been researching and thinking about ls swap, since thats all i ever hear about anymore, but i have a few questions
1 will my md8 700r4 transmission work with a ls swap?
2 is it best to find a 4th gen for the swap?
3 is it too much to swap from a truck ls?
4 how easy it to make 500 hp from the ls engines?
5 and final, 53 or 6.0, whats the way to go?
im old school, and dont know much about the ls swap? but im sure this forum and you guys could help me through it....
any help or advice on these swaps? pros and cons?
thanks alot guys

 

1. Sorta. The LSx ECMs are all set up to control the transmission since all of the ones they came with are electronic. It can be tuned around though.
2. Not really, although some parts (oil pan comes to mind) need to come from that platform. OTOH 4th gen accessories don't fit our K-member without serious modification. The Vette accessories fit better. Truck ones also fit except for the high-mount alternator in some situations.
3. Not at all. Very popular. Needs a 4th gen extension housing for the transmission though, and/or a "swap" crossmember.
4. Ridiculously easy. Esp from a 6.0 or bigger.
5. See #4.
6. Spend LOTS of time on the LT/LS subforum. Don't ask questions yet; just read, read, read, read, and read some more. Any question you can possibly ask is already answered there. Also check ls1tech.com and performancetrucks.net for an absolute wealth of information from the point of view of the motors as opposed to the POV of this chassis.

 

would it be best just to get a different transmission?

 

Here is a link to the LSx swap forum where you can connect with more people that have done the LS swap.

https://www.thirdgen.org/forums/ltx-lsx/

The 4th gen Camaro accessory drive is actually the best fitting but is obsolete and getting difficult to find. The price on those has sky rocketed because everybody with an old muscle car wants those brackets. Our cars also will accept the Corvette brackets and that has pretty much become the go-to for most people and is what comes on GM crate engines. Both require cutting the k-member to make room for AC compressor, but the Corvette makes you cut out even more and the AC hose gets super close to headers. There are aftermarket brackets that relocate the AC compressor so you don't have to cut the k-member.

https://www.thirdgen.org/forums/ltx-...nt-engine.html

Our cars aren't very accommodating to the various oil pans, you'll need to get certain kinds,

https://www.thirdgen.org/forums/ltx-...ls-engine.html

You'll need a new trans crossmember. Choose one that gives space for exhaust to tuck up high in the tunnel (most don't).

https://www.thirdgen.org/forums/ltx-...ls-engine.html

 

Not that easy with the 5.3L despite the legends of folklore. Naturally aspirated 5.3L is good for a peppy cruiser but you're not going to win many races with it against modern cars. It is very popular with the turbocharged crowd though because the smaller bore and thicker cylinder sleeves hold up well to high cylinder pressure.

The 6.0L and 6.2L make a lot more torque and Hp. Those are engines of choice for people that want 500+ Hp naturally aspirated. And it will still drive darn good at that level too. The LS7 is the king of naturally aspirated engines but it is expensive.

This thread show trends of what to expect with each engine type and what people did to get there,

https://www.thirdgen.org/forums/ltx-...o-results.html

 

Most of the Ported Stock Cylinder-Heads will support over 2HP Per Cubic-Inch, with enough RPM (Naturally Aspirated).
(650HP+ from a 5.3L).

From a few Decades (by now) of building these; I recommend not surpassing 100HP per Liter, if a Power-Adder will be added at some point.
(530HP Naturally-Aspirated, if adding a Power-Adder).

I have found that de-Tuning/ removing Power from these Engines down to the Numbers Above...
Greatly extends Engine Life.

If you do not care about Engine Life...
Send me your 5.3L and I will send it back making around 750HP @11,000 RPM.

 

The smaller Bore of the smaller Engines actually becomes one of the main limitations to producing Power.

To keep things simple... Valve Shrouding becomes an issue.
Power Adders can greatly make up for this (but not correct it, of course).

 

I'm surprised to still see these kind of question, grats on potential upgrade


First, figure out the transmission. A 4l80e is the only thing that is going to stand up to daily drag-style launches from every stoplight reliably for 100k+ miles at 500rwhp-800rwhp.


And there is no way no how I would put a 4l80e behind an Naturally aspirated rig.

Therefore I think the most logical thing to do is decide if the car will be a performer, or a driver.

