Hey guys, I'm new to this forum so please bare with me. I have an 07 Monte Carlo SS that I want to begin working on, starting with the engine. In short, my goal is to get the best performance out of my LS4 engine possible with the best recommended mods for HP, acceleration, sound, etc, while also adding a turbo charger to it.

Can anyone please walk me through the process...

1. Should I get my current engine rebuild or just purchase a crate engine?

2. Should I be looking for modification add-on packages for my LS4 or should I buy upgraded parts piece by piece?

3. What is the best turbo charger kit for a LS4 engine( I've seen many and don't know where to start).

4. I am aware that this may be a pricy project but that doesn't concern me as much a getting it done right the first time.

5. Please list any and every upgrade that you can think of that will maximize the effectiveness, efficiency, longevity, and power of such a build.

6. I'm open to all constructive criticism, advice, recommended mechanics for the job( I'm located in Illinois), companies to buy parts from and whatever else you guys can come up with.

I have no intentions of this car being something that I drive crazy or even all of the time. I'm not going to run this build into the ground. I just want to for the sake of having it, to have fun in and to be able to drive fast when needed. More of a collection build than an everyday driver.
Anything will be a great help. This is a dream build of mines so im very excited to get started on it this year.

Thank you for you time family.

 

Im just curious, where at in IL are you?

Welcome btw!

 

I'm in the south Chicagoland area and much appreciated.

 

"Best horsepower" is a bit ambiguous, exactly how much wheel horsepower are you shooting for?

The sky is the limit with the LS platform, so our advice would be tailored to your goals. I imagine youre not looking to do 1000+ wheel on a front wheel drive setup.

There is no performance crate engine for the LS4 as far as I know as it's a unique block and crank. Not sure even an OEM crate engine is even offered anymore aa these cars have been out of production so long.

What is the reason for rebuilding your current engine? SBE 5.3s have been 1000+ wheel, so depending on your goals, you may not really need a built engine.

Depends on your goals, but Im also not aware of any prepackaged mod kits specific to the LS4, nor specific to turbo builds.

Where did you find all of these turbo kits at? AFAIK the Cartuning kit is the only actual bolt on for these cars. Certainly ebay has dozens of universal kits advertised, but theyd need fab work to fit.

If youre doing some kind of huge build, its probably best to get a custom kit made based around a turbo specd for your goals, but I think its pretty unlikely youre looking for that much power. The cartuning kit on its own does 500 wheel - heads/cam/intake - more meth/more boost, E85, etc can bump that number 100++ wheel depending how wild you go.

IMO the big concern with money is making sure youre considering all of your options before you dive in. Youll be $10k between just the turbo kit and transmission, and could be closing in on closer to 15 or 20 if youre adding a built engine and more mods on top.

Be sure to take a look at past big builds / issues - there's a reason so many people bail from this platform in short order after getting that high up. Dollar for dollar it tends to be much slower and less reliable than a AWD/RWD platform. I get some do it for the sentimental value of the car itself, Id just caution not going too extreme as it's a pretty slippery slope.

The most important - what is the plan with the transmission?

The stock transmission won't last behind even the stock engine, so it clearly needs upgraded if youre looking to double (or more) stock horsepower.

The trouble with the 4t65 is thr big boy parts are long since discontinued (GMR), so they're ludicrously expensive. But that just barely keeps them going on a modded 3800. Boosted + modified LS is even worse - Sam / SSV1 is doing like 800+ on a turbo LS and even with a bunch of custom one off parts, he still broke his last one in literally 3000 miles. That's not entirely uncommon either - there is no bulletproof solution that'll hold up long term.

4t80 is an option that's been fairly successful on other LS4s, but it has its own drawbacks.

 

Thank you brother for all this info. You have been a tremendous help!

After doing some further research, I've decided to just rebuild the engine that I have. Im going to upgrade the parts on my engine for some better quality ones as I do more research. I want to be able to drive the car daily if I want since I'm not much of the type to take my car to the track and race it.

One last question that i had was...
1. What would you suggest on my Ls4, Supercharger, a turbo Charger or a twin turbo? This is purely just me asking for your personal preference.

 

Im just curious, how much power are you shooting for here? Just asking as its fairly unusual to have to build/rebuild a SBE LS unless youre going for really huge power (which then leads to the problem of keeping a transmission alive behind it in the FWD applications. Ive been at 600+ wheel in my c6 with some track use for nearly a decade now with zero issues.

Some thoughts on each:

Supercharger (PD): There are zero bolt on kits available. Certainly lots of SC kits out there that physically bolt to the engine, but you'd have to fab your own belt drive and run some kind of rear inlet / sand rail type inlet (as most blower kits either put the intake up by the belt end or at least loop it around from the back to point that way for RWD applications. It would also almost certainly stick out of the hood. I think this route would be prohibitively expensive as you're probably $5-7k into a kit plus all of the custom fab work to make it work on this platform. If you had to pay a shop to do that, you could be closing on $10k all said and done.

