5.7 vortec vs 5.3l or 6.0 swap

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Erik the Awful

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modified to modified depends entirely on intended use and budget.
This. I don't care about comparing stock to stock. The LS is a superior architecture, but it's also still more expensive. Building for torque is cheaper than building for horsepower. If you're building for torque, go with a 350. If you're building for all-out horsepower (sorry, L31MaxExpress, LS heads flow better), go LS. Anywhere in between it's your own calculus of what power level you want at what rpm and how much money you want to spend.
 

L31MaxExpress

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This. I don't care about comparing stock to stock. The LS is a superior architecture, but it's also still more expensive. Building for torque is cheaper than building for horsepower. If you're building for torque, go with a 350. If you're building for all-out horsepower (sorry, L31MaxExpress, LS heads flow better), go LS. Anywhere in between it's your own calculus of what power level you want at what rpm and how much money you want to spend.
For the record, my 23° ~210cc heads flow about what stock LS3 heads flow and could have gone much further if I had not stuck to a Felpro 1255 and factory Vortec exhaust manifold port dimension and location. Chad Spier has a CNC program that makes these same castings flow something like 330 cfm from a 227cc port.

If I could go back and change one thing on my 383 build, would be more cubic inches. In the form of a 1-piece rear seal, 350 main, factory roller cam compatible 4.125" bore Dart SHP block and a 3.875" stroke crank.
 
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Yardawg

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Assuming you have a NV4500 absolutely. In normal driving without the trailer you will find yourself launching your truck in 2nd gear.
Not sure if mine is the nv4500 but I can say the 1st gear is already "granny" gear so I start out in second gear now
 

90west

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It's as easy as this...just follow the numbers if you are towing: 4.3<4.8<5.3<5.7<6.0<7.4<8.1. See a trend? Assuming all are stock, Vortec (SBC and LS Gen III) and naturally aspirated.

Axle gearing and transmissions adds a bit of complexity to the game, and can really help or hurt; but generally, more cubes = better towing experience. It's as simple as that. HP/TQ curves are good to look at too. Insert the 383 in that list accordingly, but that wasn't a stock option for these trucks. I'm not sure where the 5.0 Vortec (never really hear about those anymore) and TBI-series fall in the list though, but probably irrelevant to OP's question.

I think the only direct apples-to-apples comparison would be a 5.7 LT1 ("Gen II") to 5.7 LS1. Seems not much out there on the LT1 anymore though... something about Optispark or something? Dunno. :rolleyes:

Did OP ever chime back in? It seemed he was more interested in building his 5.7 Vortec and firsthand experienced from guys that had done that. So are spinning our wheels and arguing for no reason, LOL. Run whatever engine makes you happy. There are no right or wrong answers. Everyone is correct in their mind.
Didn’t realize this thread was still going I’ve been working and putting my truck to work as far as the engine swaps go I was just looking at apples to apples comparisons meaning if I had a hypothetical $3000 budget is it better to build the stock motor or swap in a different engine I have a 2020 with a 5.3 and it tows ok but at the end of the day the 97 is my current work truck so building a boosted 5.3 with a bunch of go fast parts isn’t really practical considering reliability sits very high on my list and being a full time mechanic the last thing you want to do is be tinkering with your own rig instead of working on customers rigs
 

stutaeng

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Thanks for chiming back in on budget.

This is my advice and probably last post: Doing an engine swap is going to take time. Are you doing the work yourself? You need to do a lot of research on topic. The good news is that LS swaps have been swapped in just about anything, and the GMT400 is probably the most swapped truck they go into. Maybe you can drive the 2020 until yours is back up if you decide on it.

I would highly recommend a LQ4/4L80e swap. You won't be disappointed. Get it as a combo with ECU and all accessories. They usually go for around $2500 here, but sometimes you can get good deals. I saw one the other day for $1500! You'll need to add another $1,000 to $1,500 for miscellaneous things to complete the swap though. There's different way to do things on the wiring/electronics.

My mason has a 2500HD with the 6.0 and dude works it hard, towing brick, CMU, sand, etc. Just about all of the older work trucks in construction and landscaping around here pulling trailers are GMT800/900 2500HDs, the majority of them with that combination. It's starting to become rare seeing any GMT400 8 lugs anymore as work trucks.

As I mentioned earlier, the Gen V has about the same power as the older LQ4, and the K2XX is heavier than the GMT400, so you can imagine it will be a good combo for your 97 since you have driven both. Reliability? Stay stock. A Gen III is pretty reliable. Not much to go wrong with them. 4L80e is a joy to drive. Pretty dang tough, reliable units. On a power/durability to dollar ratio, you can't beat the LS/4L80e.

