EFIDynoTuning Forum

Im not sure if this allowed but I despite everything in efidynotuning being Ford tech related, I have not seen anything that prohibits GM or any other brand stuff here, so here's my new project start, consist of a 2003 CTS (that came with the 3.2 engine).
Why this one? Well, as a Mustang guy I do prefer coupes only BUT, the only 4 door car that I actually like its the CTS-V, but here where I live I only can dream about it price and availability wise, so I decided to start this project just to make my own version, waaaay cheaper than a real V (proving all those people that don't know a sh1t when they say "its not worth, just sell and buy a real one", lol like if I can say "ah ok, let me sell my 1k car to buy a 10k right now" when you know how to do the mechanical thing yourself it gets surprisingly cheap.

So it started in 2021 when I bought this base 2003 base CTS, with the 3.2 liter engine, the car condition overall is BAD, it cost me 1k USD.

This is how it came in the tow to my that time shop.

Now time to remove the shitty engine and transmission.

By the leaves in the windshield you can easily tell the car has sit like that for several months.

Goodbye POS engine.

Here I figured making custom mounts was extremely easy in this model. (I'll change mind later on).

This is an early picture of the engine I got for it, it cost me 600 USD, its an LM4 GEN 3 5.3 liter from a Trail Blazer.
In the picture it already has some of the V accessories but I'll list how much I paid for them later.

So far, I removed the engine and bought the LS one.

I would have swapped a coyote into it, I've always wanted to do a FORD engine into a GM product.

I'm sure that would piss off a bunch of peeps.

wwhite wrote: ↑2024 Dec 19, 10:47 I would have swapped a coyote into it, I've always wanted to do a FORD engine into a GM product.

I'm sure that would piss off a bunch of peeps.

I got your back buddy, done that before, you wouldn't believe me how crazy these swaps were, like a JK Jeep with a 5.8 GT500 Trinity engine ;)
Here's the proof, pictures from back in 2017. (Posted on 2019)

You can see more in the instagram of the shop I used to work in.
https://www.instagram.com/p/BuEt14Yh1ly ... ZGhvZzJidA

Other include a Silverado with that same engine (same anonymous owner) and a Jeep Comanche with a 5.4 lightning engine.

After removing the engine I took the car to a yard where it sat until I got most of the parts needed to continue with the swap.


In the process I bought the engine shown in the previous post, used LM4 5.3 from a Trail Blazer
-Used CTS V accessory drive (PS Pump with bracket, alternator bracket, water pump and ac compressor with bracket.)
-New alternator
-Used LS6 harmonic balancer
-Chinese long tube headers
-Used CTS V2 (2009+) oil pan, it is the same as the V1 oil pan with the exception of having extra bolt holes for a cooler.
-Used engine mount brackets.
-New regular CTS engine mounts (pretty similar to the V mounts with the exception of lacking extra location pins that let you easily align the mount. (not really needed)
-Paid 200$ to fix a 4L70E transmission core I had from a customer Trail Blazer SS (not the same where the engine came).
-A like new LS6 intake manifold with injectors.
-Used LS6 throttle body.

Important note here, I took me two years to buy all those parts... That doesn't make sense right? Well for me yes it does, this project car was just running on the background where my main project is my 95 GT and the CTS was stored where it doesn't bother me in any way, so when there was chance I purchased a part at a time, being the manifold and the engine itself the most expensive parts.

By December 18th 2024 was time to move the car to my new shop, unfortunately...

The sun ate the paint! I gotta say it looks bad af, but I don't care, I want to get it running soon.

Here you can see some of the parts I purchased and the time the engine was going inside its forever home.


Installing the engine was extremely easy! One of the easiest ever Ive done.

I have to add something more, I purchased more than necessary stuff, V accessories weren't even needed, I could just bought a 2010 Camaro SS water pump and some cheap ass Chinese accesories brackets and would let me mount everything with the original truck spacing saving me hundreds of bucks, V engine brackets weren't needed as well, I could just make the brackets by myself but I wanted to do it that way, they were available and I had the cash in hand so it isn't a big deal btw.

Out of curiosity, why the 5.3 vs a 6.0 or 6.2?

Cougar281 wrote: ↑2024 Dec 20, 18:37 Out of curiosity, why the 5.3 vs a 6.0 or 6.2?

The main reason is because aluminum blocks have a provision for an extra bolt in the engine block needed for the OEM CTS-V engine bracket, was it really needed? I think I could figured something out but it was easier this way I wouldn't raise or lower the engine from the stock position.
Other reasons are:
-Recently the LM4 held the record of the fastest stock block ls engine
-Aluminium is lighter (As a SBF guy I know one of the main benefits of aluminium head is the weight)
-I always wanted an aluminum gen III sbc
-Price, In my city swaps are common and yunkyard guys know it, so 6.0 are more expensive
-With the bolts'on I already have, I'll have more power than a stock 6.0
-I race my mustang, so I don't really care about the power of this car.

In your thread here, how did you get your pictures to show up full size?
Interesting swap!

the ct5V is about the only new vehicle id have any interest in but at 100G its not even a consideration

same for a new GT at 50k I cant even consider it.

If Trump cant fix the economy next year Id assume more and more engine swaps will become commonplace.

ATPCR wrote: ↑2024 Dec 21, 21:26 In your thread here, how did you get your pictures to show up full size?
Interesting swap!

Im using imgBB (imgbb.com) as host for my pictures, I'm positive they'll last years, but if someone knows a longer/permanent lasting host let me know :)

decipha wrote: ↑2024 Dec 22, 11:45 the ct5V is about the only new vehicle id have any interest in but at 100G its not even a consideration

same for a new GT at 50k I cant even consider it.

If Trump cant fix the economy next year Id assume more and more engine swaps will become commonplace.

I can only dream about it, personally I do prefer it over the charger hellcat