There is zero reason the goals can't be met I'd the turbo, hot side, cooling, and tune are all correct.

 

The OP drives a truck. Doesn't ride an engine hovering 3 feet off the sands of Tatooine. The truck has limits.

First gen Ecoboost...

Forged I-beam rods, forged crank, forged pistons with upper ring supports like a diesel engine for long-term operation at high boost, piston cooling oil squirters, water cooled turbos, direct injection with variable rail pressure, twin independent variable timing cams, 3 IAT sensors, 2 MAP sensors, cylinder head temp sensors, dual wide-band O2 sensors, advanced knock sensors

First gen Ecoboost had peak torque around 2500 rpm, and peak Hp around 5500 rpm.

Tuned is TOTALLY DIFFERENT than stock. I have a table top torque curve from 2000 - 4100 rpm on chassis dyno. Horsepower peaks around 4500 rpm. The reason my Hp peaks so low is because there were huge gains of torque in the low- and mid-range but the engine's got no top end. I'm still making more power than stock above 5000 rpm, but the curve is extra stout in the lower rpm's. I think a stock Ecoboost runs 15 psi, mine is 18 psi and it spools turbos faster off-idle.

I'm just sharing information to help people realize these engines are radically different. The Ecoboost has some pretty nice parts in order to live. It's not a high horsepower hot rod engine, but it is made to work.

 

600ftlbs out of a 5.3 isn't that easy if you want to keep 100,000 plus mile durability, Hell just getting 600ftlbs out of a budget 5.3 while on pump gas is not going to be easy let alone do it under 3,000rpms.

I would like to see a TT 5.3 smoke any modern diesel engine, Hell the Duramax makes over 900ftlbs at 1,600 rpms stock and with a slight tweak they are well over 1,000ftlbs and will do it all day everyday, I love my LS engine but there is no way in hell a 5.3 can compete with that.

 

I mean to be fair here, I've seen so many Duramaxs need $12,000 in fuel system components before ever hitting 100k miles that the number sounds like an exaggeration. And, in a diesel it isn't the diesel alone that makes it perform so much different, the Allison transmission honestly deserves more than 50% of the credit for what the trucks can do.

I can build a fully forged LS engine for less than the cost of a catastrophic fuel system failure repair for a 6.6 duramax. Unless you need all the max towing capability of the duramax with the engine braking and stuff to manage a really heavy load, it's not really worth it and never more economical to get a diesel...ever, ever, ever, ever...I did the math on the fuel saving vs the cost of the diesel upgrade once and you have to drive a truck for about 4million miles before you break even on the upgrade cost from the fuel mileage difference. The things cost so much to own.

The goals the OP wants are completely reasonable honestly.

 

This is something I’d love to see tried out. I’m also of the opinion that it’s completely reasonable. I don’t know how long it would go for and you’d definitely want a very good charge cooling setup.
Now the big question is who’s gonna be the Guinea pig 😋

 

If i had these struggles, I'd do a PD blower, no way I'd do a custom turbo setup, I think a turbo setup would be over kill.

 

Torque at the tire is what moves the vehicle. If you really want to know what's going on then plot Torque At Tire vs. MPH given your engine torque curve, trans ratios, and axle ratio. Do it from 2000 - 5000 rpm for each gear so you get a good illustration in ranges that you might see towing. Then compare that to the Ecoboost truck and you'll get a better idea what's going on. It will also help you set a target for how much torque your engine will need to match.

I think you're going to find that final drive ratios play a big role and that the Ecoboost gets a big lift from it's 6-speed transmission. But you can adjust your axle gear ratio to try to compensate for that. And more gear makes things easier on engine and trans, too.

I remember when the Ecoboost first came out some idiot abused his truck in a towing drag race with a 6.4L diesel Superduty. Something like 15K pounds up a hill. The Ecoboost actually won.... it's all about the gears, baby! He hurt the truck with his antics and major parts began breaking within a year or two. Like I said, guy was an idiot that didn't understand how things wear out and get broke. Learn from him and don't play beyond the reasonable limits of your truck.