Keeping your engine will have an advantage of truck not being down for upgrades. Headers, cam, and exhaust, etc. are pretty common upgrades. If you opt to punch out the block or open it up, then again truck will have downtime. Then you have to be weary of your 4L60e: they are not too reliable for working them hard on a daily basis. Throw some big power at them in a heavy truck towing regularly, and you'll need to upgrade sooner rather than later. It's gets spendy after a while rebuilding them.

I hope this helps and good luck. Whichever way you go, consider doing a truck build thread. Well all like those here. :)
 
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L31MaxExpress

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Thanks for chiming back in on budget.

This is my advice and probably last post: Doing an engine swap is going to take time. Are you doing the work yourself? You need to do a lot of research on topic. The good news is that LS swaps have been swapped in just about anything, and the GMT400 is probably the most swapped truck they go into. Maybe you can drive the 2020 until yours is back up if you decide on it.

I would highly recommend a LQ4/4L80e swap. You won't be disappointed. Get it as a combo with ECU and all accessories. They usually go for around $2500 here, but sometimes you can get good deals. I saw one the other day for $1500! You'll need to add another $1,000 to $1,500 for miscellaneous things to complete the swap though. There's different way to do things on the wiring/electronics.

My mason has a 2500HD with the 6.0 and dude works it hard, towing brick, CMU, sand, etc. Just about all of the older work trucks in construction and landscaping around here pulling trailers are GMT800/900 2500HDs, the majority of them with that combination. It's starting to become rare seeing any GMT400 8 lugs anymore as work trucks.

As I mentioned earlier, the Gen V has about the same power as the older LQ4, and the K2XX is heavier than the GMT400, so you can imagine it will be a good combo for your 97 since you have driven both. Reliability? Stay stock. A Gen III is pretty reliable. Not much to go wrong with them. 4L80e is a joy to drive. Pretty dang tough, reliable units. On a power/durability to dollar ratio, you can't beat the LS/4L80e.

Keeping your engine will have an advantage of truck not being down for upgrades. Headers, cam, and exhaust, etc. are pretty common upgrades. If you opt to punch out the block or open it up, then again truck will have downtime. Then you have to be weary of your 4L60e: they are not too reliable for working them hard on a daily basis. Throw some big power at them in a heavy truck towing regularly, and you'll need to upgrade sooner rather than later. It's gets spendy after a while rebuilding them.

I hope this helps and good luck. Whichever way you go, consider doing a truck build thread. Well all like those here. :)

I weighed the same options, even had a LSA blower for the low mileage 6.0L I have. I decided to build a Gen1 based 383 and I am glad I did. Far more torque than a 6.0L and it will live a very long time. I decided against boost for a reliable tow rig.

The 383 just put down 399 rwtq @ 3,100 and 382 rwhp at 5,600 uncorrected on a Mustang dyno through a 4L85E and GM 10.5" 14 bolt FF. It made more than 370 rwtq from 2,500-5,200 rpm. It was 102F, 38% humidity and 29.70 in/hg barometric pressure in the shop at the time. STD correction factor was a 1.079. If you believe in a correction factor it put down 430 rwtq and 412 rwhp STD corrected. The 383 ran for 5 hours and was subjected to no less than 30 pulls and the ac ran the entire time. The 383 never got over 185°F and the trans never went over 160°F.
 

0xDEADBEEF

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How do you define "far more"?

My 5.7 LS1 made about 400 torqs at the wheels. I don't think that's an impossible number for a 6.0 at all.
 

90west

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I weighed the same options, even had a LSA blower for the low mileage 6.0L I have. I decided to build a Gen1 based 383 and I am glad I did. Far more torque than a 6.0L and it will live a very long time. I decided against boost for a reliable tow rig.

The 383 just put down 399 rwtq @ 3,100 and 382 rwhp at 5,600 uncorrected on a Mustang dyno through a 4L85E and GM 10.5" 14 bolt FF. It made more than 370 rwtq from 2,500-5,200 rpm. It was 102F, 38% humidity and 29.70 in/hg barometric pressure in the shop at the time. STD correction factor was a 1.079. If you believe in a correction factor it put down 430 rwtq and 412 rwhp STD corrected. The 383 ran for 5 hours and was subjected to no less than 30 pulls and the ac ran the entire time. The 383 never got over 185°F and the trans never went over 160°F.
 

L31MaxExpress

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How do you define "far more"?

My 5.7 LS1 made about 400 torqs at the wheels. I don't think that's an impossible number for a 6.0 at all.
Was it spinning a 4L85E and full floating 14 bolt? That is ~25% drivetrain loss. I also highly doubt your LS1 came anywhere close to making 400 rwtq at 3,100 rpm. I bet it made its torque closer to 4,500 rpm.
 
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