Snowball: the build that just keeps getting larger!!

[twiisted71]

A little pinch weld massaging helps open up room for the downpipe.

I also bought a sway bar from a ’79 Ford F150 to fit my axle. This rig is going to see lots of DD duty and I'm trying to run my suspension as pliant as I can. My '76 Bronco didn't have nor need a sway bar but it also was double shocked and had some STIFF coils on her. Hoping to get a much better on road ride out of this one. Its only 6 nuts to completely remove it if I think I'm going to need it out of the way.

Decided to set the radiator and intercooler in just to get an idea of the room I have to work with as well as inlet/outlet locations relative to the engine’s ports. The radiator is an all aluminum Griffin unit. I went with a double pass configuration since the engine’s water ports are on the same side. I can get even more efficiency from a smaller pkg.

A glimpse of those killer dual piston calipers

 

[big a]

This really is a cool build man! I'm helping my friend drop a 4bt in a bronco ii. I really like these diesels! Real nice work man!
-Andy

 

[twiisted71]

Thanks, sometimes I’m not sure if anyone is reading or getting anything out of all the drivel I’m putting up here.. Most folks who haven’t done this don’t realize that putting the engine in is the simple part! Its the little things that eat up the time and make you want to pull your hair out. Hopefully this thread can help another person considering doing a 4BT Jeep conversion. I too think these are good engines. I just wish the Kubota and Mercedes adapters had been on the market when I began collecting parts for this build. This would have been a much smaller build if so. But I'm down the rabbit-hole now......:snorkel:


Here are a couple pics to give a little perspective of how much stretch I’ve dome to the front axle. Keep in mind those are 37” tires and that DJ grill extends forward atleast 2” more than a typical CJ/YJ grill.

 

[big a]

Well, you've put a lot of info and time into this thread which is helpful! You might be surprised how much people are getting out of it! I've explored different diesel options, and with what's available, its real hard to beat the Cummins. As far as longevity and simplicity, it doesn't have an equal. I realize this may be debatable, but the only required maintenance, other than fluids, is lashing the valves. Parts are easy and relatively cheap comparatively speaking.

I'm in the process of dropping one in my 68 Bronco. I just built a shop and had to take a little break from the build, so just living vicariously at the moment

I'm enjoying your build brother! Keep it coming!

 

[Comanche Scott]

Pretty fun build to follow! You're doing a great job. :beer:
If you haven't already checked it out, 4BTswaps dot com is a great place for info.
There is a guy doing an amazing custom build of a fiberglass CJ8. Built his own frame and all.
Might have some good ideas that will work for your rig.
.
Have you given thoughts to tying the shock towers together?
.
When I swapped the 4BT into my Scout, I changed the turbo, and cut down a 6BT manifold to mount it more center and up high.
Gave a lot more room to get air out of the engine compartment, for better air flow through the radiators.
A turbo like the popular HX30 also has a slightly smaller footprint, and makes it easy to tune for more horse power without smoke or high EGTs.

 

[twiisted71]

Thanks BigA. Did you see my '76 EB on the first page of this thread? I wanted to go thaat route with this build but couldn't find a decent project base down here. I had a small mountain of rare bits and pieces from that stage of my motor-life, and have pretty much sold it all after realizing I wasn't going to do a full-on resto this go 'round. I still have a new D44 front axle housing (just in case something comes along!).


CS, yeah I've been a member on 4btswaps for YEARS (from back when it was a Yahoo site). Same screen name. I quit posting over there due to all the new dumb asses giving out erroneous advice. It just started getting to me and I decided it wasn't worth it to try to make sure folks got the "right" information. I enjoy this site much more diversity and folks who like sharing information about any and everything imaginable. Kinda like Pirate4x4 without the 'tude!
If you look back at my pics, I have a 6BT manifold I intended to use. It just doesn't want to give me enough room for A/C stuff.
Shock towers will definitely be getting a brace. That will be what my upper mounts for the Rad/IC base off. I am using an HX30, it came stock on my 4BT. I sold the HY35 seen in some pics a year ago. It was a leftover from my '01 Ram. I was one of the first folks with a P-pump motor on that site. In fact I compiled the first P7100 pump sticky there. I've talked quite a bit with most of the folks there who were "builders" and not just engine swappers. Heck that part is child's play! (You know that 1st hand)

 

[Comanche Scott]

Sorry, I meant to write "a turbo like your popular HX30..."
I'm still running the HY35, which is working fine since my first gear is so low. It's a bit big, but worked great for running the stock Dodge Air cleaner box assembly.
Your HX30 is definitely a better way to go, especially with the P Pump. :beer:
.
Here is what I was thinking of, when I was talking about room. This is from when I first got it running.

 

[twiisted71]

I'm still running the HY35, which is working fine since my first gear is so low.

Yeah I'm running a ZF S5-42 so I've got a 5.72 first gear. I've never used 1st gear with these trans in typical day-to-day driving. I'm curious to see how it will behave with 3.73s and 37" tires. I doubt 5th will be used much except on trips. Then again I very may well drop back down to 35s at some point since 37s are just so expensive and I don't know how much I'm going to like the Humvee rolling stock. That is one reason I'm not really trying to cut too many corners to make this a lightweight. I'm intentionally building heavy to help with vibes and the tire/wheel weight. I can remember how much I disliked the way 35s made my '76 Bronco feel compared to the 32s I usually ran. They were fine on my '80 Bronco but the little one went from sports car to dump truck!

 

[Comanche Scott]

That's a nice wide range box. With a 4:1 TC ratio and 3.73 rear gears, that will make for an awesome crawl ratio.
What are your plans for governed speed?

