Getting ready to perform a LS4 swap on my 06 3.9, a salvage yard in my area has a complete drop out for $2700, is that a fair price in your opinion? the guy said it runs great but how many miles are on it is unknown. It comes from an 07 Impala.

 

IMO, that's way too high. Honestly, if the miles aren't known- I think that alone is a deal breaker unless it was dirt cheap. You could end up with a 200k+ mile powertrain that's nearly worthless other than as a core.

The thing about the LS4s is that some people selling them seem to think that since they're in the LS family that people are going to pay top dollar with everyone doing LS swaps nowadays. The bad thing is because it is FWD, not a whole lot of people buy them for swaps (outside of maybe fieros, and a few other oddball cars)- and the parts on them aren't very desirable to other LS people because the parts aren't really an upgrade to any other LS engine- and some of the parts GM used are nearly the worst of the worst LS parts (intake manifold anybody?).

I did a quick search on local craigslist for various LS4 cars- and complete running cars range from $5500 - $13k for a lower mileage one (montes, impala, GPs). I don't think it makes much sense to swap when you add $2700 + swap costs (fluids, misc stuff) + kbb on selling your current car and it comes out to the same as just buying a car that already has that engine you want in it. That would save time, hassle, and the remote possibility that you could end up with a buggy mess that never runs right. Also, you avoid the hassle of messing with insurance and wouldn't have to worry about killing resale value on the car.

Just my .02

 

Can't get an actual SS, I got a car loan on this one, but I only owe a little over $6600, I got somebody I know helping me on the swap. The cheapest ss around was an impala ss ( which I'm not interested in) for $13,798. So the swap is the route I'm taking.

 

Not trying to be rude, but why would you spend that kind of money for a swap on a car you don't own? On top of that, owing almost $7k on an 06, you're borderline upside down on the car as it is (at least if you were to trade it in you would be, if you sold private party you might have a little equity in it if the miles aren't too high).

Personal opinion, if you've got $3k cash sitting around for a swap- you're better off putting that money into paying it off so you're not continuing to pay interest on a depreciating item.


Not trying to pry too much, but do you have another vehicle that you can drive? You're going to have downtime during the swap, and like I mentioned before- there are lots of people who do swaps that end up with a buggy mess (or an immediately blown engine/trans because their 'low mileage old lady owned' powertrain was abused a lot more than they were told). I'm not saying that you will have problems, I hope you don't, but you need to be prepared to end up with a car you may not be able to drive for awhile.


I do find it tough to believe that they're so hard to find, especially if you live in the Chicago area as you have listed in your profile. Just a quick search on Chicago's craigslist brought up 4 06 monte SS posted in the last week, as low as $8200. If you were open to a GP GXP, then your options are even higher. That's not to even get into autotrader, craigslist,etc- and any other local major cities within driving distance.

I get it if you have some sort of emotional attachment to your current car, but if that's not the case, then I certainly think there are plenty of options out there if you take the time to look.

 

I actually do have some emotional attachment to this car, and I just cant justify paying 12 thousand plus getting to a 5 year car loan on another car right now. But a lot of people been telling me it would be a better idea to turbocharge it. I spoke with kevin from cartunning about a month ago, he can build a kit for this car. After browsing youtube, I found BADMONTESS turbocharged 2002 turbocharged monte, after hearing that I would probably keep the 3900 and turbo it. I got a question, whats the best exhaust set up for my car? I been hearing flowmaster super 44s are good, what do you think about an slp exhaust? sorry for the long post.

 

I was going under the assumption originally that you owned the car or were close to owning it. It actually makes decent sense that way if you could trade your car for $6-7k, stick the $3k cash you were going to spend on a swap on top of that- and that puts you easily in the ballpark to afford an LS4 car. Plus you would maintain resale value and not have to worry about insurance issues or bugs.

I agree in your position that it wouldn't be the smart thing to do. You could trade up, but all you're going to do is end up with an even bigger loan to pay off, and you could end up starting in a bad spot if they won't give you for your trade what you owe on it.

Who are these people telling you it's better to go turbo? Do they understand there is not currently a turbo kit available for a 3900? It would be cool to see a whipple supercharger on a 3900 too, but again, it's a total custom job- and that kind of work costs big money unless you can fab parts yourself. Beyond that, the aftermarket for the 60* V6 is rather small, so other than adding a custom turbo kit, you're going to keep running into a wall as far as what you can do without paying for custom parts each time.

Any competent fab shop can install a turbo on just about any engine, cartuning isn't special in that regard. You do understand what that costs though, right? The 'mass production' (if you can call it that) 3800 turbo kit from cartuning is $4500 for an intercooled setup. I would imagine the 3900 would be more because it would be a one off or low rate production, so you'd have to bear more of the R&D cost. The other problem people have in general with the big power a turbo can put out is with the transmission. 3800 people frequently run into this issue, as do even stock LS4 people- so you would have to strongly think about upgrading the transmission on top of the turbo kit price since you have virtually the same transmission in your car.

