unccpathfinder Posted April 15, 2008 Share Posted April 15, 2008 So about 2 or 3 months ago I was sleeping...dreaming of building up the pathy some more and hitting the trails...so I started thinking that all the body lifts use some sort of hard spacer block which got me to thinking about welding "lift blocks" to the frame...My rational behind this is in with the body lift bolts you leave the realm of bolt shear and get into bolt bending so if there was structure welded to the frame with either the stud prewelded into the box for the nut on the inside of the cab or vice versa...the alternative to this would be to have about a 1" hole along somewhere on the closeout box that would allow you to insert a wrench to install a nut... So I think with this you could go with a 4-5"BL to squeeze bigger tires under while maintaining more integrity in the joint between the body and frame...granted this is going to make the roll over moment of the whole truck a lil more extreme but the pathy seems to have a pretty good stance and I think < 6" BL with < 6" SL it would still be pretty manageable onroad Opinions/suggestions welcomed Anyone know of anyone at nissan that could provide me with design/proof loads...i htink thats a fat chance but figured i'd throw it out there... Link to comment Share on other sites More sharing options...
packie88 Posted April 15, 2008 Share Posted April 15, 2008 i think you would need both sway bars no matter what. and i know in some states bl cant be greater than 3 inch. anything mor ethen 3 inch and i would be you would flip it. as it is 3 inch provides a ton of body roll. more than you think. you idea might work but i would only go with 3 inch or less Link to comment Share on other sites More sharing options...
Simon Posted April 15, 2008 Share Posted April 15, 2008 (edited) Body lifts keep the COG a little lower than the same amount of suspension lift. The frame, engine, and suspension components (heavy stuff)stay at the same height. That said, I don't believe I'd go ANY more than a total of 6" of lift, without going wider. I've got a 3+3, and my tires stick out quite a bit, which makes for an almost stock ride/stability. However, any taller, and I'd be looking at wider axles, or at least rims with less backspacing. The engineering it would take to make your idea a reality just isn't worth it. for under $100 you can get 3" of lift. Can't think of a much better bang for your buck! Edited April 15, 2008 by Simon Link to comment Share on other sites More sharing options...
unccpathfinder Posted April 15, 2008 Author Share Posted April 15, 2008 (edited) The engineering it would take to make your idea a reality just isn't worth it. Well that is my day job so for me it's just a matter of finding the time, figuring out the design loads nissan used under what conditions, Locating the stock CG which I'm going to make a guess is right about where the handbrake is maybe a little FWD and inspect how they transfer loads to and from the body Last night I thought I would also have to create electrical extensions for things like the fuel tank sending unit but maybe not along with bumper and radiator relocation brkts.. that said even a 3" kit I think would be safer that either welds to the frame or uses 3 or 4 steel bushing you drill and press into the frame run the bolts through and attach the steel box on top with shorter fastening bolts from the "frame" to the body in the event of a roll over...this all came about from a buddy of mine rolling his HB and all the bolts sheared from his body lift and the cab separated from the frame...he walked away but thats something you dont really want think you would need both sway bars no matter what. WTF u talkin bout Willis? haha no sway bars would stay in place and could possibly be improved...I need to break out my RVD book and start going through the suspension on the pathy and see what could be done to decrease roll at an increased CG Edited April 15, 2008 by unccpathfinder Link to comment Share on other sites More sharing options...
Bart68 Posted April 15, 2008 Share Posted April 15, 2008 (edited) It may sound like a ridgid lift on paper but trust me it's not, I helped a Buddy put a 5 inch body lift in his 66 Bronco very much the way you just described it and it was a bad idea. We lengthened the steering colum, shifters, lowered the rad, built new bumpers to cover the huge gap, we made gap hiders for the frame to body space and just a whole lot more and it didn't look to bad.... BUT after a mild off road trip with only average amount of flexing and just a couple of nasty mud holes we went back to his place to wash out under the Bronco and re-tourque everything. FOUR of the mounts were it was welded to frame had cracked and the back 2 were almost ready to fall out on either side of our welds it wasn't the welds that were breaking it was the frame that was never designed for that type of a lift. We then proceeded to remove that frame and put a whole new frame under it with a proper body lift. Oh and we used the proper body bushings with the 5 inch lift. Maybe we did something wrong in our fabrication but I myself will never do something like that again. Edited April 15, 2008 by Bart68 Link to comment Share on other sites More sharing options...
GrimGreg Posted April 15, 2008 Share Posted April 15, 2008 If they cracked, then they weren't engineered or built correctly for the vehicle. Link to comment Share on other sites More sharing options...
