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BFR CH2 Buggy Build

'84 Bronco II

El Chingón
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I have been putting off starting this thread since progress is pretty slow right now, but I figured I have been starting enough threads pertaining to this build I might as well get going on a build thread.

After attending Trail Hero 2020 and riding with a buddy who has a BFR CK1, I knew I needed a buggy in my life. I started a thread about which chassis I should consider, and the BFR CH2, Goatbilt JHF 2 seater, and JHF Trail chassis were at the top of my list since they were all around $4,000 and checked my boxes (room for a V8 and a tall driver, yet compact). I ended up going with the CH2 since Tim had a killer Black Friday sale going on last year and I had been continually impressed by my buddy's CK1.

Here's the tentative build plan:

5.0L Ford
C4
Atlas or Midnight Metalworks Dana 300
'07 Superduty Axles
ORIs or 2.5" air shocks
42" Treps or 43" SX stickies

I ordered the full fixture kit and chassis-side suspension mounts from Tim and they showed up at the shipping dock the day before I was leaving to King of the Hammers. This is CH2 chassis #32:

IMG_E6017.JPG


The first thing I did was unpack everything and make sure all the tubes were there. While I was at it, I organized them and labeled them with silver Sharpie to help make the assembly go a bit easier. The laser markings are heard to see, and and the numbers make it difficult to tell where a tube needs to go without constantly referencing the BOM and assembly drawings.

IMG_6097.jpg


Tim has a few videos on Youtube showing how to assemble the chassis, as well as photo albums with comments on his Bent Fab Chassis Support! Facebook group page, and while these are good resources, it would be nice if he provided some kind of printed assembly procedures with the information on his Facebook page so that it would be easier to reference in the shop when you are putting things together. He also provides a Solidworks eDrawings model of the chassis you can use to pull dimensions from, but again, it would be more useful in the shop to have some printed drawings with the critical dimensions to reference.

Now you might be thinking my comments about assembly procedures and drawings are dumb, but this chassis is a huge pain in the ass to put together. The CNC notches and bends are spot on perfect, but you might not think so at first because the way this chassis is designed, if things are slightly off in one spot, things will be WAY off in another. It is like a game of Whack-A-Mole trying to get everything to fit up perfectly, and you basically have to assemble the ENTIRE chassis before you can get to a point where you can even put down your first tack :eek:

There are many locating holes/marks that indicate where tubes are supposed to land on each other, but they are not there for every joint. Some places are no big deal, but just a few more marks/holes would literally save hours on the assembly time. The most frustrating part where location marks would have been a massive help were where the seat tubes meet the rub rails. There is no indication on the rub rails where the seat tubes should go other than eyeballing the front seat tube being in the middle of a bend on the rub rail. The way the chassis is designed, being slightly off here has a huge impact on how everything else fits together since small changes in seat bar placement rolls the rub rails in or out drastically, and there isn't anything to hold the rub rails even with each other longitudinally. You can use one of the A-pillar support tubes that has locating marks and a very slight cope for the forward seat bar to help locate it on the rub rail, but it is not very precise. Even with the full fixture kit, you are definitely going to want someone else helping you. I cant imagine trying to put the chassis together on my own.

The critical first step:
IMG_E6099.JPG


Speaking of the fixture, it is poor design that isn't really that helpful. In fact, I found it to be more of a hinderance since I was fighting it when putting the dash, seat belt, and roof bars in place. Part of the problem is that it doesn't do much to locate the tubes, it just kind of floats a few of the lateral bars in roughly the correct place. The way the upper part of the fixture is designed, it is very prone to assembly shift making relying on it for accurate location of the tubes impossible. Also, the cutting parameters on Tim's plasma table could also use some fine tuning because almost all of the notches for the tubes were undersized and required some work with a 1.5" sanding drum to get the tubes to nest in the notches like they are supposed to. I had read another build thread about bolt hole sizing being an issue with Tims parts, and while Tim assured me the issue had been fixed, it appears to still be an issue (although to an admittedly lesser degree). I only had to re-drill one or two holes on the fixture, but all of the holes are stupid tight for the intended fastener size; like you have to thread the bolts through the holes. On the suspension brackets, you can get threads through the holes, but the unthreaded shank on the bolts don't fit through the holes :shaking: The bed rail part of the fixture wasn't even close to the correct size and I didn't use it at all. If I were going to do it again, I would just buy the base that spaces the seat bars and the spreader for the front of the rub rails.

