: rockbuggy, and H1/HMMVV suspension


Guinness44
03-03-2008, 01:45 PM
The Chile Challenge made me curious. Lots of diffs hanging on the rocks. Buggies are as big from corner to corner as the H1/HMMVV anymore. The friendly branddickering with one of my pretty extreme rockbuddies, makes me wonder WHY not independent suspension. We used to drive the lifted TJ, and dare not to have air under a tire, so now we have air under a tire immediately, and keep going. I guess one would need some serious rocksliders, and certainly remove most of the body (like some MOGs I saw). Anyone done/doing this?

Kustom Fabrikated
03-03-2008, 08:54 PM
Here are links to 3 threads discussing the same idea, hope they help.

http://pirate4x4.com/forum/showthread.php?t=602597

http://www.race-dezert.com/forum/showthread.php?t=32276

http://nc4x4.com/forums/showthread.php?t=34456

Guinness44
03-04-2008, 09:43 AM
Thanks for links, interesting. Would never chop my truck anyway. But was wondering why the crawling buggy people are so much into this solid axle thing. I was definitely thinking to use geared hubs, thats what makes the Hummer so capable. If a fully (over)loaded H1 makes it up Hells Gate (over 12000 lbs), how would such a truck perform stripped to basics (like the MOG was).......

93hummer
03-23-2008, 07:43 PM
http://www.arcticoffroad.com/forum/gallery/files/1/0/0/2/6b_1.jpg

http://www.arcticoffroad.com/forum/gallery/files/1/0/0/2/87_1h.jpg

http://www.arcticoffroad.com/forum/gallery/files/1/0/0/2/8b_1.jpg

These are pics from an Ebay crawler sale about a year ago, I don't know who bought/sold it, I just thought it was cool and showed that a Hummer IFS portal setup could be made to flex. The Hummers are just WAY too oversprung, but with the right setup, it could be made to flex more.

tacoma73
03-23-2008, 08:10 PM
]

These are pics from an Ebay crawler sale about a year ago, I don't know who bought/sold it, I just thought it was cool and showed that a Hummer IFS portal setup could be made to flex. The Hummers are just WAY too oversprung, but with the right setup, it could be made to flex more.

....except that what you are looking at is NOT an IFS setup, it's IFS parts in a solid axle cradle deal. Notice the lack of pivots, and look at the pic of the front end flexed on that rock.


Walker Evans tried IFS for crawling, and he's not doing it anymore. Why not? :D Solid axles lift the vehicle away from obstacles when one end goes up, IFS just sucks up into the body, and doesn't help w/clearance.

Not saying it can't be done, just that it isn't.

93hummer
03-23-2008, 08:21 PM
Dang, you are right, I saved those pics over a year ago and hadn't seen that until you said it.

Rock Ape
03-23-2008, 11:02 PM
....except that what you are looking at is NOT an IFS setup, it's IFS parts in a solid axle cradle deal. Notice the lack of pivots, and look at the pic of the front end flexed on that rock.


Walker Evans tried IFS for crawling, and he's not doing it anymore. Why not? :D Solid axles lift the vehicle away from obstacles when one end goes up, IFS just sucks up into the body, and doesn't help w/clearance.

Not saying it can't be done, just that it isn't.

Im pretty sure he junked the idea because the steering was pretty hard to keep the front wheels steering in sync....I happened to see it at the last crawling event they ever had at the moonrocks....it stuck like a spyder...and when they jacked it up to work on it there was 30" inches under the center section just to get the rear tires off the ground!!!

I think a ifs rig is probably do-able but some serious thought and engineering as well as $$$ would need to be invested(the walker buggy had all those things but in my opinion got junked before they were worked out!!!).

heres a few pics..
http://www.4wheeloffroad.com/brandpages/chevy/131_0306_evan_walker_chevrolet_s10/index.html

stjames151
05-11-2008, 11:11 PM
HMMM! I just got an idea! If you did a suspension kit like this, would it be possible to engineer a hydraulic wheel leveler that keeps the wheels parallel to the body. This would maintain most of the on-road characteristics that make IFS so attractive, while still giving you the flex of a solid axle rig, or is it just too complicated? In theory it seems pretty simple. Couple of rams, some "an" fittings, and a bit of steel braided hose connected to the shocks pushing/pulling the portal upper connections in/out....IT COULD BE DONE!!! or can it?

caseyray63
05-12-2008, 01:32 AM
Mabye I'm missing the point but if you ran an airbag suspention with a cross over line from side to side wouldn't it act like a solid axle? When one tire goes up the other goes down keeping the tires on the ground. Solid axle caricteristics with independent clearance. And you would be able to raise and lower the vehicle for clearance as needed.

ron b
05-12-2008, 10:50 AM
Mabye I'm missing the point but if you ran an airbag suspention with a cross over line from side to side wouldn't it act like a solid axle? When one tire goes up the other goes down keeping the tires on the ground. Solid axle caricteristics with independent clearance. And you would be able to raise and lower the vehicle for clearance as needed.

