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

Old HDT’s are cheap for a reason. You’re probably in the neighborhood of 50 cents per mile in maintenance costs at that age and presumably around 700-800k on the clock. Volvo support/parts can be tough to come by. They find ways to hurt you that you’d never even imagined before. On top of the cost per mile, you’re a dropped cylinder liner or a wiped cam away from being faced with a $25k inframe or it being worth scrap. Which is not an uncommon occurrence unfortunately.

That being said, I’m here for it. Assuming you’ll strip the 5th wheel off and build a flatbed for the back?
Completely agree, and we'll see how it holds up. The chassis has 1.8M on it, engine was rebuilt 400k ago, tranny seems fairly fresh my neighbor thought. My hope is I won't drive it enough and it'll have no load on it so it'll survive what I need. Maybe that's a wet dream, but if I have to leave it on the side of the road it's in the realm of being a bearable loss. I don't want that to happen, but it'll be somewhat of an experiment :grinpimp:

And yes sir, that's the current plan. Strip the 5th wheel and flatbed. I took it for a spin a few times, registered it, and parked it and focused on KOH rebuild so far. Will start working on it pretty soon now that one project is somewhat sorted.
 
Completely agree, and we'll see how it holds up. The chassis has 1.8M on it, engine was rebuilt 400k ago, tranny seems fairly fresh my neighbor thought. My hope is I won't drive it enough and it'll have no load on it so it'll survive what I need. Maybe that's a wet dream, but if I have to leave it on the side of the road it's in the realm of being a bearable loss. I don't want that to happen, but it'll be somewhat of an experiment :grinpimp:

And yes sir, that's the current plan. Strip the 5th wheel and flatbed. I took it for a spin a few times, registered it, and parked it and focused on KOH rebuild so far. Will start working on it pretty soon now that one project is somewhat sorted.

Definitely an experiment with 1.8m on a Volvo chassis :grinpimp:

You’ve got an EGR only emissions truck so that will help with some costs for sure compared to an 08+ with alphabet soup emissions. I’d just be ready with $10k set aside that you have no emotional attachment to for repairs/maintenance.

They drive easy and have great power compared to an MDT that is kind of miserable on a long drive when they can’t even hold 70 on a small grade empty. You shouldn’t even notice the buggy on the back in the hills with HDT power. D12 and a 10 speed?
 
Definitely an experiment with 1.8m on a Volvo chassis :grinpimp:

You’ve got an EGR only emissions truck so that will help with some costs for sure compared to an 08+ with alphabet soup emissions. I’d just be ready with $10k set aside that you have no emotional attachment to for repairs/maintenance.

They drive easy and have great power compared to an MDT that is kind of miserable on a long drive when they can’t even hold 70 on a small grade empty. You shouldn’t even notice the buggy on the back in the hills with HDT power. D12 and a 10 speed?
You definitely know way more than I do :grinpimp::lmao: I think it's a D12, but I wouldn't know the differences. And yes 10 speed Eaton. It's a 2005.
 
Where did you pick it up in Boise? From a dealer or individual? I am local to Boise and want a semi one day :grinpimp:
 
Where did you pick it up in Boise? From a dealer or individual? I am local to Boise and want a semi one day :grinpimp:
Dude actually picked us up from the airport and had the truck waiting at the truck stop the next exit down so we were in and out in an hour and a half. I found it on KSL :grinpimp: there was a NASCAR race trailer and truck setup I was gonna look at near Kanab UT that I thought was a good deal (again, comparing to toters and the like) and then found this pile for way cheaper and jumped on it hahaha
 
You definitely know way more than I do :grinpimp::lmao: I think it's a D12, but I wouldn't know the differences. And yes 10 speed Eaton. It's a 2005.

I worked for Dayton Freight as a manager for almost 10 years and own my own small fleet now so I've definitely had some exposure to trucks for better or worse. Holler if you ever need a sanity check on something with it.

My most recent project was stretching a Prostar from a daycab truck into a straight truck so we got some practice on cobbling stuff together for our specific use case :dustin:


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Got anything new on the buggy?
Was waiting to post until next week since I'm planning to go to sand hollow this weekend. I've done a couple things since KOH. First was moving the tie rod to the inner hole which increased my steering angle from 30deg to 42deg

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The ram isn't quite maxed out but I had to trim so much shit, and the RCVs max at 45deg so it works out. I can't steer further without hitting the shock. Nearly a 50% increase in steering plus will speed up the steering ratio, though I still want to go to a 2 turn orbital.

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Can't wait to try it out in the rocks! It's a considerable difference driving around normally.

