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Buggy Build

2xtreme

NAXJA Forum User
Location
Kayak Pt, WA
Don't get too excited. Just planning at the moment. Considering my record so far it could be a while before I start anything but I thought I would see what you guys think and I would appreciate any input to make sure I am working in the right direction before I start bending tube and collecting parts.

A little history. I have wanted to build a truck from scratch for as long as I can remember. Over the years it has gone from a primarily "expedition" type vehicle to more recently a rock buggy that can handle the more typical trails that we have here in the NW. With that in mind my previous "theoretical" build (Classic Range Rover, Mogs, 42's) has gotten way out of control and is no longer what I really want to build for several reasons and I have decided to quite that project, before it is even complete on paper ;).

1. My Priorities for this build is to build a competition style rock buggy that is capable of going fast (KOH is probably the closest "style" of rig in my mind). I have no intention of competing in anything but want a simple, dependable, fun vehicle that I can be proud of running on any trail. I don't need space for anything other than 2 people and a day's worth of gear/food. I really want a "simplistic design". Should I be concerned about "registering" this vehicle, how could I do this since most of our trails are supposed to be "street legal" only?
1. To build a totally custom tube frame buggy (Comp/KOH style buggy)
2. 2 seats, reasonable cost ($10K ?), light weight (2500lbs wet, trail ready).

2. Tires. My belief is that this is what the vehicle will be built around, this is really what drives everything else when you start from scratch. I want something big enough to try ANY obstacle but small enough to make the trails still fun. Any reason I should consider going larger than 37's? I am absolutely opposed to going larger than 40's for this build.
1. 37" (Krawlers, Treppadores, Creepies, Irok) ?
2. 17" bead locks (Walker Evan's probably)

3. Axles. This is an area I want particular input. I am not a toyota guy but from my limited understanding it seems like this is a good choice. I should be able to run a plenty strong Toyota front and rear axle (8" or bigger derivatives of these) with Bobby Long should easily handle the 37" tires under a light weight buggy. I still have a bunch of research to do here but it seems like there is a large selection of center sections, shafts replacements, breaks, etc that would be reasonably easy, reasonable cost, light weight, appropriate width for our trails. Anyone think I should go another direction or have experience in this area they would like to share?
1. Toyota Axles, disks front and rear
2. ARB/Spool
3. Should I consider cutting breaks in the rear?
4. 5.38 gears

4. Tube Frame. I want a simple, small, light, easily upgradeable if needed, but strong enough for comp use if I wanted to (NOT PLANNED OR LIKELY!). Would you change the wheel base? I would love to do a mid engine but I think it complicates things too much to consider this?
1. Bent Fabrications "Cliffhanger" is my favorite at this time. http://http://www.pirate4x4.com/forum/showthread.php?t=675157.
2. About 105" wheel base
3. "Traditional" Front engine

5. Suspension. Can anyone convince me of why I would prefer something different than this? I understand there are some advantages to 3 link with TB's, what do you guys think?
1. 4 link double triangulated front and rear.
2. 14" - 16" air or coil over air shocks, with by-pass.

6. Drivetrain. This is another area I would like specific input. 4 cylinder (probably turbo) with as much low end power as possible (I have heard of several ideas but would like to see what you guys can suggest). Keep in mind it should be light weight, reasonably inexpensive and accesible (No Cosworths :laugh:). I want to match it with a AT and probably a Stack or Atlas (not far enough along to pick gear ratio's yet). Priority again will be weight and space for the front suspension. Bonus is if the engine and AT come in the same vehicle :eyes:.

7. Steering. Full hydro, double ended ram, high steer.

8. What programs should I use to "design" this buggy frame to assist with my 4 link calculations, bends, etc?

Convince me I should consider something different :moon:
Michael
 
10k is not enough.

full hydro is $1000 no matter how you cut it, and that doesnt include a power steering pump, a steering wheel, or a steering column (unless you're comfortable having an orbital valve with high pressure fluid right above your crotch) - figure $1500 before thats done.
Atlas / Stak is like $3000 before it gets to your door
Airshocks are $400 a pop = $1600 for 4, C/O's are closer to $800 each by the time you get springs, tripple rate hardware, reservors, etc. on them = $3000...

37" Maxxis tires (at competitor pricing) are $300 each... $450 if not competing and want the stickeys... so say you can get a discount and get them at $300 - $1200
17" beadlocks - another $250 per corner - another grand...

then you need $700 worth of good seats (these are a safety item, dont skimp here :wierd:)

and $1500 worth of 1.75" tube, $700 worth of other tube sizes 1.5, 1.25, 1"

Links, joints, weld in bungs, tabs, fuel cell, fuel pump, brake pedals, gas pedals, radiator... $1000 easy.

oh yeah, a turboed 4cyl, a trans - another $1500?

