Chevy Gen V 4.3 LV3

[XCRN]

So I have been mulling over the idea of throwing in a LV3 4.3 or a L83 5.3 into my TJ. I want this TJ build to be tailored towards daily driving and longer camping trips like back country discovery routes, exploring desolate areas, things where gas stops are infrequent, so range is a concern. The LV3 4.3 looks to get great fuel mileage in trucks that weigh 2000lbs more and has plenty of power 285hp 305ft/lbs. And they seem to be smooth running engines that do not sacrifice "comfort" for power. Its hard to tell about the L83 specifically from people since the fuel mileage is across the board and sounds like they only got it because its faster than the 4.3.

I would be replacing the Gen 3 LM7 5.3 in my Jeep and moving that to a more dedicated trail rig since it's a loud and rowdy motor that does take away from some of the fun during longer trips (but is fun on single day playing around) and only gets about 250-270 miles to the tank on the street which is better than the 4.0 it use to have but I will need more for some of the trips I have planned in Canada. I think going Gen 5 motor would be more ideal than the cammed Gen 3 for what I want out of this particular TJ but its a tossup between getting one of these 4.3 LV3 V6 motors or rebuilding the L83 gen V 5.3 I have lying around doing nothing. I already figured out what I need to do to run the direct injection system and I am not worried about how to do this. I am curious if anyone has done an LV3 swap and if they think they are missing out on the V8, or if the LV3 and L83 would accomplish the same thing and have about the same range.

 

[MountaineerTom]

I don’t have any answers, but it sounds interesting.

 

[Fughuert]

I looked into the lv3 v6 for a different vehicle. Big pro for me was it’s a very light engine. It’s been used in a few buggies I’ve seen. There’s a company that makes a nice standalone harness for it.

But I honestly don’t think you’ll see much better fuel economy look at what the trucks with the v8 get vs v6, only gain is minor.

Turn off for me was lack of aftermarket for it, if you’re ok with the stock power and won’t ever want more that’s fine. But that’s about the power the jk makes, so if you think that’s adequate with larger tires you’ll be fine.

And I couldn’t find any good info for using it with a manual, if you’re planning on the stock trans it comes with that’s a non issue.

 

[Jezza]

In my experience the 4.3s are usually harder to find and more expensive whenever you do as compared to a similar 5.3.

 

[erokj]

I was researching installing a LV3 into my CJ6, but after all the hoops you have to jump through, a 5.3 is just easier.

 

[XCRN]

I was researching installing a LV3 into my CJ6, but after all the hoops you have to jump through, a 5.3 is just easier.

So what hoops are you talking about? Did you do a Gen V 5.3 or a Gen 3 or 4?

 

[XCRN]

I looked into the lv3 v6 for a different vehicle. Big pro for me was it’s a very light engine. It’s been used in a few buggies I’ve seen. There’s a company that makes a nice standalone harness for it.

But I honestly don’t think you’ll see much better fuel economy look at what the trucks with the v8 get vs v6, only gain is minor.

Turn off for me was lack of aftermarket for it, if you’re ok with the stock power and won’t ever want more that’s fine. But that’s about the power the jk makes, so if you think that’s adequate with larger tires you’ll be fine.

And I couldn’t find any good info for using it with a manual, if you’re planning on the stock trans it comes with that’s a non issue.

I think stock power is fine which looking at the torque curve of a LV3 os probably better than my 5.3 now in the low speed. And ill be going with a 6L80 on either engine since I have 2 of those lying around. I considered and 8L90, but I am leary on the reliability on them and do not know many people that service the 8speeds like I do the 6-speeds.

 

[Raceanything]

I purchased a '71 CJ -5 last year with an LV3 mated to a nice SM465 and Dana 18.The project was not finished or running and the builder died so I have no info other than I saw some of his other builds and he seemed to know what he was doing. I don't want the Jeep but I want to keep the motor and swap it into my little lowered aluminum flat fender. Probably put a short auto or a car 4spd behind it but I don't know my options for keeping it 4wd.

 

[Don 06TJ]

Who makes the stand-alone wiring harness for the GM LV3 engine

 

[05ImpactLJR]

Are there any updates on information to this swap? Have there been any swaps successfully done to a TJ/LJ as of yet? This is the swap I'm after. I have been looking into what Scoggin Dickey has done with them and a few others now offer more support, but no Jeep specific swap info has come up.