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And then the recent thing was I found cylinder 4 wasn't firing, as well as the blower was only making 2psi and the bypass valve wasn't fully closing. I think I found the issue being a plug wire that was cracked and shorting out. I replaced that coil pack and the plugs also, and changed the oil. The oil looked great, normal super fine metal shavings and no large chunks so the engine seems happy! I bumped to 10w-40 since the oil pressure seemed a bit low and that's a common thickness to run. I also welded a new filler cap on the radiator that's oriented (more) vertically since the previous cap was next to useless for filling it with how angled the radiator is. I also temporarily zip tied the bypass valve closed to test what max boost with the new engine setup is. I then started running into issues the past two days of the serpentine belt eating itself even though nothing seemed to change. I ended up welding a flange on the back side of the tensioner pulley since the serpentine was falling off the back side for some reason, and then next tracked down that one of the idlers wasn't in plane with the other pulleys so was pushing the belt slowly off of the power steering pulley. I have no idea why all of this started having issues, it was fine at koh and then I pull the belt off and reinstall it and then everything got hacked up somehow. I think I'll scan the front end and design some billet mounts for everything in the near future, I've wanted to do that for awhile since the belt routing and mounting can be improved.

With all of that said, last night was the first successful test drive since getting it running on all 8 and having boost and the serpentine surviving!

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And holy shit it pulls like a mule now. Running as a N/A V7 it already made the 5.3 feel slow, but this feels like almost a double in power with it properly running. It pushes you back into the seat launching in 4wd pretty good, and that's only at 8psi from the blower and still with that original tune done at just idle and blipping the throttle. My Tundra does 0-60 in sub 5s and this feels not quite that fast but not far off. I'm really happy with how it feels now, and the engine is running great. This is also through the same worn out old 4l80e and torque converter. New trans and converter and maybe a smaller pulley and it has a lot of power left on the table. I'm also only spinning it to 6k, so theoretically it's just chilling and not working very hard.

Oh I also added a proper catch can!

Can't wait to see how it does this weekend, maybe do another test drive tonight to make sure the serpentine is fixed and also hook the bypass valve back up and get it adjusted, otherwise the semi needs a bit more work on the deck and then will do the first trip with the semi+buggy combo!
 
nice job on the repairs. I'll be following to hear how those knuckles work out long term.
 
Getting the boost back and the extra cylinder is probably where your belt issues arose from. You have both more pull and drag on the belt system now. Any flex, misalignment, whatever, got magnified.
 
Good trip to Sand Hollow with the new setup!

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Didn't really get any photos, and stole some from RPS1030 of Pyleit and I.

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Buggy is working great. The new steering angle made a huge difference, I would've been backing up all over before.

I'm thinking I might need to put a larger alternator in, we stopped at one point and I turned the engine off and just a few minutes of the fans and fuel pump running killed the battery (though it self recovered).

The new engine seemed a bit more tame for crawling than at KOH, not sure why. Maybe just the different rocks. The thing is so brutally loud, I might change the exhaust or try to add more mufflers. I can feel my ear drums shake even without full throttle if I don't have a headset on, and I can live with it being loud but when you're trying to crawl or idle and can't hear anyone talk it's a bit much. We were talking about having the exhaust exit up and over the vehicle instead of dumping in front of the axle might help too, thats obviously how a lot of Ultra4 setups are and a lot of them run the same mufflers I do.


The carrier bearing had some issues coming loose, got it tightened up temporarily and then dropped the front driveshaft off at Driveline Tech just down the street. He's building me a new front driveshaft and I'll drop the rear off to get copied soon too. There's a race end of April and the front was thrown together for KOH and needs to be proper to go fast.


I did a quick sprint through the West Rim loop at the end, the buggy is all around doing awesome. Shocks need some more tuning but it's handling great, has tons of power, and does alright rock crawling so I'm very happy how it's working. Turning into a really fun dual sport setup!
 
Threw some GoPro mounts on the chassis and spent a few hours fucking around.



I need to pull the plugs again and see how it's looking, it feels fine but one of the exhausts sounded a bit weird. I ordered a second wideband, but the Holley somehow doesn't have misfire detection which blows my mind, so besides monitoring left vs right AFR and how the engine sounds there's no easy way to know if it's firing on all 8 (I've used a IR gun but that's not very reliable since the rear header tubes are hard to get a good reading off of). I should probably buy ANOTHER set of plug wires and swap them all out to be safe, course for all I know it's running on all 8 fine... It certainly feels fine, but I thought it felt fine when it was only running on 7 too so now I'm worried.

Still waiting on the new front driveshaft. Talked to Tyler @ ADS a bit more (not about the video, just in general) and he gave me some valving recommendations and sent me some .020" shim packs.

Despite all that, what an absolute blast it is to drive around. Without the front driveshaft vibrating away it's so smooth, flooring it and accelerating past 70 still seems surreal to me, this big lumbering crazy vehicle I built actually being able to do that. I'll probably look back in 5 or 10 years and go wow that thing handled horribly, but right now I'm enjoying it and loving it! Hopefully get the shocks revalved in a week or two, go down to Sand Hollow and throw the GoPro on it to get some footage in the whoops and do some shock tuning before the race in Vernal.
 
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