dura-pig? durpig?

[ericjon262]

I had found myself wanting to work on the firebird, but when I realized the LB7 and GMT800 chassis were taking up most of the space in the garage, I realized it would be significantly smarter for me to get the ball rolling on a vehicle that doesn't move, rather than one that does, so I started making swift progress.

it was a bittersweet moment, my plan of mounting the suburban body on the GMT800 chassis could have worked, but I would have needed to modify the body mount positions on the body, the chassis side would need to be made completely over again, all things which I am more than capable of handling, it would have been cool to have the chassis built and have something that unique, however, every time I looked at it the project snowballed a little more, and it was starting to feel like if it got done, there would be compromises I wasn't happy with, so today, I liberated the A1000 and LB7 from the chassis, along with what was left of the wiring harness, and removed the chassis from the garage.

after that I went out to the C20, and started working on getting it pushed and/or pulled into the driveway so I could blast the funk off of it, and then into the shop, this became a nightmare, apparently the key I thought I had for it was not in fact the correct key, after a couple of hours of messing with it, I was finally able to get the lock plate out of the column, and the transmission out of park. Since I need a new ignition cylinder now, I'll try and see if I can get one keyed to match one of the other cars in my fleet. but it's in the shop now, which is a massive win IMO.

then I started on research, I have a complete LB7, and a basket case LBZ, the LBZ is considered far more desirable, for a couple of reasons, VGT turbo provides a broader power band, and the injectors are typically more reliable, and more easily replaced. I would long term, prefer to use the LBZ parts, or even the whole engine instead of the LB7 parts, and some quick questions are facebook tell me that I can run the LBZ parts on the LB7, but i'll need to swap to the LBZ crankshaft reluctor, FICM, ECU, and 6 Speed Allison, so i would also like to try and make sure my wiring and other infrastructure can accommodate both systems to the max degree possible,

Engine mounts quickly became a sore subject for me, my original plan was to cut the GMT800 engine mount ears off of the chassis and then weld them onto the C20 Chassis wherever they need to go, however, it appears the geometry of the driver's side mount won't really work that easily. There are aftermarket mounts available for the swap from Precision Fabrication, but their price is bonkers, $764 for just engine mounts, and that doesn't include a matching transmission crossmember... if I didn't have access to a machine shop, and a CNC plasma cutter, this route would make more sense, but to get the full kit with a trans crossmember is over $700 more, and I just can't do that, so it looks like I'm more or less on my own. My current plan, is to measure the distance of the bellhousing to the firewall on the 454 prior to removal in several spots, then map the locations of the engine mount bosses on the 454 and LB7, then determine how far I need to move the bellhousing forward to clear a turbo downpipe, and then make mounts based on that.

I'm probably going to remove the front clip from the suburban prior to trying to removing the 454, my shop doesn't have much vertical clearance, and the lower I can keep an engine the size/weight of a duramax, the better.

I plan on adding a lift pump, and a A2W intercooler, I plan to try and make both run anytime the engine is running, and I imagine the lift pump supplier will have directions on how to do that easy enough.

[ericjon262]

I traced out the mount pattern on the duramax block.







next step is to take measurements from the bellhousing to the mounts on both this engine, and the 454, I imagine I will need to offset the bellhousing further forward to make room for the downpipe to fit.

in other news, a guy on facebook offered to trade extension housings with me, that will make my 4x4 A1000 into a 2WD A1000

I took my extension housing off today in preparation for sending it off, and also pulled the pan, I was not stoked about what I found...

the valvebody looked fine, there was a thin later of wear products on the filter, the light gray area is where I sprayed it with brake clean.



pan magnet had material on it, but not really enough to scare me.



but the pan itself had some nasty sludge in it, nothing gritty, but it's it doesn't give me warm fuzzy feelings, looks almost like water intrusion to me.



I found this video detailing an A1000 rebuild, there's a few transmissions available local to me, I might install this one, since it did drive around the yard fine, and then pick up another to rebuild, and maybe do some low effort modifications to for improved reliability. Based on this video, and the little bit of work I've done on this transmission, it doesn't seem too hard.

https://youtu.be/lUBD5_D_Iw0?si=PG4GI__cTS7iRJg0

I'm going to try and make some plates to help me get the bellhousing measurements this week, and hopefully make some headway on this in my small amounts of spare time.

