Marlin Crawler Formula Toyota Buildup

[freds40]

The studs thread into the housing so either double nut it and remove the stud or use a stud remover and pull them. The bolts then just thread back into the holes with no additional mods.

[raybie]

The MC07 is $329

The MC08 and the Rotated MC08 are both $399

web page say MC08 is $499??  I like $399 better.

[Hyena]

To double nut it you first
Put ont nut onto the stud, don't tighten it down
Then put another nut onto the stud, tighten the second nut to the first nut.
Then loosen the stud out by loosening the inner nut. 

[Marketing]

The Champion Beadlock wheels came in so it's time to put some bling into this project.

I originally wanted to go with 39" X 13.50 tires on 10" wide wheels. Andy has been running this combination on his buggy and has yet to brake his ringed Londfield yet with over a year of use. Andy's buggy is not running under the stress of competition, that's going to be harder on the axles. Also in talking with Camo about the courses we are expecting to see, a light came on in my head. My gut reaction at first was to go with the largest tire I could (39 or 40). Then I thought about the courses for this class. These courses are layed out for full bodied, modified Jeeps running 37" tires. Going too tall could be a challenge in tippy conditions. The Jeeps will be allowed front burn cases like Atlas or D300. Going over the courses I think the light weight, tube body Ftoys will have a bit of an advantage over the full bodied jeeps. The jeeps will have an advantage in turning with the front dig and short wheel base. Many of the Ftoy competitors this year talked a lot about how it came down to maneuvering between cones. This is different than the top classes. For the top classes it's often about how much throttle a rig can handle to rocket up a steep climb. Horsepower, traction, clearance and the rigs light weight are the keys to getting over the top courses.

There are a lot of different ideas when it comes to tire/wheel combinations. We have decided after much thought to run 38" X 12.50 TSL on 8" Champion beadlock wheels.  Normally a 10" wheel would be used with this tire, the 8" wheel will draw the side walls of the tire in. This will cause the tire to stand a little taller and narrower than it would on an 10" wheel. It also has the advantage of reducing the need for as much wheel spacer. We originally put on 2" wheel spaces in anticipation of 39" tires. These spacers were swapped out for a set of 1.25" front spacers. With the steering stops backed out we can still go lock to lock with out hitting the tire on the leaf springs.

Every choice has pros and cons. I know some will be running larger tires but will this be a disadvantage in off camber sections? Could be. Our tire choice will narrow the front end nearly 4". This will allow for a little more maneuverability but will also reduce stability.

Ok about the wheels:

The American Baja 15 X 8 wheels with Champion beadlocks 15 X 8 weigh 23lbs each.

The Swamper TSL tires weigh 75.6 lbs each, ungrooved.

Ok here are some photos....

[lilbuddy]

Hey Chris, its coming along very well and looking great. Those rims and tires look pretty sweet on the frame. Cant wait to see us done and Keep us posted on the progress. I enjoy taking a look at it. 

Chris

[Marketing]

To double nut it you first
Put ont nut onto the stud, don't tighten it down
Then put another nut onto the stud, tighten the second nut to the first nut.
Then loosen the stud out by loosening the inner nut. 

Yep just double nut it and remove it.

[WHITE_TRASH]

8" wheels are a very good choice indeed.  I had the same tires on a 10" wheel for about a week, then swapped them for a set of 7" wheels.  People thought I was nuts for doing it but I do dumb stuff like that.  The 10" wheels made the sidewalls stand out way more than I liked, I could envision a tree root knocking the bead off or stabbing the sidewall.  The 7's tucked the bead in very nicely and I could air way down with no issues.  The sidewall on those tires is pretty stiff so I cant see you guys having any stability issues when running low pressures.

[dirtyskivies]

damn those are nice wheels, do you have any pricing info?

[Bazzi]

nice buldup. what about the engine???  what mods are you gonna do???
I am rebulding a 22re engine right now. and would like the info of what to do

[Marketing]

Check out our new Beadlock Wheel Page:

http://www.marlincrawler.com/wheels.html

We have the 15X8's for $257 and the 15X10's for $267 per wheel. Price includes wide polished rings and hardware (as shown in photo).

[Marketing]

nice buldup. what about the engine???  what mods are you gonna do???
I am rebulding a 22re engine right now. and would like the info of what to do

Head porting and .020 over pistions are all that we are planning for the motor. It will be a nearly stock rebuilt motor.

[KYOTA]

Looking good love those wheels 

[FATB0Y]

 gotta love the factor

[Hyena]

It's comign along nicely.  I can't wait to see it done and in comps.