Bart68 Posted April 15, 2008 Share Posted April 15, 2008 If they cracked, then they weren't engineered or built correctly for the vehicle. It was the frame that cracked on either sides of the weld, not the mounts or the welds but the frame couldn't take the added stress, maybe if a person adds extra plates and then welds to those to give it more of a footing. Link to comment Share on other sites More sharing options...
GrimGreg Posted April 15, 2008 Share Posted April 15, 2008 It could have been the heat stress from the welds that cracked the frame also... Besides, Ford, they break if you look at em funny. Link to comment Share on other sites More sharing options...
unccpathfinder Posted April 16, 2008 Author Share Posted April 16, 2008 (edited) I find it easy to believe that with improper welding techniques and heat treat of the steel post weld that the frame would break way b4 the weld would it typically happens that way... I got 5 mins so this is what I had in mind for basic starters granted I know a couple of the mounts would need to be way different than this its just a concept...red and brown are the side plates brown has no holes...the yellow is the close out and green is the frame I'll elaborate more on the previous comments but I've gotta get going...but I'm still thinking with 3-5 bushing style bolts through the frame will be sufficient over welding or combine those with the welds for a failproof "joint" had time in a commercial go do another concept for the other mounts...I know some have that semicircle offset pad (i think its the 2 middle body mount points or maybe the rear 2...I have to look at it again sometime Edited April 16, 2008 by unccpathfinder Link to comment Share on other sites More sharing options...
88pathoffroad Posted April 16, 2008 Share Posted April 16, 2008 I think you'd have to re-engineer the shifters and e-brake setup at a minimum to put that much body lift on. The only time I've ever seen a problem with a BL was my friend Steve-O, who nose-dived his Pathy at the sand dunes...the whole body shifted forward a little. I dunno about solid mounts. A better way to do that would be to brace each body mount to the next mount with tubing like they did with that Japanese 6" body lift I saw a while back. All the body mounts were braced together with pieces of tubing. Link to comment Share on other sites More sharing options...
Bart68 Posted April 16, 2008 Share Posted April 16, 2008 See the way you have it shown is WAY better than the way we did it and yes we had a less than perfect welder actually it was just a buzz box so if you have a good mig you would probably stand a much better chance at it not cracking on you. But still you have a ton of work in front of you for fabbing up all the extension pieces that you will need. Good luck on it and keep us posted with your progress. Link to comment Share on other sites More sharing options...
sammyb33 Posted April 16, 2008 Share Posted April 16, 2008 the only question i have is this, what are you trying to gain by doing all of this work? are you planning on running 35s? If so, I dont feel like you would be actually gaining much but bigger tires on an already weak setup. But that is just my opinion, and maybe you have other ideas afterwards like a drivetrain lift or something (even though stock it is tucked up quite nicely). I just feel that you would be better off with a 2 inch BL and then solid axling it and keeping it low. That was my plan but i ended up close to 8 inches of lift...Im hoping it will settle, otherwise im going to be pulling off my coil buckets and putting them higher and cutting more fender away.... Link to comment Share on other sites More sharing options...
unccpathfinder Posted April 16, 2008 Author Share Posted April 16, 2008 (edited) This is all probably going to take a good 2 years of work...I still have to finish getting the pathy frame and body modeled up and see what I do to optimize lift for fit and function but B4 I get into any hardcore design I figured I'd get some of the "pro's" opinion I have also thought about creating something similar to the Xterra Calmini SAS kit for WD21's b/c I do have a dana 44 sitting in my garage that I'm selling for someone but I just cant get it sold for the price he wants...I'm also looking at CL's and possibly other improvements to the pathy but I just need time and opinions b/c I have the ability to run the calcs and create the models/working prints With this all being said does anyone know of anywhere you can rent a 4 point scale...by this I mean a scale that will allow me to see what the static load at each tire is to help locate the CG fwd/aft and inbd/outbd OR a mobile scale that can handle up to about 1500lbs b/c I could take a weight at each wheel individually Ohh yea and 88 I would incorporate the same type damper setup like nissan has in the stock body mounts Edited April 16, 2008 by unccpathfinder Link to comment Share on other sites More sharing options...
87pathy Posted April 16, 2008 Share Posted April 16, 2008 if your going to be welding that kind of support to the body mount, it would be easier to cut off teh old ones and move them up 3" Link to comment Share on other sites More sharing options...
