L31 5.7 or newer 5.3 Vortec (pics of truck progress included)

[NastyNate32]

I bought a 97 vortec/4L60E combo off a guy but the motor is no good and I've already bought a harness and ECM for $150. My options are to either buy a crate motor for the 97 which is $2000 for a long block from Summit or Jegs, or take my chances with a newer 5.3 L from a salvage yard or individual. I've found a few of them for sale as cheap as $600, most have about 120k miles on them.

What's the benefit of going to a newer 5.3L over buying a crate motor for the older 5.7L? I had the motor and transmission already mocked up and everthing so the mounts are already there for my older vortec. Just looking for some sage wisdom here...

Here is a few pics of where I'm at btw for you picture mongers like myself. It's a former longbed, dropped 4/5:

[hugger6933]

Now the 5,7 and 5.3 are two totally different animals the mounts aren't the only difference the wiring and ecm you have is not gonna do you any good either. Of course I sure you could probably sell it to someone wanting to do some sort of a swap too. I think the 4.8 [why does everyone discount them so quickly?]and the 5.3 make a nice setup to have, I also think the 5.7 just looks at home there like it was made to be there, oh wait it was.While your shopping ask around about a 4.8, they are normally cheaper than the 5.3 [I know mine are]. Also unless you see the vin number stating it is a 4.8 or a 5.3 there are very few times driving a chevy[or GMC] truck when you could tell the difference. Add a custom tune[witch all flashed pcm's have ] and it is even harder to tell the difference with the exception of gas mileage.One more thing For you to think on the trans you have now the 4L 60 E will not work with the 4.8, 5.3 or 6.0. Those trans were different in the length of the input shaft and the torque pump drive was different. It will bolt up but upon cranking the trans will make a horrified squeaking noise and then puke a bunch of trans fluid on the shop floor. Don't ask me how I know this[ it wasn't me but he wouldn't listen to me]Whatever path you choose have fun and enjoy. Jim

[68C15]

Given the situation I'd go for a crate 5.7 and enjoy life

[NastyNate32]

Thanks guys. Jim I've read countless forum posts where you have replied and I definitely respect your opinion. I see you are from Arkansas (I'm from far NE OK). You sale engines/trannies? Do you know much about the 5.7 vortec? The crate one comes with a hydraulic roller cam but I think from the factory it was a flat tappet...not sure how much coherence that would make. Btw I'm making this a daily driver type truck.

[NastyNate32]

That's what I'm leaning toward to 68c10. But I see a ton of people using the 4.8 & 5.3 but hardly ever the 5.7.

[Heavymetl]

Originally Posted by NastyNate32

That's what I'm leaning toward to 68c10. But I see a ton of people using the 4.8 & 5.3 but hardly ever the 5.7.

The 4.8 and 5.3 are typically called "LS" engines.

The 5.7 Vortec truck engine is a typical small block Chevy with the excellent "Vortec" heads that were the pinnacle of production SBC heads.

Completely different engines. The 5.7 "LS" engines were either the LS1 or LS6 variants produced in Camaros, Vettes, CTS-V's, GTO's, etc from 1997-2004. The 5.7 had updates along the way in blocks, rods, heads, and intakes during the production run.

Oh yeah...and the "LS" is awesome.

[NastyNate32]

Originally Posted by Heavymetl

The 4.8 and 5.3 are typically called "LS" engines.

Completely different engines. The 5.7 "LS" engines were either the LS1 or LS6 variants produced in Camaros, Vettes, CTS-V's, GTO's, etc from 1997-2004. The 5.7 had updates along the way in blocks, rods, heads, and intakes during the production run.

Oh yeah...and the "LS" is awesome.

I have a 97 Z-28...it's my second one. Those are excellent motors. I would yank it out and use it but I'm selling the car. It's in mint condition so I hate to rob the power plant.

[Heavymetl]

Originally Posted by NastyNate32

I have a 97 Z-28...it's my second one. Those are excellent motors. I would yank it out and use it but I'm selling the car. It's in mint condition so I hate to rob the power plant.

The 1997 Z28/Trans Am/Formula were LT1 engines. Still based on the classic small block Chevy, but with the optispark, reverse flow cooling, and other features. Good engine, but pales in comparison the the Gen III/IV "LS" engines.

[Nitis]

Is the engine you got not rebuildable?

Also I assume you plan on setting it up to run with the fuel injection cause if not it might be better to lean towrd the 5.7

I am currently stuck trying to dedcide what to do with my k10. I want to do an LS but I don't want to swap the crossmember but to do an LS I have to. HArd to find a lower mileage 5.7 vortec to swap so my hands are tied. Guess I will worry about it when I have some money

[jborders]

I have a 5.3 vortec and it's been great. Obviously the sbc engine is time tested and proven to be a great engine but the ls series engine are also great . The heads are far superior to any stock gen 1 head. Also they have much better sealing you hardly ever have any kind of leak with an ls engine. It's really just what you want in the end can't go wrong either way.

[67 chevelle]

if you have allready mocked up the ls engine i would stick with it , they offer many advantages over the gen 1 small blocks , lighter , stronger, dont leak , fuel injection , and the list goes on . if you have the harness and computer from the ls , stick with that type of engine as they changed slightly over the years , if you dont have the harness and computer , look for a "pull out" engine that comes with them

[Cobalt964ruf]

5.3 my vote

[MARKDTN]

With the situation you have, I would find another Vortec long block or fix the one you have. Vortec is a good engine. It is a pretty easy swap mechanically because it is a physical same size swap. It will bolt in, same exhaust, bellhousing, etc.