 

[twiisted71]

My TC is a NP205 so only 2:1 but with the diesel grunt and 5.72 1st gear, I think I'll be OK. I don't intend to do much in the way of technical rock crawlin!

I have a 4K GSK kit. I am going to try to get it together and get the bugs out before I start tweaking the engine though. I also have a full set of #60 valve springs. Everyone keeps saying they are only needed on the exhaust. I don't understand that as the intakes are the larger valves which in my feeble mind equals greater mass. Seems like they'd need heavier springs first to combat float at increased RPMs. I've voiced this train of thought several places and just get "Hmm, interesting."!!!! WTH! I inquired at Cummins about running increased rates on both I and E, they said it would only cost a little HP and faster wear but in actuality it would be nothing I'd likely ever notice.
Perhaps the intakes are already heavier units, IDK, but they list as the same part number so.......

 

[twiisted71]

I had roughly 1" between the fan clutch and the radiator in the pics above. Practically a canyon compared to some of the stuff I've worked on from the factory. However, I'd hate to get into some water or hit a tree or drop off a ledge and have my engine mounts flex and have some "interference clearance milling" happen:yikes:
So I removed that aluminum factory 1.5" spacer. I also slipped in the auxiliary V-belt pulley, just in case I ever needed to run "something" off it. Now I should have a full 2"+ between the clutch cooling fins and the radiator and over 3" clearance for the blades. I just cut down the studs that hold all that stuff in place. So if building something with one of these and you don't want to run electric fans, just remember that you may have one of these spacers which can be removed without too much work and gain significant space.

LOL, never noticed how grubby that fan looks. It has been stored in various places around my garage for the last couple years! Might need a little cleaning up, huh?!

 

[Comanche Scott]

Gas charge inertia has an important role in valve float. Especially at the higher drive and driven pressure in the exhaust runners.
But if it was me, and knowing how good the oil pressure is on this system, I would do both. Those valve springs bounce around like you wouldn't believe.
the only bad part of the 4BT is no cam bearings, so it is only oil pressure that staves off metal to metal contact. First start cold is where you'll get the wear... for the few seconds it takes to hit 100psi in the cam galleys. That's why Cummins says don't sweat the petty stuff, and don't pet the sweaty stuff.
.
NP 205 is a great transfer case! If you aren't rock crawling the 2:1 ratio is better anyway.

 

[twiisted71]

Yeah this isn't my first rodeo. However it is the first time I'm going to change EVERY aspect of a vehicle. So far the only stock-ish parts will be the doors and I don't know what they came off. But it had to be between CJ-7, CJ-8, and YJ!
I wanted to run a Dana 20 TC from an early Bronco on this rig but would have required a custom adapter, or so I was told. Apparently they aren't interchangeable with a NP205. They are an all iron, gear driven unit as well, just more compact and lighter. Still plenty stout for the power level I'm looking at.
I asked about downsides to using the 4K GSK vs 3K but couldn't get any hard answers. So I think I'm going to just put the 3Ks in and see if it isn't enough. Not like it is a major undertaking, esp since I can remove my fenders pretty easily.
I've often wondered about the amt of backpressure generated when guys run sequential turbos. Not like I have any intentions of having to worry about it though!

 

[big a]

Thanks BigA. Did you see my '76 EB on the first page of this thread? I wanted to go thaat route with this build but couldn't find a decent project base down here. I had a small mountain of rare bits and pieces from that stage of my motor-life, and have pretty much sold it all after realizing I wasn't going to do a full-on resto this go 'round. I still have a new D44 front axle housing (just in case something comes along!).

CS, yeah I've been a member on 4btswaps for YEARS (from back when it was a Yahoo site). Same screen name. I quit posting over there due to all the new dumb asses giving out erroneous advice. It just started getting to me and I decided it wasn't worth it to try to make sure folks got the "right" information. I enjoy this site much more diversity and folks who like sharing information about any and everything imaginable. Kinda like Pirate4x4 without the 'tude!
If you look back at my pics, I have a 6BT manifold I intended to use. It just doesn't want to give me enough room for A/C stuff.
Shock towers will definitely be getting a brace. That will be what my upper mounts for the Rad/IC base off. I am using an HX30, it came stock on my 4BT. I sold the HY35 seen in some pics a year ago. It was a leftover from my '01 Ram. I was one of the first folks with a P-pump motor on that site. In fact I compiled the first P7100 pump sticky there. I've talked quite a bit with most of the folks there who were "builders" and not just engine swappers. Heck that part is child's play! (You know that 1st hand)

Yeah, I caught that! I'm not a brand loyal person and pretty much like anything old that's not full of plastics and electronics! I don't know why I picked an old bronco to mod. I'm glad I did though because I've learned a ton, but it's been a pain staking adventure through the land of rust! Funny as most major auto manufacturers are represented in my build from Ford, to gm brakes, to bmw for the temp control, to dodge for the tranny/xfer, chevy seats, freightliner a/c brkt, etc. It's been a lot of fun. I quickly found the limits of a 2 car garage shop though

I agree! This site is great place because most want to learn or just read for the fun of it. Pirate is full of know-it-alls and 4btswaps is full of arrogance and people who forgot what it was like to learn and be new to something. Not very many friendly people over there! I pretty much stay away from there. Unfortunate really, as there are some smart people over on those sites There are more and more of these swaps showing up on other sites like here, classicbroncos and ih8mud that have knowledgeable friendly crowds!

 

[twiisted71]

I quickly found the limits of a 2 car garage shop though

Don't even get me going about that! This was a pretty "bold" undertaking in my wonderful neighborhood, where I can't even have anything outside visible! I think I spend more time kicking, straightening, and cussing than wrenching!