90s or early 2000s era Volvo.

 

[Pyleit]

Hit me up when you want to go to sand hollow for a test run and ill meet you over there.

 

[snivilous]

Hit me up when you want to go to sand hollow for a test run and ill meet you over there.

That'd be great, I'll send you a message! RPS1030 is the only local person I know with anything more than a UTV, let alone willing to go into the rocks

 

[RPS1030]

Shakedown at 3 Peaks

 

[chaplinfj60]

That'd be great, I'll send you a message! RPS1030 is the only local person I know with anything more than a UTV, let alone willing to go into the rocks

holly crap, your in the mecca of off roading and have a hard time finding people. hahahaha thats crazy...

 

[chaplinfj60]

by the way i love the shroud too. diff thinking out side the ox to solve the issue.

 

[snivilous]

holly crap, your in the mecca of off roading and have a hard time finding people. hahahaha thats crazy...

It's not like I actively go up to everyone I see and asking them out, before yesterday I was just another dweeb with a UTV

 

[chaplinfj60]

hahahah fair enough. lol

 

[snivilous]

Took the buggy out yesterday after wiring in the radiator fans and intercooler pump, and also added some more interior panels behind the seats to act as blast deflectors if the radiator or cooling lines gave up (previous times you'll see a welding blanket draped behind the seats because of the lack of those panels). Only got one photo (reference RPS1030 photos above for more).

With the exception of the battery terminals deciding they didn't want to be battery terminals when this photo was taken, everything else worked great! Did a couple miles on dirt, tested out high and low range, did some crawling. Temperatures were all good and everything seemed to function correctly!

I opened up all the rebound tubes on the bypasses which were previously at some random position. That certainly bumped the body roll a noticeable amount but it's still well within the comfortable zone and still without a sway bar. The front suspension seems to move and behave fine and how I would expect, I think it should be straight forward to get dialed in. The rear still has the weird side to side shimmy on small bumps. I'm going to check how square to the chassis the axle is, I'm hoping it's something as simple as the axle being out of alignment. I would be surprised if it's a shock tuning issue, since it's not like it's chattering around due to washboard but seems to kick the rear to the side on just normal bumps so seems to be a geometry issue. I would also be surprised if it's a link setup issue, when I've flexed the rear out on the lift there seemed to be minimal rear steer, let alone from the axle moving just a couple inches... Anyways, the rear axle handling on the small bumps is probably the biggest setup/tuning issue to address. EDIT: Well I just ran out to it with a tape measure and at a minimum the passenger front upper ball joint is a full inch further from the rear axle than the drivers side. Maybe it's even the front axle is out of alignment with the chassis and just feels like the rear since it hits everything second. So first up will be getting all the suspension properly squared up!

The steering and supercharger cooler seems to work great, though the radiator for it is not getting enough airflow. There's a good size gap between all the radiators in the stack so you can feel that air isn't being forced through it. I'm going to box in the sub system radiators and seal them against the main radiator to force more air through them. Though the cooling loop seems to work in principle at least. I do wish the steering was a lot faster, I have a 3 turn orbital and would definitely like a 2 turn. I'd also like to swap out the 8" ram I have for ideally like a 9" ram so I can use all of the steering from the RCVs. Though Howe who all the steering is from doesn't have a 9" ram, and I'm not sure if other companies have the same mounting setup to easily swap rams. The flip side is I could run a 10" ram from Howe and just rely on the axle stops? Or maybe the 10" can be easily converted internally to a 9"? The turning radius is kind or terrible since the thing is 119" wheel base and only steers as far as a stock F350.

The power with the gearing is a bit better than it felt the other day. It's still pretty gutless, but seems to pick up a bit in the mid range. The trans is also a completely stock 4L80e, for that matter I don't even remember where it came from... so it's probably pretty worn out. Certainly crawling it seemed like it had it's moments where it'd decide to dump power into the axles somewhat randomly instead of easily creeping up on the power. With that said, the crawl ratio is more speed oriented obviously with only a 3:1 in the Atlas. It seemed to crawl fine, and did everything I wanted from it. Only having Toyotas prior to this I'm used to a crawl ratio in the 30-40 range so no complaints. Though on the note of the trans I could never feel it shift. It definitely would, and the Holley said it was, but that seemed kind of odd to me. Going down a steep hill with it in 1st, it was definitely engine braking and then shifting forward it would go faster, but I could never FEEL it shift. Again, completely stock trans that's who knows how worn out so maybe that's normal? And to be fair I never did a full throttle from a stop and let it run through the gears as hard and fast as possible, but I still expected something a bit more violent instead of CVT feeling performance... It seemed to work fine though! Also there is no trans temperature, so need to figure out how to add that into the Holley or an external gauge.

The main radiator seems to be working fine, though the engine is getting hotter than I want. It hit 205ish at the hottest, and to be fair I don't know what thermostat is in it anymore (great thing about taking years to get something going!). I think the issue is due to the extreme radiator angle of it being mounted on the C pillar, is the top of the radiator physically cannot be filled with coolant so there is inherently a huge air bubble at the top of the radiator constantly. I'm thinking I will add another fill spot on the true top of the radiator to fully fill it so it can properly pressurize then. I think that will fix how hot it's getting, since running over 200 with both fans on full blast and just running around some normal trails isn't gonna cut it when it's in the desert on a hot day actually making some power.

I think that covers most of my mental notes. As usual, lots to keep adding to it, but it feels like a real trail rig now! I'm looking forward to putting some miles on it and tuning and tweaking and dialing it in and learning what it likes.