[Jared]

same here brad... ill go to the comps just to see one of my favorite companies compete.... keep it up guys.... 

[Marketing]

Head Work

Using a large Dremel tool with an auger bit, Marlin spent an hour hogging out the intake and exports for better air flow into the cylinders.


The stock valves were ground with Marlin's special 3 angle grind and installed into the head. The head was surfaced on our in house surfacing machine.


High quality steel Timeserts are installed into each intake and exhaust stud hole. These reduce striped threads when removing and reinstalling manifolds.


Now with the block and head finished it's time to bolt the motor together.

[Marketing]

The head we are using was from a motor that was badly overheated, causing the head to warp. When doing the valve job it took .010" of machining to get the surface of the head straight. When fitting the cam into the head, Marlin found the top of head had also warped up in the middle. To measure this the cam was placed in the head and feeler gauges were used to measure the gaps between the cam and the bearing surfaces in the head. A small gap was found in the center bearing cam cap.



To repair the bearing, the face of the bearing cap was put on a belt sander and a few thousands was removed from it. Next a line boring tool was installed in place of the cam and the center cap installed. The boring tool created a new, correctly positioned hole in the head.





Oil pickup tubes are installed into the short block.


The finished motor is ready to drop in for it's first test fitting.

[FATB0Y]

  lookin' good

[Marketing]

Instead of using front manual locking hubs, we will be using drive flanges. These are simple plates with splines inside that lock the axle shaft to the hub assembly. With drive flanges there is no ability to lock or unlock, they are simply locked all the time. We won't be driving this buggy on any streets or highways.


These drive flanges are from an Australian spec 1982 FJ40. In the USA this cruiser was equipped with manual hubs, but in Australia drive flanges are standard equipment. The drive flanges weigh 1.3 lbs each, compared to 3lbs each for the manual hubs. They are 1.5" shorter than standard pickup hubs. These flanges were chosen to allow drilling and installing more dowels. There is room to install 4 additional pins for added strength. Some drive flanges, like those on FJ80 cruisers are cut in such a way that only the two stock dowel pins can be used. Due to time constrains we are going to use them as is for now, but later we will show installing the additional pins.


Drive flanges install using the same cones, washers and nuts as the stock hubs. The original outer birfield snap ring is also used.

[Marketing]

Next the newly rebuilt motor is temporally installed into the chassis on the stock motor mounts. In this class you must put the radiator in front of the motor. The chassis is designed assuming the engine is going to be moved back 8". There is a lot of debate on where to put the motor for best performance. Some prefer the truck to be as close to a 50/50 weight split as possible. Others believe that the more weight you have up front the better balanced the weight will be when crawling uphill. Currently the top trucks in the unlimited classes of competition run rear engine buggies with the driver all the way forward. These trucks run a nearly 50/50 weight split.

Now that we have a motor, radiator, steering box and winch all together it is possible to figure out how the parts will fit. The winch will be placed on top of the front crossmember. We will be installing the motor back 4" and down 1" from the stock location. This will give the needed clearance for the winch and radiator while keeping about 60% of the weight on the front axle on level ground.







Using a length of tube to hold up the transfer case. The rotated adapter makes it easier to get the flat bottom we are looking for. After the motor mounts are built, a crossmember will be made to support the transfercase.

[FATB0Y]

Sweeeeeeeeet

[donkeykong]

Looking good...when do you plan on finishing this project.  Will it be ready for this summer

[Marketing]

It should be on the trails this summer. We hop eto finish before the first Calrocs event.

[Hyena]

Nice work!

[MidgetMike]

That is sweet    can't wait to see it perform this summer   

[TrackVino]

Really nice. 

[Marketing]

Today Andy repositioned the shackle mount in the frame. This was done to both increase shackle angle and to decrease lift a little bit. It also help rotate the front pinion up higher.

Using a hole saw to cut the new tube holes


New and old tubes in frame




Old tubes torched out


Hole that gets plugged


Plate inside of frame for extra strength


Shackle angle will increase even more when the all the weight is on the springs. We fully expect that the shackle will hit the frame on compression. After ramp testing, the frame will be notched and clearanced allowing the shackle to swing up into the frame about 1".

[Hyena]

Thats a pretty cool trick.

[KYOTA]

I was going to ask about a cap for the birf end on those drive flanges but got my answer on the PBB thread. I like the idea of notching the frame to allow the shackles more clearance. You guys going to bring it to the roundup?

[donkeykong]

Are you guys planning on competing and if so are you also going to run it at the regular events marlin go's to  I.E. the Rubithon, 4Runner jamboree and such