 

[Artsifrtsi]

I haven't seen any stand-alone kits for it, but if there were, I'd think the L3B 2.7l 4 cyl would be a great engine in the TJ. It's in the Silverado, canyon/colorado and Cadillac CT4-v... In Cadillac trim it is rated 325 hp @ 5500 and 380 lb-ft @ 2000-4000, and somewhere between 80-160 lbs lighter than the LV3

 

[tnjeepguy]

Cadillac trim it is rated 325 hp @ 5500

My TJ has never seen 5500 rpms.

 

[Artsifrtsi]

My Tj has never seen 5500 rpms.

Those numbers were for the Caddi sport sedan... (and do you care about the HP or torque in a Jeep?)

"The motor was developed specifically for truck applications, and the motor delivers peak torque from 1,500 to 4,000 rpm. Additionally, it makes 22 percent more torque than the 4.3L V-6 LV3 it replaces." (https://gmauthority.com/blog/gm/gm-engines/l3b/)

Also, they are now higher output over the first couple years... up from 348 lb/ft to 420lb/ft. (They are actually seeing 430 lb/ft in real world numbers)

And it's built in your home state...

 

[XCRN]

Are there any updates on information to this swap? Have there been any swaps successfully done to a TJ/LJ as of yet? This is the swap I'm after. I have been looking into what Scoggin Dickey has done with them and a few others now offer more support, but no Jeep specific swap info has come up.

I bought the motor and harness. Just have not done anything with it yet. Looking at it, its pretty much the same as swapping a Gen V but there are no mounts specific to this. The block side is the same as the Gen 5 V8 counterparts, but the block mounting holes to bell house face is different between the V6 and V8. So if you were to use the V8 frame mounts from Holley or Novak that offer Gen V V8 engine mounts and position them per their instructions, the transmission would move forward like 4-5inches which on a short TJ is not exactly a bad thing.

 

[freedom_in_4low]

the block mounting holes to bell house face is different between the V6 and V8. So if you were to use the V8 frame mounts from Holley or Novak that offer Gen V V8 engine mounts and position them per their instructions, the transmission would move forward like 4-5inches

are the mounting holes centered along the length of the engine, or are they consistent to the front of the engine?

Said another way....if you put either engine on V8 mounts would the crank pulley end up in the same place and it's just the rear that moves?

which on a short TJ is not exactly a bad thing.

Both from a driveline standpoint and it also might not be terrible to move some weight forward.

 

[XCRN]

are the mounting holes centered along the length of the engine, or are they consistent to the front of the engine?

Said another way....if you put either engine on V8 mounts would the crank pulley end up in the same place and it's just the rear that moves?



Both from a driveline standpoint and it also might not be terrible to move some weight forward.

The crank pulley will remain in same spot if you were to put this V6 on existing V8 mounts.

 

[freedom_in_4low]

The crank pulley will remain in same spot if you were to put this V6 on existing V8 mounts.

That seems so odd as a design engineer; the whole supply chain would benefit from locating them off the rear of the engine instead of the front (they could share frames, etc)

but I'm guessing it's rooted in the assembly process....making it so the factory can't accidentally install a V6 drivetrain into a V8 chassis and vice versa.

 

[XCRN]

That seems so odd as a design engineer; the whole supply chain would benefit from locating them off the rear of the engine instead of the front (they could share frames, etc)

but I'm guessing it's rooted in the assembly process....making it so the factory can't accidentally install a V6 drivetrain into a V8 chassis and vice versa.

I completely agree with you, I always thought it was odd. I never paid attention to the trucks these came in but I wondered if they leave the front of the engine in the same place and have the trans move positions or the opposite.

 

[freedom_in_4low]

I completely agree with you, I always thought it was odd. I never paid attention to the trucks these came in but I wondered if they leave the front of the engine in the same place and have the trans move positions or the opposite.

20 years ago, it appeared that the back of the engine and transmission were in the same place, and the front moved, as evidenced by a giant fan shroud to take up the gap between the radiator and the mechanical fan. I would assume they are doing it the same way today.

 

[Wildman]

My TJ has never seen 5500 rpms.

Then you're not driving spiritedly enough. My 4 banger used to see 5,500 RPM's every time I drove over Snoqualmie pass. 3rd gear & 60 MPH was good for around 5,500 RPM's.

Those numbers were for the Caddi sport sedan... (and do you care about the HP or torque in a Jeep?)

"The motor was developed specifically for truck applications, and the motor delivers peak torque from 1,500 to 4,000 rpm. Additionally, it makes 22 percent more torque than the 4.3L V-6 LV3 it replaces." (https://gmauthority.com/blog/gm/gm-engines/l3b/)

Also, they are now higher output over the first couple years... up from 348 lb/ft to 420lb/ft. (They are actually seeing 430 lb/ft in real world numbers)

And it's built in your home state...

Not a bad sounding engine for a swap.