[ericjon262]

in other news, a guy on facebook offered to trade extension housings with me, that will make my 4x4 A1000 into a 2WD A1000

I finally got around to getting this packaged and ready to ship, UPS wanted $470+ to ship the tailhousing... ! I looked on marketplace and there are several examples of 2wd A1000 cores for about that or even less, so I decided it wasn't the best path forward and am looking into picking up another A1000, ideally a 6 speed from a later model truck, although this would also require a TCM, or at a minimum calibration of the 5 speed TCM.

[ericjon262]

I was able to sneak some garage time today, I stripped the 454 down, carb, distributor, exhaust manifolds, accessories, radiator, and a few other odds and ends have all been pulled, it's ready to pull with the exception of the bellhousing bolts, the torque converter bolts, the oil cooler lines, and the motor mounts, but I'm thinking I'll start by pulling the trans, and then get the engine out.

Crap picture, but you get the idea.



also, found some useful pinouts I would like to find actual diagrams too though.










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[ericjon262]

Today I learned that California emission equipped LB7 Duramaxes have a engine driven vacuum pump, it's a possible option for the vacuum HVAC controls.


GM PN 12562793

https://www.oreillyauto.com/detail/c/se ... 0-hd?pos=2

otherwise I'll be looking into a electric pump, which isn't a big deal. seems like people tend to recommend early 2000's F250 vacuum pumps, its a self contained electric pump, IGN+ and ground, and it does everything itself. it's also pretty cheap. if I go that route, I'll add a small reservoir to help with transients.

PN 6C3Z2A451A

[The Dark Side of Will]

Today I learned that California emission equipped LB7 Duramaxes have a engine driven vacuum pump, it's a possible option for the vacuum HVAC controls.


GM PN 12562793

https://www.oreillyauto.com/detail/c/se ... 0-hd?pos=2

otherwise I'll be looking into a electric pump, which isn't a big deal. seems like people tend to recommend early 2000's F250 vacuum pumps, its a self contained electric pump, IGN+ and ground, and it does everything itself. it's also pretty cheap. if I go that route, I'll add a small reservoir to help with transients.

PN 6C3Z2A451A

Diesel GMT600/610 vans have a vacuum pump + reservoir that only drives the HVAC mode servos.

Vacuum Pump:
https://www.rockauto.com/en/moreinfo.ph ... 2&jsn=1046

Vacuum Reservoir:
https://www.rockauto.com/en/moreinfo.ph ... 7&jsn=1074

Some idiot on Rock filed the vacuum pump under "Brake & Wheel Hub" and the vacuum reservoir under "Exhaust and Emission", but they're really installed purely and solely to operate the HVAC.

This pump will *NOT* operate power brakes, but I assume you have a hydroboost for your truck.

[ericjon262]

Diesel GMT600/610 vans have a vacuum pump + reservoir that only drives the HVAC mode servos.

Vacuum Pump:
https://www.rockauto.com/en/moreinfo.ph ... 2&jsn=1046

Vacuum Reservoir:
https://www.rockauto.com/en/moreinfo.ph ... 7&jsn=1074

Some idiot on Rock filed the vacuum pump under "Brake & Wheel Hub" and the vacuum reservoir under "Exhaust and Emission", but they're really installed purely and solely to operate the HVAC.

This pump will *NOT* operate power brakes, but I assume you have a hydroboost for your truck.

good info, and I don't have one yet, but I am planning on picking up a hydroboost setup, they're pretty inexpensive.

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not a whole lot to report, last update I had stripped the engine down, this update the transmission is out! a guy is supposed to be picking it up in the morning, which should complete the funding for my 2wd A1000.
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[ericjon262]

I got off work tuesday morning, and then yanked the 454 out.





Next, I want to hose down the engine compartment with purple power and the pressure washer as much as possible, I want to make it as clean as I can so that I can put a little paint down and make it very nice. I'm thinking I might apply Monstaliner to the firewall and floor pans to protect it as much as possible.