And I think anything less than a V6 is going to leave you wanting more...

I think you better save up $20k to start, or lower your goals a bit...

something like this might be worth buying and stealing parts - or just wheeling -
http://www.pirate4x4.com/forum/showthread.php?t=827762
 
Dont play with the toyota stuff go 60's. Its the last axle you will buy. I wheel with some buggy guys and most all of them run 60s just for that reason. Over the years running Reiter I have seen way more yota breaks then D44's and 60's on 37's.

my .02
 
Excellent points so far.
Rod, I should have double checked that, thanks for pointing it out.

Opie, Your input is excellent, I hadn't looked at costs at all and filling some of this information into my spreadsheet has made me realize that it all adds up fast ;) I do plan on getting a bunch of this stuff used or already built to save on costs (wheels/tires, Axles?, engine/tranny, etc). Either way, your $20K mark is probably MUCH more accurate. I agree that puchasing something like that used buggy makes much more sense and is pretty damn close to what I want, but I really do want to build one and would prefer not to buy one (although I am not totally ruling this out yet).

Talk to me more about the not being happy with at least a V6.......

Dave, the toy axles I am thinking would likely be there FJ80 axles or at least9.5" ring gear centers not the typical 8" stuff we see all day long. I just don't want the extra weight of the 60's if at all possible.

Michael
 
V6 Ideas,
Have you researched the AW4 engine swaps that can be had using either a 2.5 bellhousing or an Isuzu V6 AW4 bellhousing. You can run anything from a 2.8 Chev to a 3.4 Chev or even a Northstar V8, actually it's most any GM 60° V6 or V8 engine.
 
Wow Michael, I had no idea you were interested in building a buggy. Very cool!

I guess I should call you one of these days.

Dave, the toy axles I am thinking would likely be there FJ80 axles or at least9.5" ring gear centers not the typical 8" stuff we see all day long. I just don't want the extra weight of the 60's if at all possible.

Michael

What about 9" housings front and rear? You could run regular low pinion center sections for not much cash, or step up to true high 9's if you need/can afford them. The front would be a more expensive since you need to find 60 knuckles and C's, brakes, whatnot.
 
What about 9" housings front and rear? You could run regular low pinion center sections for not much cash, or step up to true high 9's if you need/can afford them. The front would be a more expensive since you need to find 60 knuckles and C's, brakes, whatnot.

or run the rear engine that he is talking about, and run LP9's flipped - cheap trueHi9!
Talk to me more about the not being happy with at least a V6.......

As I've cut more and more off my junk, and moved towards a 'make it or die trying' attitude, I've noticed that more and more momentum is being used, and more and more 'saves' where I've wanted to be able to drive out of things - and the 4.0L is 'enough' sometimes, but I wish I had something that rev'ed faster, and made more power - so I could 'drive out' of stuff.

I've wheeled with a lot of toyota's, and those guys seem to have a 'if I cant crawl it, I cant make it' type of rig - that just doesnt have the 'oomph' to get up and go when a little wheel speed, and little momentum might have gotten them there.

I cant imagine having anything less than the 4.0L that I have - and I think that I'd hate a 4cyl.

Though short of going to an aluminum blocked Vortec V6, I dont think that your 2500lb weight is on par. I'd expect more like 3300 for the kind of buggy that you're talking about.

The toyota 9.xx" stuff is nice, but its not all that common... Not that much aftermarket support if you go down that road and something doesnt work 100%.

_____________________

If you buy someone else's buggy, and use most or all of the parts, and make your own chassis - I think that would be both gratifying and cost effective.

I know that for me, building the chassis would be fun. Being nickle and dimed to death with small parts and spending hours cutting down a wiring harness would not be.
 
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first off, I agree very much with all of the comments so far.

1. 9's. My first instinct was a 9" and 609 front. Costs on the 609 don't look that cheap that I have researched so far but I need to look into this more. When I was thinking this route it also make the rear engine idea much more doable (I have not looked into the 9" flip oiling issues but I understand that others have made them work so I should be able to sort this issue out). I am still not convinced that the 9.5" toy stuff isn't a good/easier/cheaper route. They may be harder to find and the housing maybe a little more expensive to start with but they have ARB/35spline shafts/Disk breaks all available. Again, the flipped 9's and rear engine would be MUCH cooler.

