Dune Buggy Help

[chevy92]

Hey y'all I'm lookin to custom fab a 4wd, 2 seater dune buggy for mud riding. I have welding experience and the guy building it with me is an expert welder, I'm a mechanic by trade & I've been doing it since I was young. So I'm not really worried about actually "doing it" but I'm having some trouble designing it. Any tips? Some of the blocks I'm having are:

What motor?
Round tubing or square?
Leaf or coil springs?
Thinking of using Toyota axles. Good idea?

 

[Griff93]

I'd figure out about what tire size you are wanting to run and build around a drivetrain suitable for that. If you are running 36s toyota axles with upgraded birfields might be fine depending on the weigh and powerplant. I wouldn't even try it with 44s and V8.

 

[Garage5.9]

straight toyota axles

 

[chevy92]

i def think im going with yota axles.

griff, why do you say not go with 44's and v8?

 

[Zelatore]

i def think im going with yota axles.

griff, why do you say not go with 44's and v8?

I may not be a big wheeler, but even with the light weight of a tube buggy don't you think 'yota axles might have just bit of an issue with big power and that much tire???





(If you were joking, please disregard....)

 

[chevy92]

zelatore, it was a serious question. and i def see what your saying about the tires and power. but the reason i asked is bc a few years ago i had a toyota on 44's with 5:11 gears in the rear end. they were stock yota axles besides the gears and they held up good. however, it was a stock yota motor so idk if they would hold up as well with more power. i would like to do a small v8, but realistically ill prolly end up doing a v6 due to the light weight of the buggy.

 

[chevy92]

I'd figure out about what tire size you are wanting to run and build around a drivetrain suitable for that. If you are running 36s toyota axles with upgraded birfields might be fine depending on the weigh and powerplant. I wouldn't even try it with 44s and V8.

i like the idea, but i have one question...if i were to do it that way, would you suggest leaving the drivetrain as is, resulting in the engine being in the front of the buggy?

 

[74grabber]

If it was me I would be designing off what parts or drivetrains I have the most stock in or are plentiful to me. I am a ford guy so I have a large abundance of 5.0/5.8 parts around as well as in storage (daily driver is a 5.0, drag car is a 5.8, wifes play car is a 5.0, cabin truck is a 5.8).

BUT my 2 seater "sand" rail is a Mr2 motor VW transmission with VW front end(Drivetarain and suspension parts are EASY to come by). The MR2 motor has WAY more power than the suspension can handle. This rail is only about 12 inches of travel (just a guess off the top of my head) but with the power and speed its capable of it needs atleast 24 or more in my opinion. Look at say CORR trucks, look at there power vs suspension travel and apply a similiar formula. No point in having 400 horse if it rattles your teeth in a suspension that cant handle the power.

So I guess to some it up figure your power requirements off of your power needed to spin the tires, gear according to your max top speed needed to clear your terrain, and OVER build the suspension (which is the expensive part).

And in all honesty for a mud bogger I would prefer to start with a willy's, bronco, blazer, power wagon chassis. Bogging is fun but in my opinion not so much fun in a rail type esp with 4 wheel drive. VERY messy and with that problems can happen when mud water gets where you don't want it.

Oh and lastly DRIVESHAFT LOOPS and WAY over build them! Driveshafts kill esp in a build like this.

 

[chevy92]

If it was me I would be designing off what parts or drivetrains I have the most stock in or are plentiful to me. I am a ford guy so I have a large abundance of 5.0/5.8 parts around as well as in storage (daily driver is a 5.0, drag car is a 5.8, wifes play car is a 5.0, cabin truck is a 5.8).

BUT my 2 seater "sand" rail is a Mr2 motor VW transmission with VW front end(Drivetarain and suspension parts are EASY to come by). The MR2 motor has WAY more power than the suspension can handle. This rail is only about 12 inches of travel (just a guess off the top of my head) but with the power and speed its capable of it needs atleast 24 or more in my opinion. Look at say CORR trucks, look at there power vs suspension travel and apply a similiar formula. No point in having 400 horse if it rattles your teeth in a suspension that cant handle the power.

So I guess to some it up figure your power requirements off of your power needed to spin the tires, gear according to your max top speed needed to clear your terrain, and OVER build the suspension (which is the expensive part).

And in all honesty for a mud bogger I would prefer to start with a willy's, bronco, blazer, power wagon chassis. Bogging is fun but in my opinion not so much fun in a rail type esp with 4 wheel drive. VERY messy and with that problems can happen when mud water gets where you don't want it.

Oh and lastly DRIVESHAFT LOOPS and WAY over build them! Driveshafts kill esp in a build like this.

thanks, i appreciate it! and if i decide to go with the custom tube chassis, im going to figure out a way to enclose it. ive def thought about going off of a chassis, but im hung up on the custom thing haha. i have a feeling i might come out of it, who knows haha

 

[chevy92]

also forgot to mention that i have a 92 toyota 4wd that doesnt run. what should i use off of it?

 

[porcupine73]

For the motor, some people like say a turbocharged unit from a Subaru STI. That will give around 300 bhp. The Subaru's are boxer motors with the cylinders 180 degrees apart for a nice low cog.

 

[74grabber]

also forgot to mention that i have a 92 toyota 4wd that doesnt run. what should i use off of it?

Why doesn't it run?

If it was me than I would be using everything fron this chassis. bassically all drivetrain parts motor/transmission, wiring, and suspension. After your done with your build sell off the un needed parts on craigslist for some extra cash to offset the cost of the build.

I would disassemble everything from the truck and use the stock suspension mounting points as a build into my new tube chassis. At that point aftermarket parts come into play or build. Need better shocks or long travel arms? Break out the credit card or build from scratch. And that continues on with everything else about that platform. Parts are plentiful and lots of forums to support the addiction and or how to's.