Nissyota88 Posted April 16, 2008 Share Posted April 16, 2008 i know a guy that use hockey pucks for a bl Link to comment Share on other sites More sharing options...
shift220 Posted April 18, 2008 Share Posted April 18, 2008 I think your over-thinking this whole bodylift thing. It really isn't necessary to engineer such complex designs for body mounts. If your worried about bending bolts, either use larger diameter ones or do something like this to eliminate the bending moments on them. Provided there is enough room on the under the body and on the frame. Just imagine this sitting over the stock mount, the 4-5" bushing sitting snuggly in the brace and the body mounted on top. Link to comment Share on other sites More sharing options...
unccpathfinder Posted April 18, 2008 Author Share Posted April 18, 2008 hmm interesting...I'm not sure I completely follow...I guess what I was getting at with bolt bending is with the BL you run the bolt up through the frame/mount through the bushings which in turn run through the truck which a larger Dia would help but getting large dia bolts 5-7" long gets expensive fast so from the image it looks like the 2 diagonals would attach to the frame and the center cylinder would "hover" above the exiting mount or would it go straight down and contact the frame? Link to comment Share on other sites More sharing options...
89_trailboss Posted April 18, 2008 Share Posted April 18, 2008 you would literaly be able to spit between you body and frame with a 6" body lift. its a completely stupid never mind illegal thing to do, IMHO. after all the time it would take to relocate everything, you could have spent a few more hours(if that) and done a simple leaf sprung sas. whats wrong with a simple 3+3? Link to comment Share on other sites More sharing options...
unccpathfinder Posted April 18, 2008 Author Share Posted April 18, 2008 (edited) whats wrong with a simple 3+3? b/c I'm not a simple person...I'm not a "hey lets do what everyone else has done" never have and never will its a completely stupid never mind illegal thing to do I don't see why its stupid...if I can substantiate it as safe with actual calculations is a lot more than saying hey I can hack up my IFS and bolt/weld in some leaf's that I have no idea how I'm changing the capability of the vehicle characteristics (which could be derived as what I'm doing) but I just dont like SAS and nevermind it being illegal...my truck as it sits is already illegal in this state (since I already did the not so simple task of converting my TBI into a MPFI) but I'm working towards fixing that...Plus I dont like how SAS vehicles ride, drive or handle Another reason I think you could do the 4 or 6" BL is to get bigger tires and more GC... with this being said I was thinking more about it and if I did that and could still fit 32's or 33's under it without using a suspension lift since those tend to wear parts out and with the SL the only ground clearance your gaining in reality is 1/2" if you go up from a 31 to a 32" tire which if you deflate it to 20-25lb then you've just lost that lift as far as high centering your rear axle and front skiddy goes...now I will say that the 3" SL does give you more frame ground clearance but I don't really know how much of that is an advantage esp if the TM lift is used I have a long way to go B4 I could even come close to figuring out what is actually possible...I mean I've barely got the frame started in cad b/c Nissans dimensions in the FSM don't correlate to one another... EDIT: it looks like in CA a body lift can be no more than 5" with a max frame height of 23"s http://www.dmv.ca.gov/pubs/vctop/d12/vc24008_5.htm Edited April 18, 2008 by unccpathfinder Link to comment Share on other sites More sharing options...
unccpathfinder Posted April 18, 2008 Author Share Posted April 18, 2008 Heres what I have so far for the frame...if I get about 4 hrs tomorrow I hope to have it in 3D Link to comment Share on other sites More sharing options...
Mr. Pickles Posted April 18, 2008 Share Posted April 18, 2008 I really think this kind of body lift is not the right tree to be barking up. If and when you can pull it off and stabilize the whole structure on top of this lift, the leverage on a 6" body lift is going to be far more than on a standard 2-3" one. I'm sure you can build the mounts and frame to the end of the earth to accomodate the whole thing, but it seems that your base argument is that you don't like SAS because of the ride, which makes no sense at all. You're trying to design by body lift while ignoring the suspension, which built out, leaves you with a really tall truck that's about as practical to drive as a monster truck. Extending the body to big heights above the frame and suspension will make it behave essentially like a big pendulum.. Link to comment Share on other sites More sharing options...