IMG_6266.JPG


IMG_6267.JPG


IMG_6270.JPG


I don't mean to sound like I am bashing Tim, but he has some persistent quality issues that need to be addressed and I want others who are considering buying from him to know what to expect.
 
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Here are the Modular rear suspension mounts going together. Tim ships the flat and you bend the pieces so that they fit together. I found using a cutoff wheel to cut ~75% of the the way through the metal at the ends of the kerf allowed for much sharper bends that you could do with your hands the make the iterative fit and check process a bit quicker. I used all-thread to to hold the spacing for the joints at 2.660" so that the joints would slide in easily after welding.

IMG_6302.jpg


Welded out. There is an additional plate that boxes in the bottom of the lower mount that I welded on after I welded the mounts to the chassis.
IMG_E6309.JPG


The tear drop weld washers for the lower mounts don't fit if you weld them directly inline with the angle the link will be at so I rotated them up and welded them in like this:
IMG_6321.jpg


Here are the rear modular mounts getting welded onto the chassis with the gusseting that is supplied with them
IMG_E6363.JPG


Tim designed these brackets with the slotted hole on top for mounting a Cherokee radiator. Does anyone have experience cooling a V8 with a Cherokee radiator? I like how low they are so that you can see over them, but I am not sure how they do trying to keep a 300-400HP V8 cool in triple degree desert heat.

Since my rear uppers were 2 5/8" wide with a 3/4" bolt hole, I decided to drill out the upper tabs for the front to a 3/4" hole figuring I could use the same size hardware at all of the link mounting locations.
IMG_6323.JPG


Unfortunately, this is were I ran into a small issue. I am planning on running 7/8" upper joints, but no one makes 2 5/8" wide 7/8"x3/4" high misalignment spacers and despite Tim stating that his upper mounts are compatible with 1" x 1 1/4" joints, they aren't really.

Plenty of room for a 7/8" joint:
IMG_6324.jpg


The front upper tabs are too short for 1" x 1 1/4" joints, so the joint hits the tube:
IMG_6325.jpg


The top position of the rear uppers does not clear the bigger joint either (although it wouldn't be too hard to modify to fit), but the middle and lower holes clear fine. Tim tells me that the rear uppers are intended to be run in the middle hole.
IMG_6327.jpg


I will keep the 2 5/8" spacing for the uppers and run some 2.5" wide high misalignment spacers for 7/8" joints with some 1/16" shims to fill the gap. Even though I do not intend to run 1" x 1 1/4" uppers, I want the ability to if I should want to in the future, so I bought some longer tube tabs from TMR while I was ordering some axle brackets. I decided to cut the BFR upper tabs down to tear drop weld washers since they were not included for the front mounts, even though all of the holes for the rear mounts had weld washers :confused:

IMG_6368.jpg
 
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Always liked his chassis designs. Looking forward to seeing another one of these completed. Bummer there are so many little issues.

When/why did he go away from the square tube sub fame?
 
You are getting hung up on some tiny details that don't make a lot of sense to me.
But I'm glad to see another CH2 put together and I wish you well in the build process.



Also,

img_6171-jpg.548822


Told you the EVO was bigger.

Always liked his chassis designs. Looking forward to seeing another one of these completed. Bummer there are so many little issues.

When/why did he go away from the square tube sub fame?
Lining up and locating the square frame rail would be a pain for most garage builders IMO.

Tim's chassies are some of the best looking ones out there. I'm biased, but the man is very talented and creative when it comes to design.
 
Always liked his chassis designs. Looking forward to seeing another one of these completed. Bummer there are so many little issues.

When/why did he go away from the square tube sub fame?

