Addressing Internet Myths About LS Swaps

Even the iron block LS motors have aluminum heads and plastic intakes. So maybe heavy compared to the all aluminum versions (by under 100#) but still less than any all iron block +iron head combo.

It's all about what you are comparing it to.

One of the best LS swap articles I've read. 

I've abandoned the idea for a performance car due to limited skills, time, space, money, and most importantly, motivation. No gear head friends either.

Still considering one for my GMT400.

Ranger50 said:

In reply to Trackmouse :

And to answer your question about the aluminum block LS, yes it has been challenged. Vorshlag did it in the bmw.

Nope. Though the E30 eventually got a built up aluminum engine, the two times it went to the Challenge it had a budget iron-block engine.

So, in short:

LS swaps are obviously cheaper for fabricators. Not so much for us none fabbing guys. Also, deals can be had if you're fast and vigilant enough. Also, depends on the chassis you're swapping it in. And if you're going auto, t56, or other trans. As well as which LS engine you'll be using. 

My conclusion: LS Swaps are cheap to some and expensive for others. 

I was planning around $3k if I ever did an LS swap in the GTA. Probably looking for a donor 5.3 2wd truck use, stock everything except for an f-body oil pan, a car intake of some description, and front acceories that don't stick the alternator through the hood. Using the 4L60E as well. Car is ending up with a stock tpi 305 for now because every time I look into building the 350 with efi it gets dangerously close to LS swap budget territory. So I'm dealing with no power and putting money into the chassis.

edizzle89 said: Also he said the 4.8/5.3's need a head swap to be decent were a uz doesnt but if i remember right the worst of the truck/van heads still flows better then a 1uz head stock-for-stock.

Not sure I follow your logic on the heads. Look at stock power output of these engines, year for year. The 1uz makes more than any 4.8 I'm aware of, and is quite comparable to the 5.3, despite having more than a liter of displacement less. This likely results in less torque for the 1uz, unsurprisingly, but the hp is there, and having driven a vvti 1uz, I can't say that I feel any particular want for more torque.

Now, perhaps a more pointed question, why bother with the lower end of the LS family? Cheap to acquire the engine, and reasonable torque, is about all I can see the appeal of. However, in a sporting car (this IS GRM, right?), is the weight penalty (of either iron or aluminum 4.8/5.3 variants) worth it for often mild power increases? I would think, in the example of a Miata, that a low end V8 swap is a LOT of work versus a turbo setup that would return similar performance for likely less money, and likely less weight.

Seems like a lot of work for very little gain? That said, I did build a silly Supra when in all reality, I probably should have just bought a C6Z instead... so, take my words with a grain of salt. =P

I could have missed it but I didn't see the complete weight. I think one of the other myths is that it's automatically lighter than all other V8s.

In reply to Tom1200 :

True. The weight of a complete (minus exhaust manifolds) LS1 and T56 combo is well known since Vorschlag weighed it a few years back and posted pics, but the weight of the engine in your car may be significantly harder to find since hardly anyone who does a swap also has a scale which can weigh an engine. Most info you'll find in a search about the weight of any given engine is pretty much useless; it might come from a website with a list of engine weights with little to no info about the completeness of the engine weighed, or it might come from some guy on a forum who didn't actually weigh it himself. IMO anyone who doesn't drive a truck or a muscle car with a heavy V8 already in it should completely disregard the iron block LS architecture engines, and I really wish people would stop calling them LS engines and start calling them by their proper engine codes. True LS engines are aluminum.

609 for the fully dressed drivetrain while the T56 weight can vary depending on version but I'm seeing 115 to 128lbs.

In reply to te72 :

In my case it's a 50-70hp increase(if I left it stock, which I wouldn't). Less weight, better fuel economy, and more room to go up in power with cheap and readily available parts. 

te72 said:

edizzle89 said: Also he said the 4.8/5.3's need a head swap to be decent were a uz doesnt but if i remember right the worst of the truck/van heads still flows better then a 1uz head stock-for-stock.

