Build The Dirt Squirrel 3.0

[DirtSquirrel]

With it being 27 degrees in the shop today, i didnt get much done. I only managed to get the atlas adapter bolted to the 700r4. I moved around the level/position of the engine/trans to what i think is going to be its final spot. I hope to start bending some tube tomorow if it isnt cold as shit again.

 

[woody]

I see an early FJ40, and an early Samauri??

Winter work sucks, don't miss that part of WI at all...

 

[DirtSquirrel]

I see an early FJ40, and an early Samauri??

Winter work sucks, don't miss that part of WI at all...

The rusty crusty 40 is mine. It’s a 74 and I just finished swapping in a turbo 3rz / w56 / mini truck t-case. It rips. The samurai is a buddys early Jimni. It’s super clean.

Winter is time to wheel usually for us here in TX.

 

[woody]

The rusty crusty 40 is mine. It’s a 74 and I just finished swapping in a turbo 3rz / w56 / mini truck t-case. It rips. The samurai is a buddys early Jimni. It’s super clean.

Winter is time to wheel usually for us here in TX.

I thought that was a Jimni.,..very cool My 2nd FJ40 was a 1974....probably still have the title somewhere...lol

 

[DirtSquirrel]

My new PRP seats came in from their black friday sale. Lowbacks, digi camo, teal, pink and gator. They are awesome.

Started bending some tube.

Sliders are 50" wide

Going to keep at this today and hopefully get the dash bar and harness bars in. Maybe the A-pillars if i can get an extra hand. So far so good.

 

[woody]

needs more triangulation.... (someone had to!)

Love my PRP's and those turned out awesome

 

[Blitz]

Those seats turned out pretty sweet. I cant wait to order my new set once im done getting mine together. The teal looks pretty good.

Really digging that small fab table.

 

[DirtSquirrel]

Dash bar and harness bars are tacked in. 50" wide at the A-Pillar and 52" wide at the B-Pillar. Dash bar raked back about 5 degrees. Hope to get the top portion of the A-Pillar bent up tomorrow and tacked in place.

 

[DirtSquirrel]

Lots of work the last 5-6 days while i was off for the holidays.

Set the A-Pillars and moved them back about an inch so i could get the dash bar down tubes to clear the head on the passenger side.

Next day, cut and spliced in the C-pillar tubes.

I intentionally left the ends long in the rear to cut them down once i have the lower frame rails bent and in position. Gives me a little extra to play with.

Next was the roof bar and the start of the X at the B-pillar. I raked them back some for a little extra room for my noggin. i plan on adding some tube gussets throughout the chassis.

Finished up the X the following day. Its finally starting to look like something.

Windshield bars and dash down bars were next. First iteration. Also made some axle mounts at full bump (5" of up travel). My plan is have the lower links horizontal to the ground or slightly negative at ride height. I want a ~20" belly on 43s. Last buggy was 16" and it sucked. Wheelbase is set at 112" for now. I used the center line of the belly crossmember (lower link mounts) and the center line of the axle to set the position 5" up. I used some left over spring perches and some driveshafts to set it all up. Hopefully my axles come in soon, so i can get those mounted.

 

[DirtSquirrel]

That brings us to today. Mocked up the seats to check head clearance and foot room. The down bars from the dash tube made my natural seating position very uncomfortable. It needed a change inboard.

Atlas clearance to the seat is tight.

Decided to make some outriggers out of 1.5" tube to move the down bars in a few inches on each side. Also changed them out to 1.25" diameter. Much much better seating position and a comfortable foot placement. I am going to run the exhaust out the front on the drivers side, under the crank pulley, then merge in to the passenger side. At least thats the plan.

That updates us to the end of the day. With my helmet on, i have about 2-3 fingers of head room to the roof and a full fist to the nearest tube. Without the helmet, i have plenty of room in all directions. My mockup atlas is about 1/2" off the table and i dont think i can lower it or clock it anymore.

Ive been taking my time and getting the copes as close to flush as possible. Its been a fun proces and has been a while since i built a buggy. So far so good.

Next up will be getting some upper/lower link mounts cut for the chassis side in anticipation of my housings coming in soon. Once i get those set up, i can order lower aluminum links and get the axles in position. Lower frame rails can be bent up next out of 1.5". Then i can bend the front belt/hood tubes. Its coming together.

 

[woody]

I "squished" my lowbacks in the press for a more vertical seating position and more thigh support. Also helped with headroom. The MMW case meant modifying the passenger seat rail slightly for clearance, but the mounts are on the identical plane.

Looking good

 

[DirtSquirrel]

I "squished" my lowbacks in the press for a more vertical seating position and more thigh support. Also helped with headroom. The MMW case meant modifying the passenger seat rail slightly for clearance, but the mounts are on the identical plane.