unccpathfinder Posted April 18, 2008 Author Share Posted April 18, 2008 if the roll center for the body is currently 12" above the frame and say it going around a sharp turn it gives you a 3G load and say the body weighs $500lbs simplifying everything down to a reasonable calc that can be done in a forum...your looking at a 1500lb force which would create a 1500 ft-lb moment with respect to the frame if you look at a 3" body lift you would have a 1875 ft-lb moment and if you went the total 5" (according to CA) would provide a 2125 ft lb moment at the CG of the body which is 70% higher than the stock roll moment which as a wild guess still puts me at least 30% under the design condition and possibly lower than that if they took more than a SF of 2 which was probably more like 3 or 4 to reduce the "pendulum" effect there would need to be suspension changes possibly with spring rates and shocks but it seems that your base argument is that you don't like SAS because of the ride, which makes no sense at all I don't like SAS but thats a personal preference and no the main argument was to squeeze bigger tires under the pathy without HD sheetmetal mods and if that couldn't be obtained safely then I feel that it would be an upgrade for the current BL's available b/c of what I've seen happen to trucks with BL's that have rolled or been in wrecks and the lift doesn't accommodate for those types of situations You're trying to design by body lift while ignoring the suspension, which built out, leaves you with a really tall truck that's about as practical to drive as a monster truck. I never said ignore the suspension...I said it may be a possibility to add a body lift without a susp lift to obtain the same "ground clearance" and I believe a sound body lift (by sound I mean isn't going to come detached from the frame in a wreck) the CG of the chassis is more than likely below the frame or right at the CL of the frame as you increase the susp side of things your roll moment increases much more than it does for the body being that the body probably weigh's 1/2 to 1/4 that of the chassis so in theory you can overcome the change in the roll moment of the body easier than you can that of the chassis but you better believe that if I completed calcs and it looks shaky I wouldnt do it What is the sole purpose of a body lift anyways? To add larger tires or gain more clearance from the frame in the engine bay or some other desired mod...I am not familiar with the TT setup but if you got say 4" or 5" of BL instead of 2-3 could you install a TT by fabbing in some motor mounts that would position the motor in line with the radiator still and in the stock location but give a ton more room for plumbing and for the turbo's? Link to comment Share on other sites More sharing options...
shift220 Posted April 18, 2008 Share Posted April 18, 2008 if the roll center for the body is currently 12" above the frame and say it going around a sharp turn it gives you a 3G load and say the body weighs $500lbs simplifying everything down to a reasonable calc that can be done in a forum...your looking at a 1500lb force which would create a 1500 ft-lb moment with respect to the frame if you look at a 3" body lift you would have a 1875 ft-lb moment and if you went the total 5" (according to CA) would provide a 2125 ft lb moment at the CG of the body which is 70% higher than the stock roll moment which as a wild guess still puts me at least 30% under the design condition and possibly lower than that if they took more than a SF of 2 which was probably more like 3 or 4 I don't think you'll have a problem with normal and tangential acceleration loads on the mounts even with just long 5" bushings. With driving on the road and mild offroading I wouldn't expect any trouble. Its the impulses you will receive during more extreme offroading that will cause things to bend or break. But again, with 10 mounting points (?) and very rigid bodylift blocks, only mild bracing is really needed. Link to comment Share on other sites More sharing options...
MikeV Posted April 18, 2008 Share Posted April 18, 2008 Wish I had that much spare time on my hands! I definately wouldn't re-engineer something that works fine already, but I hear Cali is boring enough to push people to do crazy things. It's all the Dank and rice fields burnin'! Link to comment Share on other sites More sharing options...
unccpathfinder Posted April 18, 2008 Author Share Posted April 18, 2008 I don't think you'll have a problem with normal and tangential acceleration loads on the mounts even with just long 5" bushings. With driving on the road and mild offroading I wouldn't expect any trouble. Its the impulses you will receive during more extreme offroading that will cause things to bend or break. But again, with 10 mounting points (?) and very rigid bodylift blocks, only mild bracing is really needed. I'm with you on that...Once I get into the real design I want to be as conservative as I can on calcs and still maintain a low weight gain by increasing the safety...becoming an engineer has really ruined life for me...I start looking at things and go damn thats some scary @!*%... Wish I had that much spare time on my hands!I definately wouldn't re-engineer something that works fine already, but I hear Cali is boring enough to push people to do crazy things. It's all the Dank and rice fields burnin'! Haha...well I don't really have a ton of time on my hands but they're fixing to start laying off at work so I'm entertaining/retraining myself to get back into some hardcore engineering to sell myself on the market and I miss the pathy and don't have time to work on it so I may as well better my career and possibly get some other options out there for the WD21's b/c theres an offroad supplier that will possibly buy my designs if I provide the engineering work so they can sign off on it...granted if they dont I can have my own stuff for my own rig and know its good without worrying about who was riding with me and if I was going to kill them or not Link to comment Share on other sites More sharing options...
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