This is true and I know two guys who did this (me being one of them). It's dangerous on the road, but cool on the trails. You still have the lack of travel issues, but that can be slightly improved by limit straps, longer shocks and balljoint mods. My bags are now independantly controlled for safety/convenience, but if it was purely a trail truck...

rb

RedBullJeep
05-12-2008, 04:20 PM
Independant doesn't climb the same, break-over, or turn and climb nearly the same as straight axle. Nobody has made it work in numerous attempts, even the "father" of long-travel desert race suspension, Walker Evans.

Steering was a small issue he was having...a big drop in big obstacle performance was the main reason.

fullsizetoy
05-13-2008, 03:54 PM
This rig was built by a guy named Dane on this board he is from Elk Grove, CA. It performed very well as I remember. I was in the bypass years ago at the Con with him. Other than a busted coolant hose he was pretty happy as I recall.

Tom


http://www.arcticoffroad.com/forum/gallery/files/1/0/0/2/6b_1.jpg

http://www.arcticoffroad.com/forum/gallery/files/1/0/0/2/87_1h.jpg

http://www.arcticoffroad.com/forum/gallery/files/1/0/0/2/8b_1.jpg

These are pics from an Ebay crawler sale about a year ago, I don't know who bought/sold it, I just thought it was cool and showed that a Hummer IFS portal setup could be made to flex. The Hummers are just WAY too oversprung, but with the right setup, it could be made to flex more.

Brianholbrook
05-31-2008, 04:09 PM
Actually my name is Brian-- Tom, long time no talky! . I wish I never sold that crawler. Does anybody know where it is? Anybody that seriously wants to know how I did it can emial me Bholbrook@landsberg.com and I would like to help somebody do it again. Those axles worked so well I can't believe knowbody has done what I did with those axles.

ron b
05-31-2008, 06:55 PM
Actually my name is Brian-- Tom, long time no talky! . I wish I never sold that crawler. Does anybody know where it is? Anybody that seriously wants to know how I did it can emial me Bholbrook@landsberg.com and I would like to help somebody do it again. Those axles worked so well I can't believe knowbody has done what I did with those axles.

really cool crawler -- any more pics?

Jeep07
06-01-2008, 10:13 PM
I would love to see more pics of this setup.

fullsizetoy
06-02-2008, 01:28 PM
Actually my name is Brian-- Tom, long time no talky! . I wish I never sold that crawler. Does anybody know where it is? Anybody that seriously wants to know how I did it can emial me Bholbrook@landsberg.com and I would like to help somebody do it again. Those axles worked so well I can't believe knowbody has done what I did with those axles.


Brian,
Hey whats us. I was actually talking to my buddy Dane when I was typing and wrote his name instead of yours. My fingers were working faster than my brain.

anyways it was a sweet rig and I would have loved to have it. Hows the new project coming. Is it a driver yet?

Tom

Tech Tim
06-02-2008, 06:59 PM
I would love to see more experimenting with long travel IFS for Rock Crawlers. Everybody knows Walker had a hell of a time with it, but he also didn't run it very long and I would agree that the arm set-up he was running was part of the issues he was having.

ANd let's not leave out Randy Ellis' Red Racer. IFS and IRS and he did OK in a few of the rock crawl events he ran it in.

It was being discussed on Racedezert awhile back and one of the guys was implying that using the Hummer portal with IFS would reverse the lifting effect and help IFS bite more. Not sure why, but something to look into.

We got a chance to run a Total Chaos long travel equipped FJ Cruiser around the Hammers at the KOH and we were impressed as hell with it. It only had 32s on it so we were doing extremely mild stuff with it (read that no hard core trails), but it climbed up and over the rocks that were in our way and some of them we thought no way. We had more issues with hanging the under body up on stuff than we did with the front end hooking up. Big heavy rig + little tires= bellying most stuff.

I would like to see that suspension under a small lightweight buggy with 37s..... hmmm, maybe that's what we'll build for the KOH '09... :laughing:. That is if we can get an invite. The biggest issue will be coming up with some CV assemblies to handle the load.

Brianholbrook
06-05-2008, 08:44 AM
Hey Tom, it's not a driver yet but will be in a few months. It has an H1 body with Cummins 12 valve, Klunvee, Unimog 416 (front/rear steer) 50" Michelins, large air bags. Can't wait to go on the Rubicon soon with it. In fact, I mis being there so bad that I am taking my Cub Scout Den there this weekend. We are going to hike the Rubicon!

Brian

Bebe
06-05-2008, 12:47 PM
Hey Tom, it's not a driver yet but will be in a few months. It has an H1 body with Cummins 12 valve, Klunvee, Unimog 416 (front/rear steer) 50" Michelins, large air bags. Can't wait to go on the Rubicon soon with it. In fact, I mis being there so bad that I am taking my Cub Scout Den there this weekend. We are going to hike the Rubicon!

Brian


That sounds like fun !!