Looking good

I saw the press work you did on your PRPs. Not sure im ballsy enough to do that to mine just yet.

 

[Blase]

Great build! Glad to see you building something new and not just getting out.

I have a similar belt sander and love it! I work at a machine shop and after buying one to try at home we now have them all over the shop to polish parts. I'd call it a must have tool

What is the plan for the exhaust? Single down the passenger side? Belly looks cozy on the drivers side is why I'm asking.

 

[Ghetto Fab]

Any reason you didn't build the subframe deeper to begin with? Seems like the floor could be a couple inches higher up while still keeping the same seat position.

 

[DirtSquirrel]

Great build! Glad to see you building something new and not just getting out.

I have a similar belt sander and love it! I work at a machine shop and after buying one to try at home we now have them all over the shop to polish parts. I'd call it a must have tool

What is the plan for the exhaust? Single down the passenger side? Belly looks cozy on the drivers side is why I'm asking.

Thanks.

For the exhaust i plan on running it from the drivers side to the passenger side and merge it over there. Not sure if out the front and under the crank pulley or over the transmission. I have a couple sets of exhaust manifolds to cut up and flip around to make work. Drivers side will be just for the carrier bearing and driveshaft.

 

[DirtSquirrel]

Any reason you didn't build the subframe deeper to begin with? Seems like the floor could be a couple inches higher up while still keeping the same seat position.

I definitely could have made it deeper, and probably should have by an inch or so. Currently its about 7" top rail to bottom of the subframe. I may still cut it off and weld in a deeper one.

 

[DirtSquirrel]

No real build updates to speak of the last week or so. Waiting on my housings to come in and started trying to figure out seat mounts. Plan is to make the front mounts removable so i can take the transmission out from the top. I also cancelled my Fox air shock order with Accutune and bought a new set of 16" Radflo's from Jake at Busted Knuckle. Saved me a little money and more importantly months and months of lead times.

The real news is that i picked up a new printer for the shop.

Its a used Premier Plasma 4x4 water table with THC. Came with a hypertherm plasma and an air compressor. Time to mess with it this week and get it set up.

 

[Blitz]

No real build updates to speak of the last week or so. Waiting on my housings to come in and started trying to figure out seat mounts. Plan is to make the front mounts removable so i can take the transmission out from the top. I also cancelled my Fox air shock order with Accutune and bought a new set of 16" Radflo's from Jake at Busted Knuckle. Saved me a little money and more importantly months and months of lead times.

The real news is that i picked up a new printer for the shop.

Its a used Premier Plasma 4x4 water table with THC. Came with a hypertherm plasma and an air compressor. Time to mess with it this week and get it set up.

You need to move closer to me……

 

[DirtSquirrel]

Finally some updates. My axle housings came in from TTR after about 10 weeks (quoted a 4-5 week lead time). I was a little disappointed there. My order was exactly as ordered and missing some key parts to set up the Cs, i.e bushings to fit a stock 05+ Ford C (~2.75" inner diameter) on a 3.5" OD housing. They are apparently in the mail.

The housings are beef and the quality of the fab work is nice.

The knuckles he sent me apparently were found in the bottom of the ocean. Cleaning them up will be fun.

I mocked up the housings at full bump. Wheelbase is now 114"

A friend cut out some link tabs and weld washers and i got the front and rear lowers mocked up. They are the same length front and rear at about 40" eye to eye.

About as far inboard as i could move the front passenger lower and still have room for the bolt/nut and third member. I could maybe get it another 1/2" inboard.

I could move the rear axle mounts a little more inboard than the front about 2 more inches.

I know you cant feel a picture on the internet, but if you could, this one would melt the screen. IYKYK. Jesse Haines full hydro arms and a upper BJE welded on one knuckle.

And my one whoopsie during mockup of the lowers.

Thats it from over the weekend. I ordered some 33.5" Lg. x 2.25" dia. aluminum lowers from busted knuckle to replace the sturdy PVC. Ill continue welding on the steering arms and BJEs and start to mockup the upper mounts on the axles during the week. Then maybe get some lower frame rails bent up. Finally some progress.

 

[DirtSquirrel]

ran into another slight issue.

 

[woody]

"I only wanna turn left"

 

[DirtSquirrel]

Did a little baking last night. The bushings showed up and i got them put onto the axle ends. Turns out an hour at 500* is the ticket for it to slide over the end.

Applied the same heat to one of the SD Cs. Got it cleaned up and slid one on to the bushing. Currently its set at 4.5* of caster.

Ill try to get the others cleaned up and pressed on today.

 

[DirtSquirrel]

Finished welding the final SD knuckle this weekend and got them all painted pretty. Pressed in new lower ball joints and mounted them up with the OG Nick Barna BJ eliminators. With the unit bearings temporarily mounted, you can see how wide its going to be. I still need to redrill the pattern to 8x6.5.

