Are the vortec Engines classified under the LS Family?

Whats the differences of the motor variations named LM7/L59/LM4/L33 ?

How much does a 5.3 differ from a 5.7 LS1 really?

 

I would start with http://en.wikipedia.org/wiki/GM_Vortec_engine http://en.wikipedia.org/wiki/General_Motors_LS_engine

 

I have done that, it basically says the displacement is different. i checked many sources and it seems the block can be taken apart and rebuilt with many LS parts. However most sources tell me to "check with LS1 Tech, those guys know everything." I was hoping for more information than a Wikipedia page.

 

The 5.3 is the same family as the ls1. the # you have are different configurations of the 5.3. The L33 is aluminum like the Ls1. The Wikipedia tells you the differences.

 

What specifically are you looking for...???

 

I will be picking up a running driving 5.3l Silverado that was bought back from insurance after being "totaled" I am interested in pulling the motor/trans from it and put into a running driving 72 Chevy truck that currently has 355/TH400.

This 5.3 has 300k miles and i know i should freshen it up before i install so i can get the reliability. What i dont know is what upgrades to give it while i have it open anyway.

I see allover the internet this type of swap being done with LS motors but never see anyone doing vortec swaps. Aside from that i find the vortec has 2 different versions apparently the late 1990's were more of a small block 350 with vortec heads but in the 2000's it became a new design that more resembles the lS1.

Im wondering how similar is this? Wikipedia just says the bores are different so it has a smaller displacement. this gives a reader the thought is it a LS1 design that was under bored and de tuned? can i change those wikipedia dimensions and have an LS1? Wikipedia info indicates most likely the truck i buy will have a LM7 (garden variety), and cross fingers its an L33 (however they were reserved for 4x4)

Since im buying the complete truck, bumper to bumper. ill have all the bolts, computers, wiring, etc.. My thought was part out everything i dont need to finance the parts i missing.

Should i sell off the 5.3 also and just buy a LS1, if i did that. could i reuse any of the 5.3 wires or computers or would i have to go buy those too?

I have many questions and dont even have the silverado yet. I really thought id get information from people that knew these motors versus getting a link to a page that is so vague.

 

Ok well to start off with VORTEC is just a name chevy has given to its line of truck motors. The older style trucks 98-down had vortec engines but were based on the old SBC architecture. Starting in 99 they got the "new" vortec engines which are basically iron block ls style motors. Meaning everything interchanges, heads, intakes valve covers, coils etc with the ls1/ls6.

The different designations you see for the 5.3 either dictate the block material or what heads/other small changes they may have had. Bottom line is if this 5.3 is out of a newer pickup everything will be just like an ls1 swap. The bolt holes, and all external mounting and wiring will be just like an ls motor.

Like you said the 5.3 is basically a debored ls1, meaning if you punch the block out to 3.90 and use the right pistons you will indeed have a ls1 displacement but with 5.3 heads and an iron block in most cases. Now then you can add a 4.00" crank to that same block and get a 383 just like an ls1 can achieve. The ls family is unique in the sense that all external accessories will bolt up and ALMOST all heads interchange until you get into the large 6.2 liter bore rectangle heads.

 

This is the perfect way to get into the reasonably priced "LS swap" world...This is how I start all my swaps.


You will be amazed at how this thing will look when you get it apart. The last 2003 Suburban I bought had 397,000 miles on the clock...when I pulled that 5.3 apart I couldn't believe how little wear it had on it. I just ground the valves, changed the stock springs to the "blue" GM springs, bought a used LS6/ZO6 cam, and ran it...didn't touch the bottom end.


You'll be suprised at what you will be able to sell to recoup your original purchase.

Don't sell the 5.3, use it...you can always upgrade to 5.7 later...but you won't want to.

 

Once this starts i plan to start a build thread and document everything, For my own information and for others to learn from my experience/mistakes along the way. This will be the first time I get deep hands on with a motor. all hand tools sockets and wrenches, i dont own any air powered tool except a cordless screwdriver.

Side question
Can the LM7 also be built to LS6 specs just as easy as LS1. The only google info i find with these key words is someone putting an LS6 cam into an LM7 but they get told its better to get a custom grind.

 

What do you think i should have for rear end gears? the 72 is a C20 3/4 ton 8 lug and currently has something like 4.56 (unconfirmed).
My ultimate goal is autocross style, weekend cruising, parking lot drifting. Low stance, great handling and brakes, power on tap anytime. However i have no real need for ever going over 90 mph as it will never get on a drag race track .

 

Don't bother trying to build one GM engine in to another. Sure you could put LS6 heads/cam/intake on the 5.3l but why not actually come up with an intelligent plan instead. The truck intake isn't pretty but it is very nearly as good as the LS6 and I think the 08+ truck intake is even better than the LS6, the truck engines from then also use the same head casting as the LS6. Guess what I am saying is if you have some hardon for an LS6 but are buying a 5.3l then just buy a newer one that has the same heads and a better intake already.


Tranny and tire size? Discussion of gearing without those details is pointless.

 

Transmission: Whatever automatic is coming from the donor 00 silverado. Tires: figure something just bigger than standard silverado size maybe like 285 or 275/75 or70/r16 I don't know the conversion but I'm guessing 28-30 inch diameter

 

its a 325 as it is. if I have to have it bored out after I open it I want a bore size that's well known to be worth it. The only #s I'm aware of are 346 or 383. from what I'm reading Apparently the 4.8l flat top pistons are good keep my heads or go trick flow a 220 .5 112 cam may be nice . manifolds won't fit. Frame may not allow AC.

 

If it has flat top pistons it's a 4.8 and not the 5.3.

 

So I think I pick up the Silverado this week. Parts sourcing should begin

 

you can actually bore the iron 5.3 block out to the ls1 bore. ls1 engine are over priced for what they are.

the early 5.3 heads are very very similar to the ls1 heads as well. so they just need a spring change and they're good for a decent cam.

 

So its changed a little, i have a 4.8 that runs and a 5.3 with a knock.. where to go from here?

 

I bought the dirty dingo mounts