If you just want LS reliability and will be happy with a reliable heavy car ~370rwhp (350-450bhp) would be my suggestion, a 4l60e/700R4 can do that with trans-go mods easily, use a 9.5" converter from Yank as the heart of the combo. The most important part of a performance car is the transmission setup so nailing this is the key to getting a swap to win. You might want to become a 4l60e expert and build them yourself at this level and when you get good enough you can turn up the wick to 500-600rwhp through a 4l60e is possible, but only after you learn the 4l60e and master its features. On the other hand budget permitting you can simply buy a proper built 700r4 but they are pricey around $3000? (700r4l60e.com or clinebarger are the only two I recommend to buy from) and commonly damaged during installation creating very expensive mistakes potentials to avoid. The 4l60e is the ideal transmission for performance because it has light weight parts inside, so it can economy cruise nice and low rotating mass allows it to speed up easily and not absorb so much energy from the engine during acceleration. The problem is, the 4l60e is difficult to build, you really need to become a master of not only assembly but also tuning the transmission. It can become a potentially costly learning curve for cars that are actually being used everyday and not a dream on paper still or being 'built' somewhere.


Performer wise, the bar is set up near minimum 700rwhp these days. To be anything or anywhere near or close to what the newest best stock vehicles can run in the 60k to 200k price ranges? After all, the whole point of building a 'power house' in the first place is to do it at a fraction of the cost, maybe spend 20k instead of 100k to get the same performance and reliability.
Try to budget 20k before starting no matter what you decide to build.

The engine you probably want most is
The engine you want for simplest most reliable and turbocharged-powerful swap, is an L33 from 05-07' Trucks
The L33 is a record holder for stock bottom end capability (well known)
Aluminum, light weight and can easily 1000rwhp daily driver if you are a tuning master.
it uses gen3 electronics which are the most basic, plentiful, well known, easy to swap and tune of all the LS platforms.
The L33 has gen4 internals which allow the 1100rwhp~ output (search world record L33 engine or something)
It is still a great choice for low weight, robust 'truck' engine, many miles of service no matter how much power it has

If you need a free engine instead (much easier to find), the LM7 is plentiful and I have gotten several of them free, but they are IRON so +120lbs makes a big difference there, and Gen3 internals which for many claim are capped near lets say 700rwhp although tuning makes a big different with power caps because pressure applied to a piston is done over some range of connecting rod angles which means large pressure spikes near TDC positions can yield rod-crushing force with very little torque output result to the crankshaft.

Get 140,000miles+ used, higher mileage is better, looks clean inside with high mileage is a sign of maintenance and filtration. The key to high mileage is great air filtration and fully OEM style PCV system, crankcase monitoring and control. A high quality paper air filter and pre-filters (a filter cover or pre-filter panels) are what I recommend. A drop of 1.5" Hg between air filter and compressor wheel is ideal at WOT to drive crankcase evacuation, e.g. some filter restriction is necessary & desirable to use a turbo as a crankcase scavenging pump. This is how all factory turbo cars are setup and necessary for high mileage and clean engine, no leaks.

Instructions for best success
Do not take the engine rotating assy apart no matter what
Only perform cam/spring/lifters/pushrods/chain/gaskets, and general cleaning.
Do not port or modify LS factory heads
Keep a spare set of heads in case your main set have some issue (a bad thread for example seems common)
Never machine the block or heads. Do not change or touch cam bearings.
Always wear new gloves before touching engine internal parts and never leave engines 'open' to the air for longer than needed to do a job quickly.
If buying new heads make sure they are not shaved or machined. Only use the LS heads that accept the MLS Metal OEM Headgaskets.

Both engines LM7 and L33 can easily 600 to 700rwhp at 18-22psi of boost through a 4l80e on 93 octane alone with proper intercooling (I see and recommend 106*F~ IAT)
The L33 can additionally 1000rwhp using alcohol fuel (E85) even for modest tuners capability.


economy
The 4l80e with LM7 combo through 3.56:1 and 27.4" Diameter tires will yield 21 to 23mpg highway at around 3100lbs, cruising 65-75mph which is low enough that wind resistance variations between vehicle swaps will be negligible and the estimate quite accurate for any swap in that weight extrapolation.
The L33 has slightly higher compression 10:1 and lighter -120lbs which will raise that to around 25mpg
With slightly lower gear numeric (say 3.23:1) it could even 26 or 27mpg by reducing highway cruise rpm friction
With the traditional T-56 six speed transmission some of which have 0.5:1 overdrive gear, I could see 30 or even 32mpg being quite a normal result for an L33 combo at 3000lbs.
With 3800lbs it would be more like 25 to 26mpg I guess.

gear and tire
3.54:1 and 27.4" tire is for approx 500-600rwhp (max engine rpm near 130mph range in the 1/4 mile) at 3100lbs easily using free engine LM7
Always Dial the gear to match power and tire diameter so the engine RPM is still low enough to be safe at high MPH going through the trap in 1:1
The 4l80e has overdrive and it is safe to use overdrive at WOT But this generally not recommended for peak performance , the car should stay 1:1

example
Example 5.3 4l80e turbo build in sig , I go over most of this including 4l80e build.