 

You obviously have no diesel knowledge, I can rebuild the fuel system on a Duramax a few times for 12k lol And what number sounds like an exaggeration? The torque numbers? Hell modified they are putting down double that.
PS: The factory rating is at the flywheel so the trans has nothing to do with it, The fact is diesels are designed to make big torque and do it all day, I'm not saying a turbo 5.3 won't make good power but it's laughable to try to compare it to a diesel engine whether it's a Duramax/Cummins/Powerstroke or others and to say it will put perform them is just stupid.
Like I said earlier, You can build a 5.3 to make the number the OP is wanting but to do it on a 10k budget plus run on pump gas and last 100,000 plus miles reliably is not going to be easy at all.

 

You don't want to lay down a bunch of torque in 4th gear, it'll damage the transmission. So I think you just focus on 3rd gear pulls up hills, which is about 3,000 RPM after upshift. It would make a world of difference if you could pull hills 450 lb ft at 3,000 RPM.

And then you cruise in 4th around 2000 RPM which will help prevent transmission gear hunting.

 

I've seen dozens of trucks with under 100k that needed all new injectors, pump, high pressure, lines, etc... that's the number that sounds exaggerated, the number of them that need a completely new fuel system every 60k miles because they get metal shavings in a fuel system that can't handle what they try to make it do. I never indicated anything else was exaggerated.

Every time the topic of making a gas engine tow better comes up the diesel people always go straight to "just get a diesel and sell the gasser" and it's never helpful to the topic.

I try not to comment on diesels though because the people who bring it up are too emotional to have a conversation about it without feeling like a part of their personality is being attacked or something every time.

If you don't think that what the OP wants is feasible then you maybe you have the same experience with LS turbos that you think I do with diesels... Because I have already built what the OP is talking about and that build has put about 80k miles on since the turbo kit was installed on a truck that already had 140k on the clock at the time of install. It. Works. Just. Fine.

I won't say anything more about diesels though because it's not helping the OP with turbocharging a LS which is really the only reason to comment in their thread.

Super easy to do OP, even on 90 octane like I did it.

 

You wouldn't need even that much to get to the OP's stated goals. 333 ft-lb at 3000 RPM is the same as 500 ft-lb at 2000 RPM.

 

I know the point you're trying to make but it doesn't work out that way in the practical world because engines are variable speed and almost all petrol engines operate across a similar rpm range. An engine making 500 lb-ft @ 2K rpm will skyrocket above the other engine all the way to redline. The sissy engine will get it's little tushie blistered. And the torquey engine will cruise comfortably without drama.

What the OP should do is make the plots I suggested earlier. That will be a great launching point for discussion and generating targets and ideas. It's all speculation without the data.

 

Fair enough. I am just going off of my interpretation of the OP's stated goals. He wasn't interested in HP numbers. He just wanted 500@2000 rpm and that is more easily attained with 333@3000 rpm. He would do well to follow your suggestions in your last three sentences.

 

Wow I guess I got everyone curious. :^) And most votes so far are either Yes or Wanting To See instead of no. (even if plenty of text posts indicate no) I can only respond to some of these tonight.

Thanks, yes I see a very similar discussion there!

I'm not trying to reinvent the wheel - this is ALREADY what they do with the Ecoboost. Strong block, strong block-to-head sealing, strong crank, strong rods, strong pistons. The ONLY difference in my mind for the LS is the last two maybe questionable - yet even stock parts aren't radically higher than stock powers in like a 6.0 (and equal to the new 6.6, does that use different rods?) yet they run factory engines for hours...

I know it's easier with more cubes - easiest answer just go Vortec 8100. Why use an Ecoboost either? Altitude compensation, possibly better MPG... so why use a small block? Far more and cheaper cores available, potential upgrade path for people with that engine who just want a little more power, etc.

If the issue is NOT the crank/rod/etc strength then there shouldn't be a problem with what i'm proposing. Thats why i'm asking... and if I DONT have to replace the rods and pistons, even better.