Not sure I follow your logic on the heads. Look at stock power output of these engines, year for year. The 1uz makes more than any 4.8 I'm aware of, and is quite comparable to the 5.3, despite having more than a liter of displacement less. This likely results in less torque for the 1uz, unsurprisingly, but the hp is there, and having driven a vvti 1uz, I can't say that I feel any particular want for more torque.

 

Now, perhaps a more pointed question, why bother with the lower end of the LS family? Cheap to acquire the engine, and reasonable torque, is about all I can see the appeal of. However, in a sporting car (this IS GRM, right?), is the weight penalty (of either iron or aluminum 4.8/5.3 variants) worth it for often mild power increases? I would think, in the example of a Miata, that a low end V8 swap is a LOT of work versus a turbo setup that would return similar performance for likely less money, and likely less weight.

 

Seems like a lot of work for very little gain? That said, I did build a silly Supra when in all reality, I probably should have just bought a C6Z instead... so, take my words with a grain of salt. =P

I can try to answer that, because I am building a 4.8L Miata. I can share my reasons...

- The 4.8 is an oversquare design. The rotating assembly is smaller. That means it revs better than it's bigger counterparts- very nice for a sports car. 

- The 4.8 has less torque than its big brothers, but still way out performs smaller displacement engines. I don't need huge torque in a 2600 lb car that is street driven.

- The 4.8 is really cheap. 

- The 4.8 is only a cam and heads away from 400hp. Ok, that's not 600 or 1000, but I am building a street driver, not a drag racer. 

- The exterior of the 4.8 is dimensionally identical to it's bigger brothers. That means all the work I do fitting a 4.8 into the car is not lost if I later choose to switch to a bigger engine. Transmission, mounts, exhaust, heads, intake, pan, hood clearance, front cradle will all still work. 

I consider the 4.8 a cheap mockup motor that may offer me all the performance I want, but is easy to switch later.

Trackmouse said:

In reply to edizzle89 :

And I never did. R-E-A-D people. READ. Effing, READ. God, how illiterate can people be?

There’s an old saying, “if one person calls you a jackass, laugh in their face and don’t let it trouble you; if two people call you a jackass, start to wonder; if three people call you a jackass, start looking for work as a pack mule”.  

Food for thought. 

te72 said:

Now, perhaps a more pointed question, why bother with the lower end of the LS family? Cheap to acquire the engine, and reasonable torque, is about all I can see the appeal of. However, in a sporting car (this IS GRM, right?), is the weight penalty (of either iron or aluminum 4.8/5.3 variants) worth it for often mild power increases? I would think, in the example of a Miata, that a low end V8 swap is a LOT of work versus a turbo setup that would return similar performance for likely less money, and likely less weight.

 

Seems like a lot of work for very little gain? That said, I did build a silly Supra when in all reality, I probably should have just bought a C6Z instead... so, take my words with a grain of salt. =P

It's a judgment call. If you're working on a build for a lightweight car that already needs a lot of supporting mods, and don't plan on a wild turbo build, I'd probably shell out a little extra to get an aluminum block. But even an 4.8 can be built to the high 300s if you add the right mods to let it rev, and give a bit smoother power delivery than a high boost turbo four cylinder.

The thing about the LS is not that it makes more power than everything else, but that it has excellent power density. It makes more power for its physical size than just about anything. And that physical size is a big reason people use it. My MG was originally going to get a SBF until I saw a complete LS engine out of the car. The packaging is really well done - and with OE options for interchange, the difficult parts of that packaging can be changed up. With engines that have seen use in a limited number of OE applications, you don't have as many options there.

As for when the work becomes worthwhile - if you're paying someone else for the work, my thought is that the crossover point of V8 vs turbo four on a Miata is about 400 hp. That's the over-simplified peak power number, of course, and ignoring the fact that at 400 hp the rest of the Miata driveline is a grenade with the pin pulled while the T56 and GM rear are snoozing. But if you're comparing peaks, that's where the hp/$ lines cross. If you're doing your own work and buying junkyard parts, I think it would be lower down. They're very different to drive though, just like a 200 hp naturally aspirated four feels different than a 200 hp turbo four does.