 

[74grabber]

For the motor, some people like say a turbocharged unit from a Subaru STI. That will give around 300 bhp. The Subaru's are boxer motors with the cylinders 180 degrees apart for a nice low cog.

Great motors! But not sure about the OP's area and being able to find one for a decent price. I kind of get the idea this is a mild budget build.

 

[porcupine73]

That's true....if you don't necessarily want that much power or forced induction, some people have been making what they call the Subaru 'frankenmotor'. Basically it is a 2.5L 4 cyl Subaru motor, but with heads from a 2.2L motor on it. That bumps up the compression and they have some other mods that go along with it; supposedly will make 180HP+.

 

[74grabber]

That's true....if you don't necessarily want that much power or forced induction, some people have been making what they call the Subaru 'frankenmotor'. Basically it is a 2.5L 4 cyl Subaru motor, but with heads from a 2.2L motor on it. That bumps up the compression and they have some other mods that go along with it; supposedly will make 180HP+.

Yep thats about the power range I would be looking into for the build if it was me. Around here in the AZ desert, plenty of bada** rock crawlers running 4 cyl or 6 cyl in the power range of 175-250ish and geared accordingly.

Some keys I would build into it no matter what the power plant

8-10:1 power to weight ratio
N/A power (keeping either all aluminum engine or all cast engine, no aluminum heads on a cast block. Cold water shock would hate to warp a head)
2 spare tires on opposite end of motor
weatherproof tool box again on opposite end of motor
windshield wipers
skid plates on a arms and chassis as much as possible using flush mount fasteners
nerf bars
snorkel fresh air intake
high mounted radiator
remote operated winch mounted on trailer hitch style with recievers on all 4 corners of the rig
2 Fire extinguishers
firewall between engine and driver
and again DRIVESHAFT LOOPS

Just add a knock down truggy frame and a powerplant, and get out the welding helmet!

 

[chevy92]

i really appreciate the help guys. yall are throwin out some good ideas. and to address the idea of the subaru motor, good idea but would i be able to find a ****** and transfer case to bolt up to it?

 

[Griff93]

I wouldn't run 44s on toyota axles because that's not enough axle to withstand the torque load with a V8. Now with a 22R that's a bit different. I've seen many guys break the factory birfields with a 22R and 35s. With it light enough and upgraded birfields I guess you could run toyota axles on a buggy without much trouble. Part of it is how/where you drive. If you really want to run a toyota axle and big tires, take a look at FJ80 axles. I've never seen or heard of a 5.11 toyota gearset. They make 4.88s, 5.29s, and 5.71s though.

 

[chevy92]

ahhh i just remembered 4:88s were in the yota, 5:11s were in the 1/8th mile drag truck lol

 

[porcupine73]

You might be able to use a Subaru manual transmission as well, though if you're running large tires it might not be quite the gear ratio you want. If you're going with AWD you might be able to use the whole Subaru drivetrain, though again the gear ratio might not be right for really large tires. Subaru MT's incorporate a center differential for the AWD so they don't have a conventional transfer case. If you're really considering a Subaru motor, these guys might know more about the drivetrain options: http://www.ultimatesubaru.org/forum/forumdisplay.php?f=30

 

[crewchief888]

Hey y'all I'm lookin to custom fab a 4wd, 2 seater dune buggy for mud riding. I have welding experience and the guy building it with me is an expert welder, I'm a mechanic by trade & I've been doing it since I was young. So I'm not really worried about actually "doing it" but I'm having some trouble designing it. Any tips? Some of the blocks I'm having are:

What motor?
Round tubing or square?
Leaf or coil springs?
Thinking of using Toyota axles. Good idea?

heres my $0.02

4.3 TBI cheap and plentiful engines around here (i'm running headers, 2" exhaust, TBI spacer, 14" KN filter)
rectangular tube main frame, everything else round tube
coils look cool, you can usually get a little more flex from them, and they cost more to start with, but leafs work just fine.
toyota axles will work, as will d30/35 or ford 8.8, wagoneer d44's would be even nicer.

staying under 35" or 36" tires will reduce parts breakage on the lighter axles, staying away from v-8's will have the same effect.

no matter what you build, you can break it if you try hard enough.

if i had toyaota stuff available, thats what i'd use, plenty of aftermarket support there, same goes for jeep stuff.

 

[Skyline]

What is your deninition of "mud riding"? How big a tire are you going to use?

Those folks that have suggested V6s or turbo 4s that might work well for a crawler, generally anything made for the mud is going to need big tires, and V8 power to spin them. Spinning big tires will break weaker axles.

I say built Dana 60's or 9" F& R, with V8 power is minimum.

 

[Sureshot]

Running 33" tires on my chipped DMax and in our mud it makes it snort if you get in deep. If you are talking serious mudding I would get all the power I could and the drivetrain to match. Rock crawling and trail driving you are slow and easy.

 

[BigAl62]

As for my .02 cents worth, I'd start with a Jeep Wrangler frame and running gear and make a body to fit it (something other than a Jeep body, otherwise why not just build a Jeep), something light weight and 2 seater. Hope this puts some ideas in your head.

 

[crewchief888]

when i decided to build another off road truck, i looked around for a vehicle that was cheap, readily available parts in the junkyard, and wasnt rusted all to hell.

around here lots of s-10 blazers and awd astro vans in the junkyards,
i got lucky and picked up my s-10 blazer with a blown engine, bad trans, no front seats and missing the ign switch, with a title.

for free.

been working on it off and on for over 4 years,
total cost approx $2500

 

[rickb801]

I'd use most of the toyota parts you have.Google "Formula Toy", if you are looking to build more of a tube type buggy not using your existing truck body.I'm not saying to build one to the rules, but use it as a overall concept.