2. Engine. My limited research so far tells me that I should be able to get a 4 cylinder (mild turbo) engine to about double the HP (300HP) that my current 4.0 gets (150HP?). And even at a reasonably low rpm. Given that my crawl ratio will probably be more than double what I have now, this buggy will weight about 1/2 of what my XJ weights, and my driving style (the complete oposite to yours Opie ;). Your Jeep rarely is off the rev limiter and mine has probably never seen it) my thoughts were that I would end up less weight, smaller fuel cell, smaller radiator, better visibility, quieter engine, etc? To be honest, there is probably VERY little difference in weight between a 4cylinder and a aluminum 6 or even 8. What may be more significant is the availability/cost/reliability/size/weight of the engine/tranny combo. I am not opposed to a V6 but I would like to see if I can't find a 4cylinder that would do the job better in a smaller package.

3. I think I should be able to get this buggy under 2000lb dry and 2500lbs ready for the trail. It will depend somewhat on the engine/tranny, tires/wheels, axle selection but it seems that it should be doable if it is designed well enough. It seems that there are a number on 1 ton axles with V8's that are still very close to the 2500lb dry mark. I won't really know till I get there but at least this gives me a goal to work towards.

4. I agree with you 100% on the buy/make perspective. There are all sorts of semi built rigs that already have the axles, wheels, tires, drivetrain that I could swap into the buggy (the fun part of the project) but most of them I would have to compromise some of the parts and for me it is easier to piece it together over time as money is available than to buy something already done.

What about the licensing?
What about programs I should start playing with for design?

Thanks for the input guys.
Michael
 
Sweet! I would love to build a buggy as well. Are you ever not in research mode? I'm on the buy stuff slowly plan now with 220V welder and a air/hydro bender, so about 5% ready to build.

Do you plan on having a heater?

Do you plan on having a roof and windsheild?

These two are mandatory for my wife, just something to consider.

2. Engine.


Have you considered a VR6? It's a little on the heavy side and impossible to find adapters for. I think the VR6 is THE PERFECT package for a small two seat buggy. The VR6 is only a few inches wider and longer than a 4Cylinder. The 2005 Passat version had around 240HP and I've read about 500+ HP with 1 turbo :lickout:. Adapters exist to mate the VR6 to most VW platforms and some Audi's. I'm being vague on the models because I simply don't know which VW or AUDI trannys will work with the aftermarket adapters.

Adapters exist to mate the VW TDIs to the Suzuki Samurai. The TDI/Sammy adapters are very crude 3/8" plate so one would think the Vr6/Toyota swap is possible??? Do you see my logic? It could work, right?

What about the licensing?

I researched building a LOCOST and had a very preliminary conversation with a WSP inspector. Other than the obvious stuff (lights, horn, wipers, fenders, windshield) the inspector's main concern was that unmodified DOT equipment be used on the brakes, steering, and anywhere else where possible. I was also asked to bring receipts for the unmodified DOT equipment, even if its from a junk yard. The inspector specifically stressed not to use off-road components. Apperently other builders of small kit-type cars similar the LOCOST, like to use non DOT rack and pinions.


What about programs I should start playing with for design?

I intend to use Bend Tech Pro ($275 on Pirate), Is there another choice, or are you considering a full blown CAD software?

You probably know this but the July issue of Petersons had a "links for dummies":

- try to make your links parallel when veiwed from the side
- make them as long as you reasonably can
- make them as flat as you reasonably can
- make the roll axis as high as you reasonably can
- vertical separation should be 6" or more. More especially for more horsepower and/or bigger tires.
- make the triangulated portion 40 degrees or more for decent lateral control.

I plan to follow the above and add in as much adjustability as possible. Here's a good 4-link site: http://www.azrockcrawler.com/_images/tech/2007/6-27-074link/4linksurvey.html
 
2. Engine. My limited research so far tells me that I should be able to get a 4 cylinder (mild turbo) engine to about double the HP (300HP) that my current 4.0 gets (150HP?). And even at a reasonably low rpm. Given that my crawl ratio will probably be more than double what I have now, this buggy will weight about 1/2 of what my XJ weights, and my driving style (the complete oposite to yours Opie ;). Your Jeep rarely is off the rev limiter and mine has probably never seen it) my thoughts were that I would end up less weight, smaller fuel cell, smaller radiator, better visibility, quieter engine, etc?

What about the licensing?
What about programs I should start playing with for design?

Thanks for the input guys.
Michael

Engine - you dont think that your driving style will change with a vehicle that you know you wont do any damage to, and that you'll be safe in?

I didnt always drive the way that I do... :gee:

My rig has WA ATV tags (basically). I brought them my jeep cherokee title and said I want this to be an off raod rig only...

might be worth spending $50 on some craigslist vehicle and getting some vin plates, clean title, and a grill for some style. :dunce:

Google sketch-up is free, and semi-easy to play around with. Bend Tech is highly praised as an easy to use software.

