I could see me doing this toward the end of the year. How well do you think this would work for towing? Our stock, higher mileage 1FZ sucked pulling a 18ft camper back in September and if the extra power of this engine wouldnt be the same then Im all over swapping it.
New Build: GM 4.2L Atlas into '91 FJ80 (1 Viewer)
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- #122
Atlas components
Yes, there's been quite a bit of interest in some form of kit. To this point everything completed has been either doing the complete swap or providing a drop-in package of engine-transmission-adapter-mounts-wiring.
So, it will boil down to what's essential for helping people get a working swap done-- the complication is the strange combination of pieces (ie the 'correct' versions of 4L60E, output shafts, flexplates, PCMs, harnesses) plus getting the PCM adapted correctly... it's definitely more than mounts and a cross-member. So, if people are sourcing from the local salvage yard the components need to be specified pretty clearly.
On the I-6, there were some running changes of PCM, wiring, VVT hardware and the like, too, to make it more complicated. There will definitely be a hardware set available this year, so we'll post up when it's together.
Yes, there's been quite a bit of interest in some form of kit. To this point everything completed has been either doing the complete swap or providing a drop-in package of engine-transmission-adapter-mounts-wiring.
So, it will boil down to what's essential for helping people get a working swap done-- the complication is the strange combination of pieces (ie the 'correct' versions of 4L60E, output shafts, flexplates, PCMs, harnesses) plus getting the PCM adapted correctly... it's definitely more than mounts and a cross-member. So, if people are sourcing from the local salvage yard the components need to be specified pretty clearly.
On the I-6, there were some running changes of PCM, wiring, VVT hardware and the like, too, to make it more complicated. There will definitely be a hardware set available this year, so we'll post up when it's together.
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- #123
In fairness, I'd have to say that it will depend on the weight/nature of the load-- That Atlas has a broad, flat torque curve, with at least 250 ft-lbs of torque from idle all the way up... however, I'd be the first to point out that it's not exactly an LQ9 Escalade motor with 400+ ft-lbs across the board. So, if you're towing 8000 or 10,000 pounds, the Atlas is going to leave you underwhelmed.
The main reason the I-6 gets to 290HP, over the 212 of the 1ZF, is largely the breadth of the torque curve-- Redline is 6300 RPM and it makes torque all the way up-- getting it's 290HP somewhere around 6000 RPM. The 1ZF is a lower-revving engine, so redline's 5000 and peak torque's down quite a bit from there. The Atlas also has no problem dropping down a gear in the 4L60 and revving up-- I notice that I can take steeper hills faster with it-- no surprise. But, if I were towing heavier loads, I'd probably look at one of the V8 swaps-- Those LS2 conversions being done here on MUD will be nice and will handily out-tow any of the Atlas.
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- #124
This swap has the gears turning in my head big time. Come out with a mount kit, oil pan, and a required parts list and I am in. I can do my own wiring, the wiring on this type of swap should be super simple compared to other things I have worked with. Are there any other options out there for tcase adapters or is the $1200 Mark's unit the only one? I wish I still had my fully built 4l60E out of my Camaro
We're doing our own adapter to both the 4L60 (the one that doesn't have the shaft interference issue) and the 5-speed manual.
Which Camaro? The input shaft changed, as did flexplate, from LT/SBC series F-Bodies to the LSx series.
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- #125
Definitely, if you can offer a kit for the 1FZ, including a fresh modern motor, I would imagine that you would have people lining up to get the work done, myself included.
I need to make a trip down to Moab, then over to Denver to see friends-- would be nice to give people a chance to drive one of these trucks with the Atlas in it to compare to 3FE or 1ZF equipped trucks.
I ran an LT1 Camaro but it is long gone and I do miss it. Which version 4l60E is the one to use with your setup? If you head down to Denver please let me know, I am an hour away. A few years back in the RX-7 world a company called Granny's Speed Shop was making bolt in kits for the LSx series engines into the FD chassis. The whole idea was a great plan but the final kit was around $8k not including engine and trans or the chassis. I almost purchased an FD rolling chassis simply to swap it but the final cost was too high in the end and I couldn't justify it even after having the engine and trans. I know now that costs are more reasonable for an Rx-7 swap but they were not at the time. What I am getting at is that if you can offer a "kit" that includes the t-case adapter, weld in mounts, and the recipe book for what parts to source and not charge $8k you will be in business. It's easy to put a high price on things, but you also have to look at the initial cost of the truck, which in many cases is well under $10K (hopefully more like $5k) and putting another $10k in it is not feasible or acceptable. With emissions coming down hard, fuel cost going back up, and high mileage Land Cruisers everywhere it's a great plan if costs can be kept reasonable. From my perspective if you could offer a kit in the $2500 or less price range you would be successful. This is assuming that these GM 4.2's and 4l60E's can be had for less than $1k out the door. The total needs to be kept close to the cost of a TRD supercharger to sway people. There are other swaps out there too. I really like the Toyota V8 swap that Slee has done but I think the final cost is going to be so high that only the wealthy folks can afford it. Frankly if all of us 80 owners were wealthy we wouldn't have 80's. Also the cost of Lsx engines is far too high be sourcing one of those for a project like this in my opinion. What we need is a reasonably priced swap option for the blue collar 80 owners. Soon enough the 1FZ and the 3FE will not be able to pass emissions and that is going to be a huge driving force to swap.
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I think it is a bit different - I would like to keep 80 because: it is more rigid and universal truck. 100 series are pretty much 80 series based. But 200s - sorry I am not buying gay's toy. I like old style and design - just like lot of guys here keep classic 50 and 60 full size cars - they are unique. They were built using engineer's understanding of beauty. Look at the new generation of SUV's and cars - they all look like soap bars with little wheels... After swap I looking into keep main for next couple of decades - just for fun...
