I have a third gen firebird which I am doing an LSX swap for. I was wondering if the 5.3 liter is a viable option. I know the same amount of power can probably be had in a 5.7 liter or 6.0 liter engine, but those engine are fairly hard to come by in my area for a reasonable price. I've seen some 5.3s for about 800 bucks and the aluminum block ones for a little more the 1K. Would this be a viable or wise choice for my engine swap, or am I wasting my time?

 

I say go for it. You can swap the dished 5.3 pistons out for some 4.8 flat top pistons, and bump your compression up to about 10.5:1 with the stock heads. I myself am doing this swap (I've actually just started collecting parts) in my 68 Chevelle. Since the car originally came with a 327 (that's long gone now), I thought the 5.3 would be an awesome swap! I'm also doing it to be different. Everyone says the 5.3 is a waste of time, there's no replacment for displacement, etc... I say Bull to that, I'll have just as much fun with the 5.3.

I bought a 4.8 for $207, but then I had to pay an extra $250 to ship it from Florida, so $457 all together. 4.8 & 5.3 use the same block, just different crank rods. 4.8 pistons are flat tops, while the 5.3's are dished. I'm plan on getting a forged crank, and rods, so there was no reason for me not to buy the 4.8. There is NOTHING along the lines of LSx engines in my area, so I figured $457, including shipping wasn't a bad price for a running engine...

That's just my point of view. Don't let the "no replacment for displacement" guys stop you.

 

The 5.3 will beat the pants off of what you have in there now.

 

That's for sure! the 2.8 v6 that's in there now could be described at best as anemic and asthmatic. My daily driver '02 accord (I know, I know an import, but it's reliable and a stick shift) can kill it. Anybody have any numbers for the 5.3LSX, 1/4 mile, 1/8 mile or 0-60 times? I also, eventually hope to turbo charge it because I love turbos. Also, what about a T56? Swappable onto the 5.3? .

 

do it. easy to upgrade as well.

i am doing a 5.3 in my caprice wagon. i have a huge turbo sitting here by the desk that i could always go to later.

 

i have a 5.3 in a 89 mustang made 350rwhp engine and run 12.3's on engine spinning bad. mine has a victor jr intake and a carb with home built ignition system, run 11.2's on 100hp nos, i aslo have a 86 300 zx that i'm currently working on that is going to be turbo charged. also all most parts interchange

 

The 5.3 is just as strong and in stock form you will barely note the diff from that and a stock LS1 expect in the top range.

LS1s cost too much due to prestige. Save some money get the LM4 5.3 AL from the SSR with has a LS6 block debored anyways. Just pop on a LS1 intake oil pan and other acc/brackets and you just got 95% of the performance for a bargin cost. Put in a 2004 Z06 cam and you will get more than that 'lost' performance back.

When I was looking for a new motor I found an ALMOST NEW t/o LM4 for the same price as a wrecked LS1 with 80k miles on it. Obvious decision.


Go put all that money you are going to save into an account!!

 

Drop the 5.3L in there. I did because it was cheap, but with a performance tune it puts out 250hp at the wheels. Its good enough to run 13.8`s @97 and gets better fuel mileage than the 305 that it replaced.

The T56 can be put behind a 5.3L, but at that point you should probably start comparing your cost savings. If you run a 5.3L truck motor you will need to switch to a f-body oil pan and exhaust manifolds, the alternator will not clear your hood so you either have to get a hoodscoop, build a new alternator mount, or change over to a f-body bracket setup and accessories. The truck motors will be cheaper, but if you can`t find used oil pans, exhaust manifolds and accessories so you have to buy them new the cost savings will be eaten away at.

 

So, I've been hearing that I could get ~400 hp from the 5.3 with heads, camshaft, LSX intake (like FAST) and a decent exhaust system. Does this seem accurate or is it just more people who act like they know what they're talking about, but in reality couldn't identify a TPI from an LT1 let alone an LS1.

Also: Stroker kits? Worth the money or should I just go turbo? And as funds won't allow it at the moment (but they will eventually), any more numbers for 5.3s without major internal mods or major weight reduction mods to the vehicle they reside on.

Lastly, I;ve had some bad experiences in forums lately with people scoffing at the idea of doing something even a little different (I.E, 'why would you go 5.3, just save up the money for LS1,2,6,7' and they make me want to throw some sort of incendiary device at them).Just want to let everyone here know that they have been extremely helpful and considerate of a somewhat less than mainstream project.

 

my 5.3 has a 224 with 566/568 114 cam with 2.00 intake valves, completely stock bottom, a little port work 350rwhp, that equals more than 400hp at the flywheel, no stroker kit yet, you have to have custom pistons, go with a turbo at 8-9psi you will have 500+ rwhp, that is my next step, i use the stock truck pan on both my cars with 5.3 with no clearance issues

 

I'm pretty sure Eagle makes a stroker kit for the 5.3 that would take it to 347ci. It runs for a little over 2.5K...

 

I decided on a 5.3l for the 62 wagon we recieved this weekend for performance vs. price vs. availability.



I picked up this 01 5.3l 4l60e with all acc, the o2 sensors, wiring, manifolds, and ecm for $1500 this weekend. It has 62K on it. They had one with 35k but had been disessembled.



I hope it will be a good swap for the wife's DD. But, all those wires scare the crap out me.

 

understandably so. However, I think if you look at a wiring diagram and pick up a wiring harness from Painless, you shouldn't have too much trouble. Popular Hotrodding did a story about LSX engines called "Swap an LSX into anything", it was, I think, June of '06.

 

Ya, there are a lot of wires, but trust me, if you use the underhood fuse block that was in the donor, there are only a couple wires that you will need to splice into the old wiring harness. Take a look at this thread. I detailed exactly which wires need attention...

 

pete, i've got your thread bookmarked on the 5.3 harness to make it stand alone.

but what did you do for the diagnostics port?

 

a 5.3 with cam(571/578 lift) and headers with stock injectors------413hp___ same motor with heads,cnc ported(milled down to 57cc'c,62 stock)10:1 com.631/631 lift cam,30lb injectors,FAST intake,----458 hp.CAR CRAFT Nov. 04

 

i'm dropping an aluminum 5.3 in my 68 camaro. looked long & hard # ls1's & 2's. the 5.3 was just too much of a bargain to pass up.

 

Thanks jeepinpete,

The older wagoneer was another vehicle my wife was lookin at. If this 5.3 goes well and I keep my 72 Jeepster Commando project, I may consider a swap for it.

 

This is probably a stupid question, but will a T56 from a mustang bolt to the LSX with the proper bellhousing, or is everything just too different?

 

Awesome idea! I did the same thing, I picked up a low milage 4.8 and gutted it. I bought an LS1 crankshaft and you can bore the block out to a 3.9 bore so you can purchase LS1 pistons instead of getting expensive custom ones built for you. That, some forged rods, a little block filler to be on the safe side and your good for AWESOME power numbers (as far as strength). And since it is now an iron block 5.7, throw some boost at it and your making some sweet power. So far I have less than a grand in my motor and it has LS1 crank, 241 heads, accessory brackets, LSx intake manifold. boring it out will run around 250-300 and then buying the forged pistons and rods for it and I'll still be under 3K and have a complete motor with forged internals and all for less than a LS1 on ebay lol