Nothing too major; honestly I knew what to expect after reading Scotty Mac's build thread, but the fixture gave me some heartburn. I assume easier manufacturing and shipping on the frame rails, but neither the CK1 or CH1 had rectangular frame rails. The subframe went together super easy on this chassis, but I can see the overall assembly going together easier with rectangular rails and was one of the things I liked about the Goatbilt JHF chassis.

You are getting hung up on some tiny details that don't make a lot of sense to me.
But I'm glad to see another CH2 put together and I wish you well in the build process.



Told you the EVO was bigger.


Lining up and locating the square frame rail would be a pain for most garage builders IMO.

Tim's chassies are some of the best looking ones out there. I'm biased, but the man is very talented and creative when it comes to design.

I'm not really getting hung up on the little things as much as just pointing them out for folks who might be considering one of these chassis. The problem when I was shopping around for chassis is that it is hard to find people with the chassis you are considering to sit in them and "try them out." Also, ease/speed of assembly is the whole reason people buy chassis kits instead of just building their own which would be a lot cheaper, albeit much more time consuming. I think it is worth talking about how the kit goes together and showing any problem areas rather than showing a pile of tubes and then an assembled chassis and saying "Look at my awesome chassis guys!"

I know the EVO is bigger, but I wanted a compact chassis for what I plan on doing. I knew going into this it was going to be tight and the Goatbilt JHF chassis has much more leg room. Frankly though, Tim could easily move the rear seat tube back 1-2" and give more legroom without affecting the aesthetics or functionality of the chassis.

I agree, I like the aesthetics of Tim's chassis, and I think he has some really good designs and innovative ideas, but my experience as well as others who have worked with his chassis is that the details leave something to be desired.
 
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^^agreed... pointing things out on a line by line basis is great for someone who might be looking into what it would take to buy, then assemble one of these kits. You don't see too many write ups like this... the thing is, seeing the difficulties that one has to overcome while building a kit chassis may just help a person decide whether they should take a project like this on or not. It could potentially save someone tons of wasted time and money IMO
 
I am building a Goat JHF with a 5.0, still working out if I am going C6 or C4. Curious to see what C4 adapter, and what intake configuration you are planning.
 
I am building a Goat JHF with a 5.0, still working out if I am going C6 or C4. Curious to see what C4 adapter, and what intake configuration you are planning.
I would take a look at valve bodies, when i was looking for my C4 reverse VB it was a nightmare to find for the year of my trans and w/o a indefinite wait, I ended up buying a cheap later C4 and found a VB on summit but they've since gone out of stock as well
 
I am building a Goat JHF with a 5.0, still working out if I am going C6 or C4. Curious to see what C4 adapter, and what intake configuration you are planning.

I am going to be running an Explorer GT40 intake and serpentine setup. The GT40 intake is the best balance of low end and top end power on an EFI Windsor factory or aftermarket and is low profile. The Explorer serpentine setup is also the most compact factory setup and has nice cast aluminum brackets that with some slight modification will accommodate a CBR pump.

If you get a 4WD C4, you can get an Atlas that will mate to the factory tail housing. I am going to use Advance Adapters PN 50-2905 since it is super short and I am converting a 2WD tranny anyway. I would suggest going with a C4 over a C6 in a crawler because the are a lot smaller and lighter, and can easily be built to hold up to a healthy V8. Dynamic has a 2.9:1 gear set for the C4 too, I don't know about low gear sets for the C6.

I would take a look at valve bodies, when i was looking for my C4 reverse VB it was a nightmare to find for the year of my trans and w/o a indefinite wait, I ended up buying a cheap later C4 and found a VB on summit but they've since gone out of stock as well
I recently had a C4 built for my race Bronco, and Dynamic has both reverse and forward pattern full manual valve bodies. The 1970+ transmissions have much better support than the '64-'69 versions, but the early ones still have decent support due to all the vintage Mustang guys.
 
Just nitpicking here, but it's very important.


img_6265-jpg.548824



That node.

