[escapepilot]

Since I haven't been in the market for a new truck, I haven't paid attention to the new engines. I came across the L3B today and my first thought (after the shock of 310 hp, 430 torque specs) was Will It Swap! I would love to swap this in an S10. Just have to find out if it fits.

GM Engineer: L3B turbo-four is a true truck engine - Hagerty Media

We get some inside info on GM's latest truck powerplant from GM's assistant chief engineer for the 2.7-liter L3B turbo engine.

www.hagerty.com

 

[hotrodg726]

would go well in an early trifive truck too

 

[escapepilot]

I've been reading more about it and it sounds like a potential alternative engine for anyone interested. I still want a V8 in my '57, but this would be good in any number of other vehicles. Scoggin-Dickey lists the purchase price of a new one around $5000. I think I've spent that much on just the parts for my 383 not counting the intake/fuel delivery.

 

[BO185]

A stock 5.3L L84 355hp and 383 ft/lbs stock on 87 gas. MPG between them is same. Toss in some good gas 91+ and a tune and it will gain decent amount. The LB3 is a replacement for the 4.3L and 4.8L and which it has little more torque off line than the 4.8L for sure. But not on par with the 5.3L. Most cammed LS motors will be more for sure.

Main issue is unless you can fab your own mounts and DIY harness and install then will not be worth it even in an S10. When an LS/LT is bolt in plug and play now.

Main issue with LB3 is how much more will turbo support. But the turbo uses is good to 20ish psi I have heard. Granted not sure how much rest of motor will handle. lol

In the end would sound like a 4 cly. But would be different.

 

[hotrodg726]

A stock 5.3L L84 355hp and 383 ft/lbs stock on 87 gas. MPG between them is same. Toss in some good gas 91+ and a tune and it will gain decent amount. The LB3 is a replacement for the 4.3L and 4.8L and which it has little more torque off line than the 4.8L for sure. But not on par with the 5.3L. Most cammed LS motors will be more for sure.

Main issue is unless you can fab your own mounts and DIY harness and install then will not be worth it even in an S10. When an LS/LT is bolt in plug and play now.

Main issue with LB3 is how much more will turbo support. But the turbo uses is good to 20ish psi I have heard. Granted not sure how much rest of motor will handle. lol

In the end would sound like a 4 cly. But would be different.

I've done multiple 5.3 swaps that made 310 at the rear wheels with nothing more than 87 octane and a good set of headers. pretty easy and safe tune too.

 

[Shadetree55]

I've done multiple 5.3 swaps that made 310 at the rear wheels with nothing more than 87 octane and a good set of headers. pretty easy and safe tune too.

I had an 07 Silverado with a 4.8 and it was a powerless wonder. Got over to Paris TN one time with a pair of jet skis on a trailer and it lugged in the hills like crazy and loved gas---finally ditched it for a 2010 with a 5.3---night and day difference

 

[mr55/56]

You guys can not run fast enough to give me a turbo charged 4 cylinder anything for free.

 

[Shadetree55]

You guys can not run fast enough to give me a turbo charged 4 cylinder anything for free.

you seem to be an awfully fast runner for an old guy 🤣

 

[BO185]

I've done multiple 5.3 swaps that made 310 at the rear wheels with nothing more than 87 octane and a good set of headers. pretty easy and safe tune too.

If you had 93 out there be little more. lol I've had stock LS3 camaro's make 400 at wheels with exhaust and 93 gas tune. Now the LT are making tons of power N/A its actually easier to just delete the DI and go port on them for max effort swaps.

I had an 07 Silverado with a 4.8 and it was a powerless wonder. Got over to Paris TN one time with a pair of jet skis on a trailer and it lugged in the hills like crazy and loved gas---finally ditched it for a 2010 with a 5.3---night and day difference

The Gen IV 4.8L suck. GM didn't up the CR when they put flat tops and 799/243 heads. I have one in my shop truck. It made 250hp on dyno bone stock. Main issue with the 4.8 trucks GM used 3.23 in most of them and they are horrible off line towing. One reason I put 4.30's in mine. It actually tows really good now. 250k on it.