In reply to Keith Tanner :

Please describe some of the driving differences. 

Well, here's a starting point.

I've always felt that naturally aspirated cars feel more mechanical and turbos feel supernatural. You feel that turbo whoosh and a big invisible hand pushes the car forward. Meanwhile, with the naturally aspirated engine, you get yanked forward by the force of explosions underhood. This is a generalized personal opinion, but it's got some experience behind it. Superchargers feel mechanical as well, especially positive displacement ones.

But outside that, you can see the tork. Nearly three times as much torque at 3000 rpm as the turbo, and it will deploy as fast as you can move your ankle bone. You just can't get away from that when driving. The V8 is always ready to party.

Depending on how the V8 is implemented, you get other differences. The turbo can hide in the background. I used to love giving customer rides where we'd start off chatting away and I'd drive like a normal car, staying out of boost and even keeping the BOV quiet. Then I'd drop the hammer and the contrast would either shock them into silence or make them laugh like a loon. It's harder to forget about the V8 due to the noise at least. You're also aware that there's more mass in the driveline, the shifts have a bit more inertia behind them when you're shifting slow. But you can drop the hammer at a lower rpm and you will literally bounce your passenger's head off the headrest.  Heck, you'll bounce your own if you're not paying attention.

The ability for the turbo to disappear makes it a really nice highway cruiser or street car. It'll get better mileage around town too. The LS engines work more on a gallons per hour basis, so if you're just noodling around you'll find the fuel economy is pretty tragic. But like I said, always ready to party immediately.

On track, there's less of a difference as long as you can keep the revs up so the turbo is in the fun zone. They'll both kick you in the butt on a 3-4 shift. The V8 lets you be a little more flexible - I've actually done a complete session or two at Laguna Seca with the car left in 4th gear. Once you're used to the power delivery of the turbo, they're easy enough to modulate and they're a bit easier to keep traction out of a corner due to the slightly softer power delivery - the V8 will rip the tires free more easily if you drive stupid.

In reply to Keith Tanner :

Excellent. Thank you. 

In reply to Trackmouse :

What does it take, control wise, to get a 1UZFE up and running in a car without any computer? There's one available locally at a Challenge friendly price, complete with the harness , ECU and transmission. It's from a 1992 SC400, if that's pertinent.

docwyte said:

Having done an LS swap, I can tell you from direct experience that it costs ALOT of money.  Unless you're doing all the labor yourself and custom fabbing up everything you need for the swap yourself, there's NO way you're getting it done for under $10k, with an LS1, 2, 3, 6 etc.

9 years ago an LS1 with all accessories, PCM and wiring harness cost me $2500.  The swap kit with headers, bell housing, motor mounts, hydroboost brakes, cam, radiator, Turn1 PS pump, exhaust etc were at least $6000-7500.  Then labor to put it all in.

I've played with the idea of LS swapping my E36 M3.  Just the needed swap kit stuff from Vorshlag is close to $5000.  Then I'd need the LS motor and T56 transmission, than labor.  So $10-15k.

Yes, you can do it for less using an iron block 4.8 or 5.3, but again, unless you're fabbing up all the necessary swap kit stuff, you're going to spend $4-5000 on that stuff alone...

I barely have $10k in my entire Nova.

That includes:

-Cost of the car after selling off what wasn't needed.
-New floors/firewall.
-New Carpet
-New front seats/seat belts.
-New gauge cluster (6-gauge setup)
-Checkered Racing Front fabricated subframe
-Built 8.8 rear
-New Vision 5-hole wheels, cheap front tires, MT E/T Pros rear.
-4-wheel disc converison.
-4L80e, triple disk billet converter.
-Aluminum LS, with new cam/valve springs.
-Billet borg warner turbo, custom turbo setup, single 4" fender dump.
-Stock PCM/wiring harness.
-Caltrac split mono rears with Caltrac bars
-QA1 adjustable shocks all 4 corners. 

Car cruises on the highway at 70 at 2200 RPM and gets 26 mpg doing it. 
And makes 4-digit power pushing that Aluminum 5.3 with over 20 PSI.