It's a shame the 454 had such a horrendous knock, it was super clean, at least under the valve covers.

[ericjon262]

I spent some time today cleaning up the truck, I pressure washed the engine bay, and then removed a bunch of stuff from the engine bay the coolant bottle, the washer bottle, the jack and jack accessories ect.

I need to give serious consideration towards engine mounts, I found these, and like them alot, I'll probably buy a set, and develop plates so they can bolt to the squarebody crossmember,

https://www.merchant-automotive.com/Dur ... -2001-2010

I'm planning on pulling the hood and core support, maybe tomorrow, so that I can work on test fitting the duramax, I really don't want to pick the DMAX up high enough to clear the top of the core support, it's a heavy SOB.

[ericjon262]

I ordered a bunch of parts tonight...

Merchant automotive mounts for the engine
GMT400 Accelerator pedal position sensor
Hydroboost
and the vacuum pump will linked to, thankfully, I have a vacuum reservior already, so I was able to save a few bucks there.

this morning I started pulling everything off/out of the engine compartment, I have several holes in the firewall I'll need to patch up, there were several wire pass throughs, when I'm finished, hopefully there will only be one or two in the corner by the C100. I also got the majority of the exhaust removed. in the morning, I would like to get the hood off, and if all goes well, hopefully the fenders and core support too so that when the mounts show up, I can hop to and get the engine in place. and finalize the mounts.





I finally picked up a 2wd A1000, the guy claims it's a good transmission, I'm not sure which of the two I want to trust, I'll pull the pan on the one I picked up today and see how it compares to the one I had, if it's significantly cleaner, I'll give it a shot, otherwise I'll swap the tailhousings and call it a day. it also appears as though a1000's are all fixed yoke, which is kind of a bummer, I would rather not have a 2 piece driveshaft.

[ericjon262]

I pulled the rest of the front clip yesterday when I got off work, I'll probably try and get everything pressure washed again so that all the stuff that was covered up gets nice and clean. While i don't plan on repainting the whole truck anytime soon, I would like to make sure I get as much of the engine bay cleaned, painted, and looking good now, so that if I paint this thing, it looks great all over when I'm finished.

[ericjon262]

One of the big picture plans I had for this truck, was to bring over the disc brakes from the donor chassis, to keep things happy, I planned to also bring over the donor truck master cylinder. I had already attempted bolting the GMT800 hydro boost to the 86 body, it doesn't work, or at least not directly. so I ordered a hydro boost for a 86, and bolted it to the firewall.

well, we'll see how this works...




Well, it doesn't... that's kinda a bummer, the biggest master cylinder I could find for a squarebody is 1-5/16", the GMT800 master is 37mm, or almost 1-1/2", WAY bigger than the biggest squarebody master. so I'd like to figure out how to make the GMT 800 parts work, and I would like to make as much of this a bolt on as I possibly can, so lets explore the differences between the boosters.

obvious differences first, the studs are inverted between the two, and a different pattern. The pushrod from the pedal to the booster is also a drastically different length.



now a not so obvious difference. the rear portion of the booster is different, the GMT800 is slightly larger than the squarebody. you probably can't see the difference, but what you can see is a rib cast in the squarebody booster that's not in the GMT800.



I took some measurements, and the nut that holds the booster to the backing plate appears to be identical. there's also a snap ring behind the nut, I guess to act as a backup to the nut? I took the snap ring off one of the boosters, and it didn't appear to do much of anything.



My immediate thought, is that I can swap the backing plates and the pushrod, and it should be a bolt on. The issue with that, is the pushrod is staked to the booster, I'm not sure how destructive removal of the pushrod is yet, I would hate to have the pushrod fall out driving down the road, so I need to explore safe removal and reinstallation before I continue down that path.

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Motor mounts... last week I made an important discovery with relation to the motor mounts. On the suburban, the motor mounts are directly across from each other, on the Duramax, they're actually offset from one another, by a not significant amount, so I'll need to explore ways to remedy that problem, I would like to get a good 3d scan of the engine and chassis, it would let me mock things up quite a bit easier.