You guys can not run fast enough to give me a turbo charged 4 cylinder anything for free.

Main issue is the sound. Even in the trucks they come in sound is horrible. This is one reason Ram went back to V8 option over the turbo I6 for 2026 customers want a V8 in a truck.

 

[Shadetree55]

If you had 93 out there be little more. lol I've had stock LS3 camaro's make 400 at wheels with exhaust and 93 gas tune. Now the LT are making tons of power N/A its actually easier to just delete the DI and go port on them for max effort swaps.



The Gen IV 4.8L suck. GM didn't up the CR when they put flat tops and 799/243 heads. I have one in my shop truck. It made 250hp on dyno bone stock. Main issue with the 4.8 trucks GM used 3.23 in most of them and they are horrible off line towing. One reason I put 4.30's in mine. It actually tows really good now. 250k on it.

Main issue is the sound. Even in the trucks they come in sound is horrible. This is one reason Ram went back to V8 option over the turbo I6 for 2026 customers want a V8 in a truck.

as the old saying goes---no substitute for cubic inches---BUT boost from a turbo sho' helps LOL. My wife's little 2.0 turbo is scary fast. It will hit 142 in a heart beat and wants more but I didn't without a bit more down force LOL.

 

[BO185]

as the old saying goes---no substitute for cubic inches---BUT boost from a turbo sho' helps LOL. My wife's little 2.0 turbo is scary fast. It will hit 142 in a heart beat and wants more but I didn't without a bit more down force LOL.

I want to put a blower on the shop truck in a bad way but not sure the 4L60e with 250k on it will like it. LOL

 

[Shadetree55]

I want to put a blower on the shop truck in a bad way but not sure the 4L60e with 250k on it will like it. LOL

might get ONE good run out of it LOL

 

[Postman57]

I have that motor in a newer Colorado. Works reasonably well. Throttle response is good, though it seems to run out of steam further up the rpm range. It’s not very efficient unless you drive it VERY conservatively. And the comments about the sound are something I’d agree with.
It’s an intriguing swap candidate, especially into a car with less room under the hood (though the turbo plumbing might complicate your life!). But I’m guessing you’d really want a science project to choose it over a 5.3.

 

[Shadetree55]

I have that motor in a newer Colorado. Works reasonably well. Throttle response is good, though it seems to run out of steam further up the rpm range. It’s not very efficient unless you drive it VERY conservatively. And the comments about the sound are something I’d agree with.
It’s an intriguing swap candidate, especially into a car with less room under the hood (though the turbo plumbing might complicate your life!). But I’m guessing you’d really want a science project to choose it over a 5.3.

Might be a good candidate for a Vega LOL.

 

[hotrodg726]

Might be a good candidate for a Vega LOL.

I really want to do a turbo LS in a Vega

 

[Shadetree55]

I really want to do a turbo LS in a Vega

it would be fun...I drove a friend's Vega yrs ago with a 383 and it was ALMOST scary LOL.

 

[BO185]

I have that motor in a newer Colorado. Works reasonably well. Throttle response is good, though it seems to run out of steam further up the rpm range. It’s not very efficient unless you drive it VERY conservatively. And the comments about the sound are something I’d agree with.
It’s an intriguing swap candidate, especially into a car with less room under the hood (though the turbo plumbing might complicate your life!). But I’m guessing you’d really want a science project to choose it over a 5.3.

What year one do you have? Is it the turboplus or HO. All 2025 new ones are HO. The plus can be turned to an HO.

 

[Postman57]

I have the HO (310 hp) 2024 ZR2; off idle torque is impressive. As I said, it’s not super economical. That said, I just took it to Big Bend and it was flawless off road.