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LS4 performance

78538 Views 50 Replies 19 Participants Last post by  Whoaweezy
Anything you would like to know about the LS4 motor found in the 06+ SS models can be found here on this site. So if your looking for the engine performance aspect of the car you may want to look around here.

LS1/LS6 Intake swap: LS1/LS6 intake swap Sticky!!! - LS1TECH

Suspension Upgrades with options: Impala SS Bilstein BMR ZZ GXP Suspension Upgrades Done! - LS1TECH

Shift Kit Install: Shift kit install, very detailed (56K go watch a movie) - LS1TECH

Info on the LS4 and the transmission it carries: Information on the LS4, DOD, and the 4T65E-HD - LS1TECH

LS1 install guides: Information on LS1 installs

how to build a TRUE CAI: 2008 Impala SS LS4 True Cold Air / Ram Air Induction System - LS1TECH

Headers for the 5.3: HEADERS 5.3L LS4 FRONT WHEEL DRIVE HEADER 2005-2009 IMPALA SS/ MONTE CARLO/ GRAND PRIX GXP/ LA CROSS at Doug Thorley Headers

Magnaflow Complete cat back exhaust:

Cartuning Turbo kit: Cartuning Performance
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Ok, before this thread gets totally derailed with all the talk of heavily modifying a 3.5, can we please keep this an LS4 Performance-specific thread please??? Not trying to steal your thunder or push you out Whoaweezy, but try and keep your specific stuff to its related thread(s), start a new thread specific to your build for others to follow, or section of the forum. This IS the section for the 5.3L LS4 bro...

And now to get back onto the topic of LS4 performance: a few days after Christmas, someone on the LS4Nation page on Facebook had made a rather shocking discovery regarding an LS4 powered car - an '05 Pontiac Grand Prix GXP that was for sale on Craigslist in the Battle Creek area of Michigan.

Now for the last year or so, a lot of the LS4 guys have been wondering about doing a supercharger on the LS4, with no real answers or possible outcomes. Not the right kind of system, no real room to fit, etc., etc... Now what this one person discovered about this particular GP GXP, was exactly that... This car had a supercharger on it!!! It is an actual GM unit, but it was custom made for the LS4 application using 2 main components from 2 different GM superchargers, along with a custom snout for the throttle body and a new drive pulley to be used in the rear for the LS4. But it has been done, and I wanted to share this with you guys.

Now be forewarned, this is NOT a readily available unit for these cars, it was custom made, and it is more than likely going to cost as much as - if not MORE than a turbo kit for the LS4... But for those of you who are interested in the details, follow this thread, or the thread I am going to make specifically for this topic. This post in this thread will be for the general thoughts on it. More specific thiughts, comments and whatnot should be posted in the specific thread for it...

So ladies and gentlemen, a present to you, a little taste of what a supercharged LS4 is... Anyone care to guess what the 2 main parts to the supercharger itself are, or where they came from???


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Your cool thanks for your help and input

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Your cool thanks for your help and input

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:WTF: Was that directed at me bro??? If so, no need to be a douche about it. I am not trying to be one to or towards you, or your idea or what you want to do for your build... I honestly think that what you are trying to do for your drive train is a great idea. Being a pioneer for something major for that motor is great, and I think you will get a good following for it if it all works out. And just so you know, I am actually following your thread and progress to see how it all comes out.

However, you are dealing with the 3.5L V6. It is nowhere near the same set-up, internals or anything to the LS4. I see what you are doing, and trying to base your ideas off how the turbo kit on the LS4 would apply to the 3.5L, but asking specific details about your internals and stuff should be done in the main 8th Gen Engine Performance section, or start your own thread for it. Asking about which internals and stuff you will need for your 3.5 in the section for the 5.3L LS4 guys is derailing the thread for the rest of those interested in the specifics for the LS4.

And further more, I personally don't know anything about the 3.5L, as it is not my current platform of engine. If I DID know, then I would reply directly to your thread about your build, and tell you the answers in which you seek.

Again, I am NOT trying to be an asshole about the whole thing, just merely asking you to please keep your specific questions regarding your motor out of the LS4 thread. I have NO problem with you, or that you are trying to get ideas from how the LS4 turbo system is run and piped for you to help get your build off the ground. Like I said earlier, it is awesome that you are pioneering something new for your platform. But I personally don't know the 3.5L like I do the 5.3L. So therefore, all the speak of the 3.5L is basically Greek to me.
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No i wasn't being rude lol i was saying thank you for your help u made me do alot of thinking for this project is all i was saying

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Tbh i dont even know how got to the ls4 thread bro i thought we was still on mine haha sorry

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Looks like part of that supercharger is off the LS9...not cheap
No i wasn't being rude lol i was saying thank you for your help u made me do alot of thinking for this project is all i was saying

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Oh, okay. And yes, undertaking a massive task like this would do that to a guy!

Another thought to consider in how your piping and whatnot for your turbo would sit in yours: check out pics of how everything sits on the LS4 when it's in the car, under the hood. Then compare under your actual hood to see where things would need to sit, what you would need to modify, etc., etc...

Also, see if you can get a spare set of exhaust manifolds from your car - another 3.5L, to be able to start any kind of fabrication work for the flange of the turbo on a crossover pipe, new downpipe shape and position and how it would need to run and connect with the rest of your exhaust... getting the ideas and basics off the LS4's system is a good way to get a basic idea for yours. But I would actually want to look more at my own set-up for where and how things would need to be run, where things would need to sit and so on.

Or if you can pick up a spare motor from a wrecked car for fairly cheap, even better way to get a lot of your custom fab work done... this way with a spare motor out of the car and in the open, it will give you the room to move around it and have more access to parts to remove, modify, and bolt back on to see if your measurements and fitment is correct or not. Not only that, but would also be a prime time to rebuild the new (spare) motor to the new internals and stuff you may need or will want... nothing like having a freshly redone engine to.have all the new stuff bolted to and ready to drop in when the time is right...

Doing this with the 3.5 specifically - especially when it's in the car, will give you a lot more specifics for your application than trying to base it all off another platform. It may be close and similar in many ways, areas and aspects, but different just because of your motor and how it all.sits under your hood.

Just some thoughts and ideas from an outside angle... Again, good luck with your build man. Keeping an eye out and wishing you luck on it! And it's all good man. No stress!!!
:eek:k3: :beer:
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Yes sir Jeff, you are partially correct. That IS the upper half (intercooler) from the LS9 supercharger. But the bottom half is NOT from the LS9... the blower itself is a 1.9L roots style blower, that is the hint/clue. The LS9 is a believe a 2.3L, so it is not the same blower from the LS9...

And the guy that did it, said that he whipped it together from stuff he had "laying around the shop"... Just makes you think and wonder about what kinds of cars he's really working on if he has stuff like that "laying around the shop"...
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The bottom looks like a 1230 supercharger but culd be wrong but I seen zl1 lids for cheap and get a good amount of performance out of them
Thanks bro

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