I'm a bigger fan of pen and paper and wasted tube. :eek:wl:
 
No, I don't ever stop researching something (I blame it on being an engineer ;)) but it drives my poor wife nuts. The good side of it is that it is exceptionally rare that I make a decision and regret it later ;).

Engine. Yes, I have considered a VR6. reasonably light, lots of power potential and very compact, I have not looked into a tranny to match it up to. The engine/tranny area is really where I have the most research to do. I just want to make sure I make the best compromise for weight/power/torque/size that I can, particularly if it is going in the back (I don't want to have to add water to the front tires to make it climb ;) ). I agree, my driving style might change, so you saying I should put in a LSx :). So what V6 would you guys pick (with a AT)?

Roof? Yes, basic roof.
Heater? Not sure yet, might not make that decision till after it is built?
Glass? No, helmet and gogles.
sides will be polycarbonate and painted.
I will still have my XJ for "family" wheeling.

Licensing. I do have a clean title car with a grill ;) I could use those plates and vin, I guess that is the easiest thing to do. Opie, do you have plates or just the sticker?

I will see what I can find on line to start with. I have a basic bending program that came with my bender that I have not looked at yet. I understand the basic principals, but really want to play more with both a double triangulated 4 link and 3 link to compare the numbers in more detail to help decide which way to end up going (I get the impression the 3 link might have some significant advantages on the roll center).

I looked in the flipped 9's more and that is looking more and more likely. I still need to price out a 609 but I think I might end up going this way.

Considering my weight goals, and the limited amout of long distance high speed stuff this thing is likely to see do I really need to consider coil overs or by pass shocks. Would typical 2.5" air, resevoirs be plenty?

Michael
 
Have you considered a VW TDI engine or a 2.8 CRD out of a liberty? the 2.8 is what Ive been looking at for a while, 177hp 295ftlbs @2k and that's stock. the newer ones do 190/345 and there are some off the shelf chips that claim 50hp/100ftlbs
 
No, I don't ever stop researching something (I blame it on being an engineer ;)) but it drives my poor wife nuts. The good side of it is that it is exceptionally rare that I make a decision and regret it later ;).

Engine. Yes, I have considered a VR6. reasonably light, lots of power potential and very compact, I have not looked into a tranny to match it up to. The engine/tranny area is really where I have the most research to do. I just want to make sure I make the best compromise for weight/power/torque/size that I can, particularly if it is going in the back (I don't want to have to add water to the front tires to make it climb ;) ). I agree, my driving style might change, so you saying I should put in a LSx :). So what V6 would you guys pick (with a AT)?

Michael

I know there are guys in South America that are bolting the TDI motor to AW4 transmissions in Suzuki's. Since the AW4/A340?30-40LE all have removable bellhousings this leaves big interchange options.
 
Wow Michael, I had no idea you were interested in building a buggy. Very cool!

I guess I should call you one of these days.

Do I smell a mind-meld of the NWHBC? Holidays are coming up, lets get together. The wives would love it.

Hans
 
Supercharge and turbo a late 90's Cummins 5.9l diesel. And what is all this engine swap talk? We are talking about a ground up buggy right? You build it to run what you want or to be universal enough to handle various choices.

As Hans mentioned we REALLY need to get together and discuss the TTCW results and consume frosty beverages..... And Plan... :cheers: I have a cooler full if the Border contingent is willing to come on down?
 
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No diesel. I love diesel's but I am not putting one in a buggy for two main reasons. They tend to be loud and they smell. There are a list of other draw backs for this type of rig but these are the two primary reasons in my book.

No turnkey. I "could" consider a built rig to start with to disasemble just of the drivetrain and axles IF the engine/tranny axles etc were all coming out of the same type of rig, but that is pretty unlikely. I enjoy the process of designing/building just as much as actually wheeling it ;)

After doing a LOT of research on engines I have discovered several things.
1. There are a LOT of different engine choices :paperwork
2. There are a LOT of issues mating each of them with a decent tranny :confused:
3. There are V8's that weight less than 4cylinders and 4 cylinders that put out more power than V8's.
4. The easy way out is to just stick a LSx in it. (That was the orginal intention after all) but would really prefer to find a better candidate (smaller, lighter, but still plenty of power).
5. I had never even considered the fact that I might find a decent engine/tranny and not be able to hook up an Atlas or Stak. I ran into this also!
6. I believe I want either a Turbo 4cylinder or Aluminum block V6. Preferably modern and easy to source.

My head is still buried in the books :looney:
Michael
 
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