Those two side tubes that are at a 45* angle need to be welded out before that vertical piece gets set on top of them. You want each tube welded 100% before it's covered by another tube. Even if you have to break some tacks on whatever those three tubes run up to, so you can move it and allow you to reinstall the vertical center tube after the angled ones are welded.

Hope that makes sense.
 
Just nitpicking here, but it's very important.


img_6265-jpg.548824



That node.

Those two side tubes that are at a 45* angle need to be welded out before that vertical piece gets set on top of them. You want each tube welded 100% before it's covered by another tube. Even if you have to break some tacks on whatever those three tubes run up to, so you can move it and allow you to reinstall the vertical center tube after the angled ones are welded.

Hope that makes sense.
I get it, but nobody does it that way.
 
I get it, but nobody does it that way.
That's not true.

All of my nodes are fully welded on my current buggy. I guarantee any pro built chassis is as well. In SFI drag car manuals they actually call that out as necessary.


I'll be watching this build. I like the BFR chassis and am enjoying how many buggy builds seem to be going on over here currently.
 
That's not true.

All of my nodes are fully welded on my current buggy. I guarantee any pro built chassis is as well. In SFI drag car manuals they actually call that out as necessary.


I'll be watching this build. I like the BFR chassis and am enjoying how many buggy builds seem to be going on over here currently.

The cage I put on my SxS is done like that also, but 80% of the chassis out there in any form of motorsports are not. High end stuff more than likely is, run of the mill chassis that get built by the dozens, absolutely not. I've cut apart enough circle track chassis in my lifetime to know this first hand.


Anybody got a picture of one of these "unfinished" nodes broken after a crash? I can't recall ever seeing one...
 
The cage I put on my SxS is done like that also, but 80% of the chassis out there in any form of motorsports are not. High end stuff more than likely is, run of the mill chassis that get built by the dozens, absolutely not. I've cut apart enough circle track chassis in my lifetime to know this first hand.


Anybody got a picture of one of these "unfinished" nodes broken after a crash? I can't recall ever seeing one...
I got you, I was just responding to your "nobody does it that way." I think that you are right in that most rec wheelers that are never going to see a highspeed roll will be fine, and lots of rec buggies aren't welded out but it is certainly not all of them, and that doesn't make it best practice or correct.
 
I get it, but nobody does it that way.

Anybody got a picture of one of these "unfinished" nodes broken after a crash? I can't recall ever seeing one...


I was hopefully trying to avoid having something to take a picture of.:flipoff2:

It does make a stronger node.

I understand that many home builders might not know to do it. Or don't care. And it's certainly not instant death. I just figured at the tacking stage, it might be a good habit to get into.

Anyone who builds cages for a living that doesn't do it should be fired.
 
Tim designed these brackets with the slotted hole on top for mounting a Cherokee radiator. Does anyone have experience cooling a V8 with a Cherokee radiator? I like how low they are so that you can see over them, but I am not sure how they do trying to keep a 300-400HP V8 cool in triple degree desert heat.

I would not go that route. They are wide, get a normal Ron Davis and lean it back if you need to, towards the engine.
 
Plenty of width in a CH2 to mount an XJ rad. Has been done many times.

I would not go this route because they are too small for a V8, not because they are too wide.

31x19 with Spal twin 14" fans from any good rad manufacturer is what I would do. It will fit no problem in the CH2.
 
Got a build thread?

Negative, but almost ready to start on it. Probably be months before I would have anything worth sharing.

I would suggest going with a C4 over a C6 in a crawler because the are a lot smaller and lighter, and can easily be built to hold up to a healthy V8. Dynamic has a 2.9:1 gear set for the C4 too, I don't know about low gear sets for the C6.


I recently had a C4 built for my race Bronco, and Dynamic has both reverse and forward pattern full manual valve bodies. The 1970+ transmissions have much better support than the '64-'69 versions, but the early ones still have decent support due to all the vintage Mustang guys.