I know it wont last as long, but with $250-500 cores I can afford to care a little less. :-P I never said chinese turbo either, I think I mentioned use an existing diesel turbo, cast iron and made to run hot. Iron heads too even if I lose a little boost or CR potential - looking for lower buck mods for DURABILITY, and a minimum of mods for strength if needed. The Sloppy Mechanics guys already bent everyones minds about what kind of power LS's can take reusing head gaskets and with TTY bolts - in my mind I bet there's alot of pickup guys wanting big block power who are good with a welder and see some of those older diesel turbos in the junkyard starting to get ideas right about now... I want to build this for them. If it breaks it breaks, first attempt would just be going into a shop truck and driven locally anyways like I think I said. We figure out where it breaks, grab another core, and pay closer attention to fixing what dies. If it craps the bed 1000 miles from home, get a tow to the nearest junkyard where you can always find a 4.8/5.3 core (but not always a 6.0 core complete, or for cheap) and at least limp home without the boost - don't even have to change the computer I bet - then re-add the turbo if it still works when you're at home or grab another.

People have hot rodded like this for decades - I just see those $10,000 diesel engine replacement bills and I cringe. Or I see the 8mpg big block mpg figures unladen around town and I wonder if I could do better.

Also I don't see why a 4.8 with some boost should last much shorter than a 6.0 without IF theyre using the same internal parts. The total intake charge at 400lb/ft divided by 8 should be pretty similar on the crank and everything else.

I didn't plan E85 but using water or water-meth on long uphills is no big deal. A little water or blue windshield washer fluid during the hardest point isn't a big cost, bit complexity or a deal breaker - but I need to get thru the rockies preferably not at 35mph with the hazards on.

I'm sure a properly built big block is the best answer or a Duramax, but not all of us can afford to modify or swap in an ideal answer. A duramax will save on fuel and have long durability but it's always electronics or emissions crap that puts them down, and those Allison trans arent cheap either. Yet i've seen project vehicles where someone already removed the big block or diesel for their own things and I find myself thinking "why not throw an LS in there now to get on the road at all, lightly refreshed if I have time, and not if I dont have the time or money to rebuild it, and later put a turbo on it so it's not a dog? And if it breaks like that, I can fix it again for hundreds instead of thousands to keep it on the road."

Heck the starting point is just towing up to 10k lbs with a lesser powered 4.8 or 5.3 using alot of gear and maybe just going 35mph up some hills... that's likely to happen ANYWAYS... your 1980's trucks did it with less horsepower than a 4.8L you just have to go slow in 2nd gear. It's the future thinking and wondering if the turbo is worth adding - nobody HAS to add the turbo, just like nobody HAS to refresh a junkyard pull, but if I do refresh it i'm wondering what parts I can cheaply upgrade while doing so - and then I have the door open to welding up a junkyard turbo kit without a serious bit of extra coin.


I've kind of already thought of all this, it's not about whats best, or better, it's more about "if I wanted to do this anyways what are the weakest points?" I never suggested that an old junkyard pull and a chinese turbo would equal or surpass anything, but I bet a few modifications would do the job surprisingly well for less money than you think. It's okay if you don't think it's a great idea, i'm just picking the brains of other people who would like to see it happen, or who want to adapt hot rodding type knowledge (or even LS's used in other situations like marine use where it's constant high load) to their tow vehicle.


Oh I know it can, the question is how long. It's just like reading the guys who have turbocharged stock engines in their hot rods - maybe theyre putting down 450hp and broke it after 3000 miles, or maybe theyre running 600hp and it's still good after 25,000 miles. But for hot rods we pretty much know what holds up and what breaks and in the LS it's usually pistons and rods it sounds like more than anything, and it's usually due to detonation.