If you hadn't already bought stuff to go that way, I would buy an LS. My '01 Tahoe had 163K when I bought it and is now over 270K. Oil is still brown at 5K changes. Never had a starter, alternator went 199K, water pump went 253K.

[67 chevelle]

after rereading your post ,sorry, I see you had an l31 , an excellent engine , and available in long block form for less than $2000 last I checked , . If you have the top end and accesories from that engine , plastic intake and all , its a great engine .

[Bigdav160]

So what's wrong with the L31? Other than leaky intake gaskets and troublesome fuel injectors, they are extremely reliable. I'm sure your's could be repaired on the cheap.

[NastyNate32]

At the least it needs a new crank. I've had some people tell me that as bad as my bearings looked then it likely needs cam bearings, rings, a complete rebuild. Makes me worry about the heads to. I don't want to have$1200 rebuilding it to have it blow up on me when a new one or used 5.3 is $2000. The previous owners must have changed the oil every 60,000 miles whether it needed it out not.

[67c10rustbuket]

I have the L31 because... it was cheap, well technically free once I parted out a wrecked '97 Tahoe. The L31 vortec 5.7 DOES have a roller cam from the factory and came in 96-98 CK trucks, thru '00 in SUV, and as late as '03 in express vans. The benefits I would say the exhaust and motor mounts, no guessing. I see a lot of LSx swaps spending hundreds or more ++ on mounts, sliders, perches, headers, new driveshafts, trans crossmembers... and they struggle to get a good fit. Once they do fit you have to swap accessory brackets or clearance brackets, clearance frame, or just toss the AC compressor.
I am not knocking the LSx, I love them and drive several but for cost comparison the L31 wins for now. For now? yes because well the L31 kind of obsolete isn't it. But cheap, reliable and readily available. The Cons of the L31 from my experience, Gaskets are expensive, there is no $40 full engine gasket set(get your wallet ready!) The injector assembly has limited performance, expensive to upgrade or replace. You cant really upgrade (size) just upgrade to the improved style.
If I were starting from scratch I would go with an LSx, 4.8 or 5.3 either will kick the L31s booty. The L31 just fell in my lap so I went with it.

[neal64ss]

I searched around and found a 5.3/4L60e for my chevelle a few years ago. Got engine, trans, accessories, wiring harness, & PCM for $1250. In my opinion these engines are by far the best VALUE you can get. A similar combo is what I will be putting in the 68 C10 I am getting ready to restore.

[Lees68GMC]

Put a 2005 5.3 4L65E combo in my 68 and absolutely love it.

Great mileage & quick with only K&N, cheap exhaust ($29.00 each Thrush Flow-master rip-off mufflers) and performance reprogram. There are 4 of us friends locally that all have Vortecs in 1-67, 3-68 SWB fleetsides, 1-GMC (mine) and 3 Chevys

[stsalvage]

From what i hear them engine combo's are in High demand.

One ?.I had most guys are now no longer using the AC or heater core systems Most of them take the Heater or AC units out and patch up the fire wall and make a box where the computer slides in to a box so its protected firm dirt oil and water.then put the Vintage AC and Heat units in.Then your Done.

Just asking a ? did you use the factory harness from what ever you pulled it from.I hear the pain less is not a good step to use.I hope in a little while to put them engine Combos in most of my trucks the 5.3 and the 5.7 even the 6.0 be cool

[hugger6933]

The 5.7 used are bringing MORE money than the 5.3 because they are nearing their life cycle end maybe or the ls is a better power plant. The 5.7 is 50+ years old with updates but is great and that is what I would be putting in my truck if I were in your shoes. It is true that the L31 is a roller engine you may have been told about some of the other ones the TBI engine they were not. The money you could/can save by going back with the 5.7 is huge and the tranny thing is still nagging me. Jim

[hugger6933]

I have a rule that I don't use this site to drum up any business because I haven't ever paid the fee so I don't feel it fair to those that have. Jim

[gjmath01]

Originally Posted by hugger6933

Now the 5,7 and 5.3 are two totally different animals the mounts aren't the only difference the wiring and ecm you have is not gonna do you any good either. Of course I sure you could probably sell it to someone wanting to do some sort of a swap too. I think the 4.8 [why does everyone discount them so quickly?]and the 5.3 make a nice setup to have, I also think the 5.7 just looks at home there like it was made to be there, oh wait it was.While your shopping ask around about a 4.8, they are normally cheaper than the 5.3 [I know mine are]. Also unless you see the vin number stating it is a 4.8 or a 5.3 there are very few times driving a chevy[or GMC] truck when you could tell the difference. Add a custom tune[witch all flashed pcm's have ] and it is even harder to tell the difference with the exception of gas mileage.One more thing For you to think on the trans you have now the 4L 60 E will not work with the 4.8, 5.3 or 6.0. Those trans were different in the length of the input shaft and the torque pump drive was different. It will bolt up but upon cranking the trans will make a horrified squeaking noise and then puke a bunch of trans fluid on the shop floor. Don't ask me how I know this[ it wasn't me but he wouldn't listen to me]Whatever path you choose have fun and enjoy. Jim

Hugger..I have a 69 c10swb I have a 98 vortec 350 with tranny im putting into it.my question is do you know if the 4L80 can go right in with the engine? Any mods need to be done and if not what is the best choice to use.

[69Rumbler]

Here a picture if my baby 2012 5.3 w/ 6l80 I love it