- Thread starter
- #61
Yeah, the weight savings over the "F" Series motors are insane.
I'd love to put one in a welterweight FJ40 someday.
New Build: GM 4.2L Atlas into '91 FJ80
- Thread starter TwoTonic
- Start date
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Yeah, the weight savings over the "F" Series motors are insane.
I'd love to put one in a welterweight FJ40 someday.
- Thread starter
- #62
Atlas Bell-housing
The engine-bell bolt pattern is actually "new Corporate GM" patttern-- It's the same as the Colorado/Canyon/H3 I-4/5 pattern, rather than the SBC/LSx pattern. However, on the I-6 they do use a heavier duty Torque Converter and flexplate, so it's a hybrid of I-5 and V8 pieces.
for those interested in going manual, there IS a cool set of pieces that can be used, since the input side pattern on the Aisin is similar to some Toyota R15x series gearboxes. It's the same pattern, in fact, which is allowing some open-minded HEEP owners to swap to better gearboxes from Aisin/'yota.
The engine-bell bolt pattern is actually "new Corporate GM" patttern-- It's the same as the Colorado/Canyon/H3 I-4/5 pattern, rather than the SBC/LSx pattern. However, on the I-6 they do use a heavier duty Torque Converter and flexplate, so it's a hybrid of I-5 and V8 pieces.
for those interested in going manual, there IS a cool set of pieces that can be used, since the input side pattern on the Aisin is similar to some Toyota R15x series gearboxes. It's the same pattern, in fact, which is allowing some open-minded HEEP owners to swap to better gearboxes from Aisin/'yota.
Got it - I never pay attention to engine swaps, and I have too much to learn here. I have the feeling I am going to do this and it is going to be humbling
I really appreciate the time you are taking to respond to questions. Along with some time on TrailVoy, the big picture is settling in and that's what it takes to pull the trigger and learn the small bits along the way.
Part of my goal in doing a swap is to become a lot more familiar with the overall engine platform and its "connections" - if you are going to keep a rig for 20 more years, it is a good idea to know how it all works. You never get there with the stock fanboy stuff (especially when it goes forever), and that's actually a detriment in my mind given how expensive 80 series OEM stuff is and how much more expensive it will be in another 5 years.
Appreciate the parts documentation, I'll pay a premium to "cheat" on a complete setup if that makes sense for sure especially if it comes with really low miles.
- Thread starter
- #64
The "Wheel Stuff" test
By the way, we did pull the springs the other day to check 'complete wheel/axle articulation' clearance with the motor-transmission-adapter-transfer case in place. We found that with the I-6, "special" 4L60, adapter and case we had no clearance issues anywhere along the driveline.
This is with a "swap" (end for end) of the engine oil pan, which is typical for any of the applications using the 4.2L Atlas.
The 'front sump' hole-through-the-pan just doesn't work in anything other than the TrailVoy series, so most everyone using the 4.2 is moving to a rear sump. (Several people have swapped them into cars, as well, and have gone rear sump)
The good news is that we shouldn't have to mod or clearance anything else.
I'm coming to the conclusion that the Atlas really does fit better in the FJ80s.
Pics to come.
TT
By the way, we did pull the springs the other day to check 'complete wheel/axle articulation' clearance with the motor-transmission-adapter-transfer case in place. We found that with the I-6, "special" 4L60, adapter and case we had no clearance issues anywhere along the driveline.
This is with a "swap" (end for end) of the engine oil pan, which is typical for any of the applications using the 4.2L Atlas.
The 'front sump' hole-through-the-pan just doesn't work in anything other than the TrailVoy series, so most everyone using the 4.2 is moving to a rear sump. (Several people have swapped them into cars, as well, and have gone rear sump)
The good news is that we shouldn't have to mod or clearance anything else.
I'm coming to the conclusion that the Atlas really does fit better in the FJ80s.
Pics to come.
TT
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Subscribed...it's gotta be this or diesel...
I'm looking forward to the 6l80s coming down in price. This engine and that tranny would be the shiznetz! If there was a turn key pan and harness, I think this swap would be seen more. That is what pushed me over to the 5.3 on my swap. Opportunity for you TT. 
updates?
Subscribed.....can't wait to see the outcome (performance-wise)
I'm interested, also.