Now i need to figure out this plasma table so i can get the upper links mocked up.

 

[DirtSquirrel]

Ive been messing around with the new version of the 4-link calculator to see where things end up. Thoughts on these numbers? I like have a low anti-squat in the rear and a low anti-dive in the front. I guessed on the COG number but i set it as the centerline of the camshaft. I can increase the AS/AD numbers by increasing the vertical separation of the links at the axle. Currently its at 7.5" front and 8" rear. I am seeing a lot of the new buggies with greater horizontal separation at the axles as well, so i tried to play with those numbers as well. The natural place for the upper mount to sit is the flat spot on top of the third member, so thats where i started. The front has to be somewhat wide at the axle anyways to clear the engine/exhaust/etc.

Thoughts? I know not to look too much into this, but i like numbers.

I finally sorted out my plasma table and got it cutting real nice, so new link mounts should be coming soon once i get them drawn up in cad.

 

[woody]

I wish I had a great answer on your numbers....I haven't run them on my rig, just went with what was already set.

I DO know that those numbers can vary based on what terrain you are setting your rig up for....just wish I had more knowledge on it.

 

[DirtSquirrel]

I hear ya. I know/understand just enough to make me dangerous/look dumb. I wheel the same type of stuff you do for the most part. West coast / Mason Texas crawling with the occasional oklahoma/hot springs runs.

 

[Ghetto Fab]

For street vehicles I would want to see more AS and AD, like 70%AS and 50%AD, but buggies are a different situation. My first reaction would be to go higher on your numbers, but I also know your most likely looking at very limited up travel and mostly droop with a buggy suspension so it might be ok with those numbers being low at your ride height. Then you try to factor in the extreme climb and decent angles. Lots of unknowns there.

Recently I've been looking at how to have decreasing AS with droop and increasing AS with compression. Its pretty common to do the opposite and that can lead to off camber body roll issues. Your number look good though and stay relatively flat, the AS doesn't go sky high on droop.

Your roll axis look good too. Should be nice and stable at speed. Wish I could get jeeps to look more like this!

Are your lower joints at the axle actually going to be above axle centerline?

 

[DirtSquirrel]

For street vehicles I would want to see more AS and AD, like 70%AS and 50%AD, but buggies are a different situation. My first reaction would be to go higher on your numbers, but I also know your most likely looking at very limited up travel and mostly droop with a buggy suspension so it might be ok with those numbers being low at your ride height. Then you try to factor in the extreme climb and decent angles. Lots of unknowns there.

Recently I've been looking at how to have decreasing AS with droop and increasing AS with compression. Its pretty common to do the opposite and that can lead to off camber body roll issues. Your number look good though and stay relatively flat, the AS doesn't go sky high on droop.

Your roll axis look good too. Should be nice and stable at speed. Wish I could get jeeps to look more like this!

Are your lower joints at the axle actually going to be above axle centerline?

Thanks for the good explanation. I like learning this stuff. I guess trial and error with a strong starting point is the key. That's the only way to see if this stuff actually translates to the trail. On my last rig, I had a relatively low AS/AD numbers and it did great for the most part. It had its other issues, but the suspension was dialed in my opinion and felt stable 99% of the time. Im hoping for the same.

Yes, my lowers will be 1" above axle centerline. this will have them slightly negative at ride height and hopefully not get hung up like my last one did. This made my uppers 1" higher to get the AS numbers i was shooting for. The AS numbers in the spreadsheet are pretty sensitive to vertical separation at the axle and frame. 1" in either direction and i can gain/lose 10-15% of the AS/AD values.

Im hoping having the uppers spread apart some on the axles will help with stability and reduce some body roll. I guess we will see what happens.

 

[Ghetto Fab]

Raising the uppers on the axle would have more effect on raising the roll center height, which should increase stability. You don't want to go too high with that though as I believe it really pushes the body around.

Unfortunately there are still so many unknowns and the terrain we like play on doesn't help any. Most of all the text book info out there is for a car on flat and level pavement, the best of all scenarios. Even dirt track racecars are still on mostly level ground.

I know some people like high AS and AD numbers thinking it helps to force the wheels down and into the terrain, but I prefer less and allow the suspension to be supple and the springs and shocks to do that work instead. Its important to have things balanced front to rear.

 

[DirtSquirrel]

Some small updates. The rear links are tacked into position. I copied Jake Boen's upper frame mounts as i loved the way he incorporated them into the chassis.

Rear links cut and tacked up but like a dumbass i cut them about 1.5" too short. Ill redo them.

My busted knuckle 2.25" aluminum lowers came in as well. I should have the front mocked up this week.