My girl's Ranger truggy has a rollerized C6 with a Broader performance RMVB, works absolutely perfect. C6 can be upgraded with a wide ratio planet from E4OD, and is definitely cheaper/stronger and with no custom adapters. I don't think I want to be as short as you are planning, but once I get the motor placement down I will know for sure.
 
Just nitpicking here, but it's very important.

That node.

Those two side tubes that are at a 45* angle need to be welded out before that vertical piece gets set on top of them. You want each tube welded 100% before it's covered by another tube. Even if you have to break some tacks on whatever those three tubes run up to, so you can move it and allow you to reinstall the vertical center tube after the angled ones are welded.

Hope that makes sense.

Calm down, I was just tacking stuff together in that picture and not welding it out :flipoff2:

I tacked everything together before I started welding it out so things wouldn't move on me. I then cut tubes back out basically one or two at a time to fully weld the tubes at the bottom of the joint. After that, I feathered the copes/weld to put the supporting tubes back in and weld them afterwards (what is actually going on in the picture just above the one you quoted :laughing:). However, There were a couple spots where I wasn't able to do that without cutting tubes apart and welding them back together :barf: Maybe poor planning as far as order of welding operations, but those few joints were really tight, so it might not have been avoidable regardless.

Something to think about, even without fully welding the covered joints, every tube still has 360º of weld around it. There is also a ton of weld area around the joints, which without putting a pen to paper, should be stronger than the tubes themselves. I do not think it is really that necessary to kill yourself trying not to have and un-welded covered joints, but I also think it is good practice to weld the covered joints when possible. I see welding the covered joints more as insurance against less-than-perfect welds on the visible joints.

It is an interesting enough topic that I might dive into it and do some modeling when I have some free time at work sometime. As far as my chassis is concerned, we are past the point of this debate, but I'd say it is about 90% welded out the way you describe (The entire front of the chassis is).

The cage I put on my SxS is done like that also, but 80% of the chassis out there in any form of motorsports are not. High end stuff more than likely is, run of the mill chassis that get built by the dozens, absolutely not. I've cut apart enough circle track chassis in my lifetime to know this first hand.


Anybody got a picture of one of these "unfinished" nodes broken after a crash? I can't recall ever seeing one...

ˆˆˆ THIS

gt1guy (or anyone else) If it is such a poor method of welding a chassis/cage out, please report to the Roll Cage Thread with some pictures of failures and we can continue the discussion there. I would be genuinely interested to see some proof, so I can feel better about all the time I wasted welding the covered joints on my chassis :flipoff2:

I was hopefully trying to avoid having something to take a picture of.:flipoff2:

It does make a stronger node.

I understand that many home builders might not know to do it. Or don't care. And it's certainly not instant death. I just figured at the tacking stage, it might be a good habit to get into.

Anyone who builds cages for a living that doesn't do it should be fired.

Strong words; I'd like to see evidence for why it is the "right way" and people who don't do it that way are hacks that should be fired. Again, report to the Roll Cage Thread to avoid derailing this one if you wouldn't mind.



I would not go that route. They are wide, get a normal Ron Davis and lean it back if you need to, towards the engine.

Plenty of width in a CH2 to mount an XJ rad. Has been done many times.

I would not go this route because they are too small for a V8, not because they are too wide.

31x19 with Spal twin 14" fans from any good rad manufacturer is what I would do. It will fit no problem in the CH2.

Thanks for the feedback and confirming my suspicions that an XJ radiator wouldn't cut it.
 
Negative, but almost ready to start on it. Probably be months before I would have anything worth sharing.



My girl's Ranger truggy has a rollerized C6 with a Broader performance RMVB, works absolutely perfect. C6 can be upgraded with a wide ratio planet from E4OD, and is definitely cheaper/stronger and with no custom adapters. I don't think I want to be as short as you are planning, but once I get the motor placement down I will know for sure.

It would be interesting to see how a SBF fits compared to the LS and TH350/400 that a lot of people go with.
 
I'm calm. Wasn't trying to start shit. You have a great build going on there. Just thought I'd point it out.

To be honest, I hope the roll cage failure thread says small and never has new pictures to add.
 