I again go back to what I said before, I would never recommend dumping that kind of money into a car you don't own. Especially when you add the cost of a turbo kit and built trans, you're going to be close to what the car is worth just in those two mods. IMO, you'd be better off taking that money and just pay the car off first and then worry about modding it later.


You do realize that's an apples to oranges comparison, right? I did a quick search on youtube, and that's a 3800 car that's heavily built. Your 3900 is a completely different engine, and other than the turbo noise, they won't sound the same at all. There are plenty of high power turbo 3800s out there, but IMO it's no different than looking at a big power turbo 350Z, or a turbo V6 mustang- completely different setups.

Part of the reason there are so many big power 3800 setups is because there are multiple bolt on turbo kits available with a range of turbo options. Plus there are tons of bolt on supporting mods (cams, heads, etc etc) for the 3800. You just don't have this kind of aftermarket support with the 3900. So in order to get to the same levels, it's going to cost you a ton more cash and time to figure things out. That's why turbo 3900s aren't anywhere near as common.

IMO asking opinions on what exhaust sounds best on the internet is useless despite how many people seem to do it. Everyone has their own opinion of what sounds good and what doesn't. Some people would be happy dumping the exhaust off the downpipe, others prefer stock exhaust, some like an exotic sound, while others like a deep rumble. None of the attributes are quantifiable by the average person without special tools, so you get mixed results. So you can't really buy exhaust based off of what someone else says is good because it may not match your taste. On top of that, how many people have really heard all of the different types of mufflers on each engine? I would imagine there are probably less than 10 members on here that have really heard a wide range of exhausts in person on a given engine. What you mostly end up with is people responding to those threads to say how great their exhaust sounds, despite only having heard a couple other types in person.

The best option is to find some local forum members with your same engine and hear their exhaust setups. If that isn't working out, the next best thing is to search youtube for the same thing. There are tons of exhaust videos on youtube to help you judge what you think sounds best to you.

I think spending $600+ on a complete catback like an SLP setup is a waste. As long as your stock piping isn't rusted out, just buy the mufflers/tips/resonators you want- and take them to an exhaust shop to weld them in place of your stock stuff. The OEM catback isn't a power restriction, so don't think you're going to gain big power spending $600-1000+ on a complete catback.

 

Good info, but as I stated in my last post, kevin from cartuning can build a turbo for this car, he told me it would run $4500. I just don't care for the 3800, I had a 2002 GT Grand Prix and it was a total dog. IMO, the 3900 is a better engine, its newer with better technology, its has way more power stock and it also has WAY better top end. Im gonna mod this car a lot, because after I pay this off im not getting another car loan for a while. I got a guy at work that can get headers made for this car. But im thinking with a good turbo set up and other bolt ons, I should see over 400 HP.

 

It sucks that theres no after market support for this engine, so everything has to be custom made, I got the sources to get headers made, now head work I don't know. Even I just did, headers, fender well intake, cat back exhaust, downpipe and a good pcm tune, that would get the 3900 over 300 HP to the crank, lets see the 3800 do that N/A.

 

I never disagreed with you, my point was just that this option has always been available to anyone, so it shouldn't be a surprise that it is an option. Any good fab shop can install a turbo on just about any engine in any car.

Have you ever driven a car with a modded L67? I don't at all propose you swap in a 3800, just that your experience was with the bottom end offering of the 3800 for the year. Not that the L67 has better top end than a 3900, but the key is the extra 40 lb ft of torque. With big cars like these, having the extra torque certainly helps make the engine feel bigger than it really is.

Technologically the 3900 is not really that much improved from the 3800. The big jump in technology comes in GM's current "high feature" V6 line that make over 300 hp out of an NA V6. If you're concerned about having a good top end, lots of NA power, and the best technology- you really should be focusing on getting one of the newer V6s- at least something with DI. Top end on the newer V6s feels much stronger than a 3900.

So you're going to do headers, or a turbo? Keep in mind, if you have headers built, you won't be able to use them with a turbo setup without heavy modification.

Why would head porting be a problem at all? Again, any competent speed shop can port heads. The only downside is there may not be a company that stocks ported heads like there is for the 3800.

Curious how you came up with the 300 hp number? Not saying it isn't possible, just wondering what you are basing that number on. A 60 hp gain from those mods seems a little optimistic.

There have been a couple of NA 3800s in the 300 crank hp ballpark. The current NA record is 247 whp. Honestly, no one bothers much with hardcore 3800 NA modding anymore because boost is so cheap and makes so much more power. When you're trying to compete with new technology, it's just hard to do that with 2 valves, low compression, and low displacement without boost.

 

Seems like good deal