But after sticking a 350 Chevy in an FJ55 years ago (mostly by buying the help of others), I have a natural reluctance to start hacking away. But the pluses in this project are very alluring. I just gotta watch
But after sticking a 350 Chevy in an FJ55 years ago (mostly by buying the help of others), I have a natural reluctance to start hacking away. But the pluses in this project are very alluring. I just gotta watch
- Thread starter
- #72
Back online after the holidays
Sorry to be quiet on this one-- holidays have been crazy with work, family and travel. We do have pretty much all the parts laying around here now, so are hoping to get a "push" on and finish it up. We'll get some updates and photos up over the next couple of weeks.
Still think the I-5/6 are a natural upgrade for the 3FEs in the FJ80s. Power and torque are big increases, weight's down and fuel efficiency is really a lot better.
The fit is good for the I-6 (except for the pan swap-- really no way around that) and no nip-tuck-hack-nibble required.
I did just have the I-5's fuel light come on this afternoon-- At 304 miles... with the 3FE it would have come on at 195. It's like getting an extra 100 miles out of every tank of crappy 85 Octane gasoline.
TT
Sorry to be quiet on this one-- holidays have been crazy with work, family and travel. We do have pretty much all the parts laying around here now, so are hoping to get a "push" on and finish it up. We'll get some updates and photos up over the next couple of weeks.
Still think the I-5/6 are a natural upgrade for the 3FEs in the FJ80s. Power and torque are big increases, weight's down and fuel efficiency is really a lot better.
The fit is good for the I-6 (except for the pan swap-- really no way around that) and no nip-tuck-hack-nibble required.
I did just have the I-5's fuel light come on this afternoon-- At 304 miles... with the 3FE it would have come on at 195. It's like getting an extra 100 miles out of every tank of crappy 85 Octane gasoline.
TT
Great upgrade. Subscribed to see more in this thread.
I live outside of US, really looking to do the same on my rig. My rig is 80FZJ, 1FZ-F with H151F manual trans. the MPG is terrible lately with all upgrades I did - front, rear ARB with 2" OME lift and 33" tires and about of 300 KG of wight constantly in the trunk. I have ordered new carb - but in general I have no real hope on decreasing of MPG with outdated carb aspiration.
I have question to enthusiasts here - is there any possibility to purchase the fully ready to install engine LL8 with all bells and whistles as PCUs and etc with already mounted H151F trans onto? If not could you please direct me to the shop/person who could do that for reasonable price.
My fist option was to put the diesel 1HD-T - but I am not big fan of diesel as the winters here are very cold. And jellying up of diesel fuel here is very common.
I live outside of US, really looking to do the same on my rig. My rig is 80FZJ, 1FZ-F with H151F manual trans. the MPG is terrible lately with all upgrades I did - front, rear ARB with 2" OME lift and 33" tires and about of 300 KG of wight constantly in the trunk. I have ordered new carb - but in general I have no real hope on decreasing of MPG with outdated carb aspiration.
I have question to enthusiasts here - is there any possibility to purchase the fully ready to install engine LL8 with all bells and whistles as PCUs and etc with already mounted H151F trans onto? If not could you please direct me to the shop/person who could do that for reasonable price.
My fist option was to put the diesel 1HD-T - but I am not big fan of diesel as the winters here are very cold. And jellying up of diesel fuel here is very common.
- Thread starter
- #75
Pre-Packaged LL8 with bells/whistles
The shop is thinking about offering one. The fit on the 3.7L and 4.2L is good enough that it's almost a drop-in... They'd like to offer a fresh LL8 and 4L60E, with harness and adapter-- ready for the FJ owner just to bolt on their transfer case and hook up a few wires and the throttle and fuel. Where are you located?
Shop's in Pacific NW in US.
The shop is thinking about offering one. The fit on the 3.7L and 4.2L is good enough that it's almost a drop-in... They'd like to offer a fresh LL8 and 4L60E, with harness and adapter-- ready for the FJ owner just to bolt on their transfer case and hook up a few wires and the throttle and fuel. Where are you located?
Shop's in Pacific NW in US.
This would be beautiful - the typical issue most of us have is either problems with access to fabrication or zero ability to deal with wiring. It's enough to keep you from pulling the trigger unless you have a wallet that doesn't dent easily.
I hope it's not just for the FJ80 though, to replace the 3FE, as the 1ZFE is an equally good candidate on the later model 80's.
Keep us posted!
Moby
GOLD Star
Where in the NW?
Oh boy! Keep us posted...
Man, anytime someone can get a kit to help with a conversion, it's like gold. Are y'all going to sell oil pans for that engine and also look into 6l80s?