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Vacuum pump arrived for the HVAC, I already have a bulb that was on the truck for cruise control, so I'll reuse that. I need to do some testing to see if the pump based on the wiring diagrams, it appears as though the pump is entirely self contained from a controls perspective, which will simplify wiring. I plan to integrate the vacuum pump wiring with the body side wiring so that if I ever pull the body off of the frame, it's one less thing I will need to disconnect.

[ericjon262]

I was considering how to make the hydroboost work, and I came up with what I think is a reasonable method,




What you see is an adapter that adapts the small bore of the squarebody booster to the larger diameter of the GMT800 master. The big perk of this method, is that an off the shelf booster, and a off the shelf master can both be used, unfortunately, this will require a custom length pushrod, but that's an easy enough task to fab up. I could also install a support bushing in the adapter to ensure the pushrod doesn't bend, but I don't thing that would be necessary.

The other obstacle, is that the studs that hold the master cylinder on would probably be too short now. but they are also literally bolts, I could get some high strength all thread, run it through, put a nut on the backside and peen the threads. it wouldn't be pretty, but it should work ok, and I would be the only one to really know.

[ericjon262]

I hadn't had a chance to mess with the brake boosters in the past week, but I think I have 2 options ATM.

one, use the stock squarebody booster with an adapter for the master

Two, adapt the GMT800 booster.

Either option sounds easy, but gets more and more complicated the longer it's thought about, the pushhrod for the GMt800 booster is too short and staked onto the booster, and the studs on the Squarebody booster aren't long enough to go through an adequate adapter and the master. I've got an idea in my head for a bolt on pushrod extender, which makes the GMT800 work with a firewall adapter plate. but t's also worth mentioning the GMT 800 and Squarebody boosters bolt to the firewall at different angles. so the adapter would end up a little more complicated than just a flat piece with 2 bolt patterns drilled in it, and because the boosters mount at different angles. if I get some time this weekend, I'll sketch a few ideas up.

[ericjon262]

I had a bunch of holes in the firewall that will no longer do anything useful, so I made some filler bits, and welded them all up. The goal was to no longer have holes, I'm not trying to make a show truck, I could have put more effort into smoothing the patches out, but most of them will be behind the engine, or not really visible anyways, additionally, I'll be painting the firewall with monsta liner, and I suspect the texture will hide most imperfections.









I shot some black paint on it, you can see some imperfections, but again, it will all be behind an engine, and covered with monsta liner.



I would like to test fit the engine tomorrow, but I also have work tomorrow night, so I may just take the seats and console out in preparation for transmission tunnel modifications.

[ericjon262]

I pulled the interior out of the front, the front seats, center console, and carpet are removed, next I need to cut the trans tunnel, and find a more or less complete "high hump" floor section so I can fit the A1000 under the floor.

I did a test fit of the engine with some adapter plates that should make the stock SBC/BBC mounts fit, unfortunately, they didn't really work very well, with one mount loosely held in place with 2 bolts, the other is over 1-1/2" off. At this point, I plan to take measurements off of the truck, and then measure the brackets, and use those measurements to develop a mount system that sits in the stock cushions.

the way I want to do this may also require me to modify the center link for the steering, at present, it's extremely close to hitting the oil pan, and I suspect that once the engine is where I want it, they'll occupy the same space. because the centerlink isn't really a wear part on this truck, I'm ok with making modifications, or making one, the idea currently is to use some beefy tubing and bend a dip into the center link so it goes below the pan, but overall maintains the same geometry. my only current issue, is that I don't have material, or a bender... I might just have one made so I don't have to, maybe call up ORD or someone.

I'll try and post up some pictures tomorrow.

[ericjon262]

Pics as promised, note I didn't promise good pictures... here you see the first dry fit of the engine...



in the following two pictures, you can see the problem, one side has a couple of bolts loosely installed, and the other side is off by a mile.... they're clearly far enough off that they just aren't going to work without significant modification, or raising the engine very high. I'm currently wanting to get the engine as close to the crossmember as possible, without the oil pan being below it.





it's pretty hard to get accurate measurements of the motor mount widths, so I came up with a fairly simple tool to do that. I cut two of these right angles with an eye at the top, I pass the motor mount bolt through them, one hanging left, the other right, line up the horizontal parts, and then you can easily measure them without errors.