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- #128
Sweet F-Body! Unfortunately, most of the post 1993 4L60E's with the 6-bolt output flange have a 'wide pan' on the transmission-- so we are pulling mid-00's 4L60s from the Atlas truck series that have a narrower 'notched' pan. that one works great with the FJ and FZJ, due to better shaft clearance for the front driveshaft.
We're starting to talk about going to Moab in the spring-- maybe with a trip in to Colorado-- so will keep you posted.
Agree with all the comments on 'swap costs'-- The LQ series (Silverado/Yukon etc) engines are super affordable in the salvage yards. (I bought one recently for $465, low miles-- 300HP of perfection) BUT, the cost of the motor becomes irrelevant if the kit cost or swap cost ends up being a lot higher than the cost of the engine. Or, more to the point, a lot more than the cost of a rebuild or an intact replacement motor.
Well seeing as how the 80 is only rated for 5k lbs I dont see me trying to do 8k plus no matter the engine in it. It seems stock the 1FZ was doable but marginal as you get close to 5k lbs and if the extra HP of the 4.2 would make it not as marginal Im inclined to go that route instead of the extra hassle of a V8 swap.
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- #130
IIRC, the mid-run Trailblazer towing capacity ranged between 5400 and 5800 pounds with the 4.2L, depending upon equipment, so it's similar.
Looks like the curb weights between the trucks are similar. The Trailblazer owners Ive talked to that tow with the I6 up to max never complained about performance.
I may do this later this year as it looks like it will work fine for my needs.
Plus your 80 will get over 400 lbs lighter with the engine/transmission swap, which is not chump change.
That offsets the weight of the roof rack, sliders, spares and maybe even a kid or two
Nay said:Plus your 80 will get over 400 lbs lighter with the engine/transmission swap, which is not chump change.
That offsets the weight of the roof rack, sliders, spares and maybe even a kid or two
Oh yeah I'd still be ahead or at least back to preswap weight with more power. No roof rack weight since I'll never use it and don't like them. Front bumper will be light as will the rear and whatever sliders weigh.
I like how much more straight forward this is compared to the v8s.
Now to start saving and working overtime to pay for it.
Moby
GOLD Star
So you're not using the Mark's 4L60E to LC tcase adapter this time around? Seemed like you were happy with it for the previous 5 cylinder swap. Or am missing something and this is some other adapter?
In other markets, the 80 was rated to tow at higher capacities than in the US. IIRC, it was something like 7500 lbs or roughly 50% more than US rigs.
Of course, that capacity. Americans still want to get there ASAP, so yeah, so when looking for a fast heavy-hauler, the Atlas thing won't work. Doesn't mean it won't be able to tow that much, just not in a hurry.
Personally, I'm unlikely to ever tow the US-rated max load, so makes no difference to me. Fully loaded, our M101 CDN should still seem like easy pickings and, while not as fast as a V-8 might be, I'll bet the Atlas will have all the pep I need.
There's also another advantage I see to an Atlas swap. Lots of swaps are made with the aim for more power. And the 80 can handle that within reason, for the most part, from what I've read, but there generally is going to be more stress, wear and tear on the drivetrain if you do decide to go with a swap. The Atlas has more oomph than the 1FZ, but will probably suit the drivetrain's design limits better than a more powerful swap would. Thus, you'll likely tend to get more overall reliability with the Atlas -- and that's something all 80 owners value.
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- #136
Towing
We think the broad powerband helps-- you are making the same torque at 5500 RPM that you are at 1500, so that the agility of the PCM to drop a gear or two, helps you in uphill towing situations.
I'm not a big advocate for towing heavy loads with the FJ or FZJ anyway, though. Wheelbase is pretty short and (at least in the early FJ80s) they don't exactly have 'too much' for brakes. I always roll my eyes a little when I see an 1991 FJ80 hooked to a trailer carrying a full-size (what is obviously a 3500-4500# or more) vehicle on a steel trailer. The brakes on those early 3FE rigs were under-spec'd anyway; throw a big load on a trailer (even with electric trailer brakes and braking controller...) and I think you're asking for trouble. JMHO. :whoops:
We think the broad powerband helps-- you are making the same torque at 5500 RPM that you are at 1500, so that the agility of the PCM to drop a gear or two, helps you in uphill towing situations.
I'm not a big advocate for towing heavy loads with the FJ or FZJ anyway, though. Wheelbase is pretty short and (at least in the early FJ80s) they don't exactly have 'too much' for brakes. I always roll my eyes a little when I see an 1991 FJ80 hooked to a trailer carrying a full-size (what is obviously a 3500-4500# or more) vehicle on a steel trailer. The brakes on those early 3FE rigs were under-spec'd anyway; throw a big load on a trailer (even with electric trailer brakes and braking controller...) and I think you're asking for trouble. JMHO. :whoops:
Here is a picture of the rear sump 4200 oil pan casting before any machining operations occur...
[URL=http://img98.imageshack.us/i/p2080990.jpg/]
[URL=http://img98.imageshack.us/i/p2080990.jpg/]
Holy moly, that there is a piece of metal!
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- #139
On the 4200 the oil pan is a structural part of the block.... also the factory ones are cast using lost foam which is very expensive to tool up for but you can cast a thinner part. We have to use sand casting so its bit thicker than the oem pan to get the metal to flow.
Side benefit - you not going to put a rock through it.....
Side benefit - you not going to put a rock through it.....