The difference here is just like hot rodders i'm willing to break stuff to learn and then share what I learn for guys who want to do the same. Sloppy Mechanics did things nobody thought possible on stock everything, i'd like to do the same - just for towing - which more guys need more than they 'need' hot rods probably. :) Of COURSE a Vortec 8100 or Duramax is better, or even a 6.0 - I accept that and have moved on. I'm trying to implement a different philosophy because it better meets my own needs of being able to upgrade from bone stock junkyard LS pull to get an older 3/4ton or 1ton chassis back on the road, to refreshing that engine with some upgrades with an eye for future tow, to eventually boosting the power and knowing I can start over from another junkyard pull for a few hundred bucks anywhere in the USofA.


Thanks for the suggestions and yes I know a 6.0 or big block or duramax - I still think I want to try this. I'm planning all those upgrades - coolers, 4L80 or better, etc. Rather spend my money there than "just making power" and breaking it - that is NOT the plan. I know a supercharger will give the torque but i'm more worried about breaking parts or detonation - junkyard turbosystems can be done cheaper for guys who weld. I dont yet weld but that's why this is part project and part shop truck - it's an opportunity to learn! I have to learn on something. It's an excuse to do something useful to me and possibly useful to other guys.

To everyone else, I KNOW a 6.0 or 8.1 or diesel is better - can we move on? :) :)

Had to split into two posts...

 

Finishing what I already composed but was too long - I missed alot of later posts, just trying to finish thoughts.

I'm not going to tow 10,000lbs with an understressed half ton - i'm planning on taking a vehicle already rated to tow 10,000lbs that's missing an engine and just put an LS in there. I see them all the time, including people who wanted a 454 or the duramax and allison so pulled it out of a 1 ton and are now selling the chassis. I've even wondered about taking a Ford Superduty with their troubleprone diesels and trying to hook an LS up to their otherwise awesome 5R transmission which is as tough as an Allison. Nice trucks, bad engine, back on the road for a $500 junkyard LS so I can work with it for awhile, then eventually pull it, refresh it, upgrade a few parts, run it some more, then eventually add a turbo so it's less of a dog.

I'm not worried about the rest of the setup - just the engine durability. Even my comments on '40% more torque for a 4.8L' is only 20% more for a 6.0L which uses the same rods as far as I know... maybe even stock rods are good enough, keep the tune conservative, add water-meth for cooling up the hills and call it done?

None of this is meant to be the "simplest easiest best" solution - lets say it again, since it keeps coming up - buy a 6.0 8.1 Duramax. Maybe if I answer that enough times in a row it will stop coming up. This is going to be my learning project since I wanted to play with LS's anyways and turbos and tuning and all that - just not for a hot rod use but instead doing WORK and towing stuff I happen to need towing anyway. Do I eventually want fun power, sure, like lots of guys, but for now it's about putting an older tow vehicle back on the road missing an engine, and learning about the world of the LS at the same time with an eye towards future upgrades.


Yes and thanks, thats what i'm thinking too. Detonation kills everything so obviously we need to avoid it. Upgrade the parts that take the worst load - however just like the Sloppy Mechanics guys proved we might need less upgrades than everyone thinks, but that means more the rods/pistons as a maybe which might be plenty strong for the actual loads than saving every penny possible. I dont PLAN to totally cheap out, but I wouldn't expect to run as much or any boost if I do. This is at it's core using a slightly underTORQUE but adequate horsepower engine (the 255hp of the lowest 4.8L ever made still exceeds the 235hp of the early 90's 454 TBI) to repower a 3/4 ton or greater truck (or maybe even van) chassis to EVENTUALLY tow heavy bad aero loads thru the rockies if it proves reliable more locally. Once it's on the road, after a few jobs, things eventually get refreshed and some upgrades. Last step is adding some turbo boost. All while learning about LS's, tuning, welding the junkyard turbo setup and other projects over time.

Other posts i'll have to comment on later if I haven't already steered some of the discussion back to the original intent!