After measuring the duramax mounting points, and the chassis mounting points, I confirmed that the mounts are about 2" too wide on the engine to fit the chassis side. I ordered a different set of SBC engine mounts that I'm going to try to see if I can make these adapters work. They're significantly shorter than the mounts that came with the 454. They should get here Thursday, but I probably won't have time to mess with them until next week.

[ericjon262]

The "new" SBC mounts were a very different style, and way shorter, which gained significant clearance, the unfortunate part about it, is that they also needed new frame side brackets.



the new mounts put the isolator on the engine, and the bracket on the frame, the Suburban is backwards from that with the isolator on the frame and bracket on the engine. I measured how far apart the through bolts were, and then took an isolator off and put the bolt patterns in CAD. After taking some measurements, I plasma cut a trail part and figured out the mounts wouldn't quite work the way I wanted due to some unforeseen interference. Rev 2 fit the chassis, and the isolators, and would have mounted the engine low in the chassis like I wanted to do, however, it actually ended up with the engine too low, and the exhaust manifolds hit the frame. so onto rev 2.1, which has a series of holes, 3/4" apart vertically, to allow for some coarse adjustment.



this allowed for the engine to FINALLY be bolted into the chassis. it's currently a little bit too high, and the mounts put the engine a little too far back, the downpipe is smashed into the firewall.





The new mounts look flimsy, and in reality, they are, these weren't meant to be a final install part, they're just mock up bits at this point. I currently have 2 options I'm considering.

1. Cut another set out with proper gusseting, the lower the engine 1/2-3/4", and 1-2" forward, wash hands, call it good.
2. Take a few more minutes, take the existing mounts out, off both the block, and the chassis, measure everything, put it all into CAD, and make a set of proper mounts, without special adapter plates, with isolators that can handle the 520+Ft-lbs a stock LB7 has to offer.

option 1 has the blessing of being a little bit faster, option 2 has the blessing of being a part I can sell and probably make decent money on. FWIW, Precision Fabrication wants almost $800 for a mount kit, just for bolting the engine into the truck, no trans crossmember, so something I develop could come in way south of that with similar functionality, and less parts, but there's alot of work to be done before I consider such an undertaking.

Edit:

Slow night at work, I got started on a custom mount setup... it's centered around these bushing inserts, they're cheap, strong, and readily available.

https://barnes4wd.com/products/dom-slee ... 4397456600

[The Dark Side of Will]

Do you feel that the energy suspension mounts that were successful in your fit check won't work?

[ericjon262]

Do you feel that the energy suspension mounts that were successful in your fit check won't work?

My overall concern is part life, these isolators were designed for a SBC, which is significantly lighter, and vibrates less than a typical diesel. it also doesn't typically make 500+ Ft-lbs as aggressively as a turbo diesel will

mounts are in CAD, these look pretty good. In total, I designed 4 individual parts, 2 frame side mounts, and 2 engine brackets. I realized that if I were to attempt to market these in any manner, adjustability would probably be somewhat helpful to the end user. the first frame mount I made had no adjustability (right side of 1st picture), and it wasn't as simple as slotting bolt holes, as the ribs that hold the bushing would get in the way. My plan was to make the frame side identical on both sides, to save time, but if I was going to make somewhat major edits to it, I figured I would just leave it and make another on the other side that was slotted to allow the frame side to slide fwd and back for adjustment. the slots are 7/8" long, and centered over the holes for the fixed mount, so the adjustable mount in the center position is the same as the fixed mount.



For some reason, the mounts on a duramax are offset from one another, this creates difficulties for developing mounts because most chassis, the engine mounts are directly accross from one another. unfortunately, this meant I had to make two seperate engine side brackets, the ears and gusset between them are identical side to side, but the plates that bolt to the block are different. the driver's side mount was moved forward, and the passenger side moved back on their pads, creating the necessary alignment.



The next step is a formal prototype, if that goes well, next will be a trans crossmember, and if that goes well, maybe make a few production parts?