It would be interesting to see how a SBF fits compared to the LS and TH350/400 that a lot of people go with.

I know you quoted Satan's_Minion, but I figured I would answer you since size and weight was part of my consideration between LS vs. Windsor even though I am a bit of a Ford guy. HP/$ is no contest, the LS wins there. The short deck Windsors (260, 289, 302, etc.) have a 4.38" bore spacing which is basically the same as the 4.4" in the SBC and LS, but the deck height is only 8.2" which makes it shorter and narrower than an LS which has a deck height of 9.2". Late Windsors have thin wall block castings (the reason for the "500HP limit" commonly parroted on the internet for 5.0Ls), and with aluminum heads, intake, and water pump, they weigh about the same as an all-aluminum LS which are rarer and cost a lot more than the dime-a-dozen LM7 5.3Ls that most people use. The Explorer 5.0L is distributorless and has the best factory Windsor heads Ford ever made (Boss 302 excluded because those were really Cleveland heads on a Windsor block A.K.A. a factory "Cleavor"), and an almost identical intake to the Cobra and Lightning intakes which are the best factory EFI intakes. With a cam, an Explorer 5.0L will easily make over 300HP. and about 330HP is possible without expensive aftermarket heads or stroker kits (comparable to a stock 5.3L). If you want 6.0L power, you are going to need a stroker kit and aftermarket heads along with the cam; although, If you want 6.0L power, you are better off using a 351 which can easily go over 400ci, but then you have a 9.5" deck height, so you no longer have a size advantage, and you lose pretty much all of the weigh advantage over an iron block LS.

The headers on my buddy's LQ4 in his CK1 (very similar chassis to the CH2) BARELY clear his upper links. I should have a good bit more clearance with a 5.0L. He is also running a TH400 which is about 40 Lbs. heavier and 6-9" longer than a C4 depending on which tail housing you go with. His engine and transmission combo is about 100Lbs. heavier than mine will be (with a higher C.G.), and I will be able to set my engine further back if I want.

I'm calm. Wasn't trying to start shit. You have a great build going on there. Just thought I'd point it out.

To be honest, I hope the roll cage failure thread says small and never has new pictures to add.

I am just giving you shit, not upset at all. I am all for technical discussion, it just seemed like things were primed to take this thread off the rails. I agree on the size of the roll cage thread, but unfortunately you learn a lot more from things that don't work than things that do.
 
Not a whole lot to show for this last weekend, but I drilled out the TMR tabs and tear drop weld washers to 3/4", finished welding out the front chassis suspension mounts, and started mocking up drivetrain. I also ordered suspension joints. I ended up just getting 1"x1.25" joints for the uppers and lowers since the cost difference was negligible and that solved the issue of the upper rear suspension brackets being 2.625" wide with a 3/4" bolt hole.

The gusset plate for the front lower mounts is wider than the belly and the ends need to get bent to to tie into the subframe supports. I cut into the plate with a cutoff wheel like I did with the modular suspension brackets to make it easier to form.
unnamed-3.jpg


Here are the front suspension brackets welded out with the original BFR upper tabs turned into weld washers and the longer TMR tabs spaced for a 2.625" joint using the BFR gusset plates. It looks kind of shitty because the cheap wire I bought is supper sooty and splatters a lot despite all the metal being cleaned off with a stripper wheel and acetone :shaking: I might need to try switching back to some brand-name wire to make sure I am not crazy. I am debating whether I should box in the top of the lower mounts.

unnamed.jpg


I need to figure out something to hold the engine in place while I come up with a way to mount it. I guess it is time to pony up for a transfer case...

unnamed-4.jpg
 
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It looks kind of shitty because the cheap wire I bought is supper sooty and splatters a lot despite all the metal being cleaned off with a stripper wheel and acetone :shaking: I might need to try switching back to some brand-name wire to make sure I am not crazy

My local welding supplier has recently dropped all their off brand welding wire for this reason. Lots of complaints of shitty welds and wire that has bad splices in the spool causing birds nests
 
I would wait until you have the TCase before you try to install the engine.
 
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