 

Did you even read the first post? Here let me help you. He doesn't want to spend 10k and he specifically mentioned wanting BB/ Duramax power out of a 5.3, On top of that someone else mentions how a little ls out towed a diesel...that was the reason for my reply about diesel engines in general. I wasn't being emotional in the slightest...just realistic and factual lol I have a boosted 6.0 S10 and it makes tons of low end torque and I have a roots blown 408 that the only thing left made by gm is the block itself, Everything else has been replace down to billet main caps. Makes over 700ftlbs at the beginning of the dyno pull (3,000 rpm) and over 800ftlbs at 4,000rpms but it costs more than 10k and runs on alcohol. Neither one would be reliable for 100,000 miles in a tow vehicle.

And you can tell me about your experience with diesels just like I can tell you it doesn't align with actual facts, I've been working on cars/trucks for 40yrs now and have experience with everything from lawn mowers to commercial trucks to race cars. I've worked for companies that have dozens of HD trucks and not one has ever had a $12,000 failure or needed major repairs unless someone screwed it up by putting gasoline in the tank. Most of them go over 300,000 miles before they are replaced and rarely do they have major failures, They have pump failures or need injectors and so on but not all at the same time. Pumps are less than 2k and injectors are sent out, Complete long blocks are less than 10k so anyone spending 12k to fix a fuel problem also got the shaft lol.

Back to the topic of a budget twin turbo 5.3..... Sorry, I just don't see him getting 100,000-200,000 mile durability without a complete rebuild with good parts ( Forged pistons/rods at least) and he wants to spend $250-$500 dollars for the engine.... I don't see Chinese Turbo's being reliable for 100,000 miles...and I don't see him getting to the "450-550lb/ft range coming in strong even under 2000rpm for minutes at a time climbing up a hill" He might do it at a higher rpm, Even then I don't see it lasting that long. Towing is a completely different animal, It works the engine harder than what a drag or street car see's. A drag or street car makes a full throttle pull for a few seconds and is allowed to cool down. Towing is high load for minutes at a time and then medium load with no real time to cool down and the heat generated is one reason I see making that kind of sustained torque with boost on pump gas hard to do. Can it be done...probably but not with a junkyard twin turbo 5.3 for 100,000+ miles.

 

I'll say this and then I'll refrain from posting.
Personally I wouldn't even consider the 4.8, In stock form they suck for towing with out spinning some RPMs.

The reason I said to go with the 6.0 over the 4.8 5.3 is not because one has stronger internal parts than the other. They are the same except the 4.8 has a shorter stroke, It's because one will make more power with less boost so you don't have to push the stock parts as hard to make your goal and less likely to have detonation issues because of the lower boost level required.

You mentioned 100-200k reliability and to me that means feeling comfortable hooking a trailer and towing it hundreds of miles without worrying about having issues and not having to compromise to keep it alive to get there. To me that means not impeding traffic on hills because it can handle it without running hot or revving the **** out of the engine because running it under high load with boost at a lower rpm is causing it to suffer from detonation. A bigger engine will be less likely to have issues than a smaller one because they make more torque, More torque means less rpm to achieve the same goal.
If you're just wanting to tow 2-4 thousand pounds like a small camper, 12' enclosed trailer, Small boat or something like that then you don't need 450ftlbs at 2,000rpms to get it done.

 

Based on goals, this isn't going to be a junkyard 5.3 and chinese turbos. Gonna need to spec parts that can handle the load on long grade with a peak tg around 3K. E85 preferred or 93 with -30F ww solvent. You can get BBC tq+ with a thought out combo. Not going to get Duramax tq.

Had a friend looking to put a pd on a BBC 94 2500 Burb to tow a 35' trailer. A functional kit was not available and required significant mods to make work. He punted and bought a 2019 Dodge 3500 Cummins and 35' trailer to haul cars and move household from Ca to Ohio.

 

Whose goals? Not the op's based on his first post as far as I can see. Didn't he state he just wanted around 500 lb-ft @ 2000 rpm?

 

There is no reason this wont work. Timing needs to be conservative, and if you can use a tow mode to pull timing even better. AFR needs to be richer during towing. WMI would be a sweetener but not required. It's all about sizing the turbo correctly for the intended RPM and boost.