Supercharger (CSC): These are super common on RWD setups, but they're always mounted on the crank end - which is right inside the body / chassis on FWD. You could try a jackshaft method / mount over the transmission like the 3800 have done, but I think packaging would be a real problem with how bulky the LS4 is in the tight engine bay. I think you'd have a hard time even finding a shop to attempt it. Given literally nothing would bolt up, you'd pay a ton of money for them to custom fab this from scratch.

Turbo (twin): I dont see any real benefit to this route at all. A single turbo kit is already a tight fit with how big this engine is in the bay. It's certainly not impossible to cram two in, but it would be a pretty challenging manifold / exhaust setup to build. Given it would be a one off build, the price is going to be significantly more than a single due to all the custom fab work and frankly I don't think you'd see a performance gain to match all the added $.

Turbo (single): I save this for last because frankly it's the only realistic option here. This is the only option with a pre-desgined drop in kit, and it already makes more power than the transmission can hold with the turbo it comes with. Unless you're a fabricator yourself, this is probably 50% of the cost of any of the 3 previous routes.

If youre after really big power, single turbo 5.3s have a proven track record - plenty of them north of 1k wheel horsepower on rwd setups. Certainly you'd need a bigger turbo than the CT kit comes with and lots of other work to get there, but at least from an engine perspective there are lots of examples to follow to hit whatever horsepower level you're chasing. But again, all of this is relative to how much power you're actually looking for. I'd be willing to bet that the basic CT single turbo kit alone is more than enough for what you're after. Putting down more power (on the street) and keeping a transmission alive "long term" gets exponentially harder the further above that kits power that you get.

 

I had a very detailed response and it got deleted before I could hit "send" SMH
Im short, thank you again for you detailed information and taking the time out to explain all of this to me.

I would love to shoot for 600 wheel horsepower for my 07 SS. I want to rebuild the motor because with this project it would make sense to make sure my engine has brand new parts to run optimally the first time. This car was my dream car. With all of the Hellcats, SRT's, RT's, etc on the street, I wanted my car to be a sleeper that could compete. I have no desire race these cars on the street or track but just knowing that I could keep up is satisfying enough for me. No ego in it just pride and joy.

I'll attach the link to a video of a turbocharged 06 SS racing a Hellcat on the track to give you an idea of what I am shooting for.

Also, where are you located. I wouldn't mind staying in contact with you since you clearly have a wealth of knowledge on cars...if that is OK with you.

 

https://www.google.com/url?sa=t&sour...SKIn27hEXh6GmO

Here's the link to the video of the 06 SS Turbocharged racing a Hellcat.

 

That's pretty reasonable.

Here's how I would approach it:
-Cartuning turbo kit
-Turbo cam / matching springs, on the more aggressive side. Be sure to delete dod/afm when doing this (new lifters, etc)
-Converter to match the cam
-Intake manifold (at a mininum a LS2, certainly aftermarket is good too though - none bolt on directly for FWD, they all take minor tweaks, so I'd research a bit first on the manifold you want to run / what is needed to change, some are harder than others)
-Turn up the boost. To keep it from knocking, you'll either want to go E85 if available in your area or Id upgrade the meth kit that comes with the setup to run 100% meth with either a larger nozzle or dual nozzles.
-Custom dyno tune

That'll easily get you 600 wheel.

For transmission, you'd probably be best off with a 4t80 swap from a financial perspective. A 4t65 build is going to be silly expensive trying to track down discontinued GMR parts. I also don't see a 4t65 holding that together long term.

Lastly, you'll need to seriously consider tires. Regular performance street tires are going to be a hot mess at that power level. When I first did my CSC setup on my c6 it did 585 wheel and could roast Michelin PSS for the first 3 gears (out of 6), and that's RWD with a 285. You're going to have a lot harder time with FWD and at most a 275. I ended up going with 00 treadwear drag radials (345s), but it doesn't get driven in the rain and I'm ok with ultra short tire life.

If youre planning to drive it a good bit, you probably need to look at something like a pilot sport cup 2 or maybe a little more aggressive like a r888r. That way it'll be decent in the rain still and maybe get you 10k miles out of them.

To be totally up front, youre still not going to dead hook 1st. Youd really need slicks to do that, but since you say you don't want to take it to the strip, thats not really an option. A nice DR / DOT approved race tire is about as good as you'll get.

 

Man brother, thanks again for this step by step guide to my goal. I'm going to use this as a template for my.build and adjust as needed after doing more research on this.

What do you think would be a ballpark figure price for this type of build?

One more thing....would it be reasonable to at 100-200 wheel hp to this build? If so then what would you suggest. If not then cool lol.

GOD bless brother 🙏🏾