I'm sure its expensive when you're buying pre-made kits and paying someone labor. 
When you piece together the needed components and do your own labor, you get MUCH more car for far less cost. 

Knurled. said:

AwesomeAuto said:

Claim 2: Swapping an LS for an Earlier GM V8 Is a Bolt-In Project

-Most certainly can be. $35 adapter plates allow you to reuse 3-bolt SBC engine mounts, bolting them to your block, dropping the engine in.

 

As long as you don't mind not having A/C.  If you want A/C, you need to move the chassis side engine mount back a few inches.  Or spend a bunch of money for one of those compressor relocator setups.

 

Most people who want to repower an old ride want to keep the A/C.

 

 

A/C brackets can be had from places like ICT billet that allows you to use an old style A/C compression high on the passenger side. In most cases, this will let you retain your factory A/C system without changing anything on GM vehicles. These brackets are less than $200.

Swapping into a different make and wanting to keep A/C will be a little more expensive, but not impossible. There are a couple of brackets that allow you to use the stock LS truck A/C compressor, moving it up higher or even to the driver's side. Your only effort will be in the lines themselves. Drop in the bucket compared to the labor/trouble you'll be doing for certain other aspects of the swap.

AC was the hardest thing for us to work out on a "production" swap. Mating the GM and Mazda systems involved parts that just weren't available anywhere. We did some by taking Mazda parts and having them modified, but between the PITA factor and too much variance in quality we had to have the parts machined. We did the same for the PS, there are some custom fittings in there that you're just not going to find in nature because nobody else wants to put an AN fitting on a Miata rack.

Keith Tanner said:

AC was the hardest thing for us to work out on a "production" swap. Mating the GM and Mazda systems involved parts that just weren't available anywhere. We did some by taking Mazda parts and having them modified, but between the PITA factor and too much variance in quality we had to have the parts machined. We did the same for the PS, there are some custom fittings in there that you're just not going to find in nature because nobody else wants to put an AN fitting on a Miata rack.

Local hydraulic shops are great at making power steering lines, such as Parker. Places that do forklift repair can do them for you too. Take them a line/hose you need with the attachment and you need, like the one going to the rack. Parker has always been good at getting us taken care of.

That's what we did. The problem was that the fittings we needed were not available new, so we were depending on used ones being cut out of old lines. They were not dependable enough. It's the sort of thing you can deal with if you're only doing one, but a lot more complex if you want to be able to ship stuff out to people or you put a value on your time. We eventually had to have those fittings custom made so they could be crimped in.

Keith Tanner said:

That's what we did. The problem was that the fittings we needed were not available new, so we were depending on used ones being cut out of old lines. They were not dependable enough. It's the sort of thing you can deal with if you're only doing one, but a lot more complex if you want to be able to ship stuff out to people or you put a value on your time. We eventually had to have those fittings custom made so they could be crimped in.

Yeah, not every car is as easy to swap as the others. Some can be done in a weekend with enough planning and prep. Others, not so much. 

Keith Tanner said:

AC was the hardest thing for us to work out on a "production" swap. Mating the GM and Mazda systems involved parts that just weren't available anywhere. We did some by taking Mazda parts and having them modified, but between the PITA factor and too much variance in quality we had to have the parts machined. We did the same for the PS, there are some custom fittings in there that you're just not going to find in nature because nobody else wants to put an AN fitting on a Miata rack.

We just make our own lines.  There's a company that makes threaded fitting hose barbs for the common compressor(s) used on these engines (is there even more than one?) which makes creating generic hoses simple.  Alternatively, you could TIG up something.

Da Boss's dad bought a Solstice GXP specifically to install an LS3.  He had to take the rack and pinion and move one of the ram lines to the 3 o'clock position instead of the stock 12 o'clock position that interfered with the damper.  He disassembled the rack, TIG'd the old hole shut, drilled and tapped a new position, and made a new ram line.

This was, to my understanding, the only significant alteration to the chassis needed to make a LS3/TR6060 combo fit.