I own a 2002 Monte Carlo ls and recently after owning and driving it for a year wanted to get into the modding world. I don’t really know where to start or where to go I’ve been on ebay and talking with my friend and have had a few ideas. I was thinking about adding an air intake system, coil overs, and down piping it. I’m very inexperienced in the auto world and any suggestions on this matter would really help, thank you.

 

Not trying to be rude, but just trying to be up front. These NA v6s of this era don't respond well to mods. The 3400 being even tougher than the 3800 as there is a far smaller aftermarket for it.

I'd bet an intake + down pipe would be low single digit hp gains (likely within dyno error and likely impossible to feel). Id just hate to see you spending a bunch of time and money on it for no real change.

Not trying to dissuade you from modding the car in general, I'd just suggest against doing minor engine mods like that. Unless you're thinking about getting into bigger mods like a cam swap or boost, I'd probably just slap some mufflers on it so it sounds more powerful and leave it at that.

 

Thank you for replying but I was planning on doing a cam swap and I was told I need to down pipe it too which was the reason I said that. All i could find though was a 2nd stage cam and have been looking for a 3rd stage to no luck, but if I don’t wanna accidentally blow the engine or overheat it. Would it be smarter to swap the engine or is there other bigger mods I could do to the engine. I would also like to know at what point would I probably have to swap the transmission.

 

The main issue with w body downpipes in general is the U bend at the back of the pipe. Some cars have a U shaped dip to protect the rear O2 that also also constricts the ID of the pipe on top of adding a bunch of useless bends. If you've got a U bend, any exhaust shop could chop it out and replace it with straight pipe (with the rear O2 moved to the side) for far cheaper than a full downpipe replacement.

It certianly isn't "required" for any mods, but is a common starter mod on these cars.


I will admit up front that I'm not overly familiar with the 3400s. My monte came with a 3100 (basically the same engine) and I swapped it out due to lack of aftermarket.

Before you commit to doing a NA build, I'd poke around to see if you can get some actual dyno #s from people who have done those mods. Reason I say that is the larger 3800 has virtually no NA modding following anymore because the power output from mods like this is so miserable in terms of $/hp and total hp made.

For example - the 3800 stock cam NA power record (with ported heads, rockers, numerous other mods) on the 3800 is 193 wheel horsepower. The guy behind him even shaved the heads after porting for nearly 10:1 compression and still came up with only 190 wheel. Neither of those cars even make what a stock supercharged 3800 does despite literally thousands invested.

Moving over to the cam swapped / anything goes NA record list (ignoring a one off shop sponsored drag car), there is one guy at 233, another at 222, and literally everyone else ended up at 190-210 wheel. So the typical cammed NA 3800 build makes just a handful more hp than a bone stock supercharged 3800 - despite the huge amount of work and cost. Even the two record setters ultimately regretted wasting time on it and went boosted later.

I don't follow 3400 builds, but Id strongly suspect their NA setups aren't doing much better than the 3800s are - especially given they're starting 20 hp down out of the gate.

You could always have the place that makes the 2 stage cam custom grind you whatever cam you want. If they're doing cam grinds, they've got the data to make cam blanks and can have whatever profile ground into that that you want.

That was the path I took. The supercharged 3800 is nearly a direct bolt in/ plug in and is dirt cheap as there was a huge quanity made. Stock they made 240/260 crank hp, but mods with the factory blower have put out 400+ wheel horsepower or with a turbo conversion have done 600+ wheel. Thats all on a stock bottom end (block/pistons/crank/rods).

I bought a complete (totalled) grand prix for $1500 when I did my 3800/4t65HD swap - so that's why I hate to see people spending hundreds/thousands on mods that are adding single digits amount of horsepower - especially if they have goals for much higher.

The real way to add big power to these is boost. I don't know where the limits are for 3400s, but adding a turbo can practically double the stock horsepower with supporting mods (cooling / octane / etc). Even the best NA builds can't come close on power production (not to mention the turbo doesn't negatively impact drivability like a big NA build does.

I don't think there are any bolt on kits for the 3400s though like there are for 3800s. It can certainly be done as a custom one off though following the same piping scheme as the 3800 kits do (which fit into thr same body).

There's not a good answer to that as a lot of it boils down to use. A car hitting the drag strip every weekend with drag radials/ slicks is going to blow at a far lower power level than someone who spends 99% of the time cruising around and only makes a full throttle pull every once in awhile.

Thats complicated by the fact that these cars are older / higher mileage now. Its not impossible that your transmision falls apart tomorrow without you having done a single mod. There is a fairly high % of these transmissions that don't make it to 200k even behind a bone stock car.



We could help suggest a path forward if you let us know your budget + how much hp youre shooting for.

 

My monte sits at 91k miles at the moment. I do plan to put at least 10,000$ into it and I’m trying to achieve 300 whp. Me and my friend do all our mechanical work at home and he’s more of like my mentor. He has an eclipse and has added a 3 stage cam to it a long with other modifications. He’s been in the world of cars since he was a kid and I more or less just got into it and just started learning all about engines. Honestly I haven’t been baby the car like I was told I was street racing and hitting sharp turn going around 80 but recently started using it as just a daily since march. There is practically no problem I need to replace the EGR valve and apparently it’s getting too cool and I either need a new sensor or to replace the thermostat I think I don’t remember. The reason I wanted the air intake was to make sure my engine got cooler to avoid overheating damage. I greatly appreciate all the help you’ve given me and I’ve even learned more about my engine from it. I don’t mind swapping to a 3800 supercharger I actually have been looking into that ever since my friend showed concern over blowing my engine w a turbo. The main point of this is I don’t want people to look down on my car anymore, it’s been called a sh*t box even though the last owner babied it and it’s practically in new condition. Thank you for your time though it means a lot.
​​​​​​​

 

Before you spend your first penny, I'd seriously think about your path forward. Not at all trying to knock these cars, but $10k can get you a v8 RWD platform vehicle (on top of your monte) that can be infinitely faster + more reliable. You can keep you monte as a reliable stock driver and mod the new RWD car instead. I know covid has driven prices up, but even today thatll almost get you a c5 corvette. Itll certainly get you a v8 fbody, or maybe even a higher mileage 04 gto.

If you want to stick with the Monte, I get it- I did the same thing (but ultimately ended up adding rwd toys as well, lol). I just want to point that out before you jump in and regret it.

That number forces you to the power adder route. I don't know what the 3400 NA records look like, but even the all out 3800 NA builds are over 50 wheel shy of that. I suspect the NA 3400 builds aren't doing much better. That is easy to achieve with a power adder though.

The air intake has virtually zero impact on coolant / engine temperatures (and frankly even the stock one is sucking air from a pretty cool source so you really aren't going to see IATs substantially lower than stock with an aftermarket intake). The vast majority of cooling is done by the cooling system- radiator / water pump / fan. To cool the car more, you need a bigger heat exchanger (radiator) which is available through ZZP if needed. Its not particularly common to need to upgrade it though as the engine mods really only impact the car at heavy / full throttle. Even if it makes 300 whp at wide open, its still going to make the same power as it did before cruising around town at part throttle (because you're limiting power with the throttle), so the heat output by the engine will be similar to stock levels everywhere except the short bursts of wide open.

Generally the people that need an upgrade are those with sustained heavy throttle - autocross, road course, big power cars doing 1/2 mile events, etc. Thats when you start to see the extra heat from the added power as you're actually using it in a sustained manner and really generating some engine heat.

I'd start seriously reading up on a L67 swap then. Its easily in your budget (including the HD transmission), and is the easiest way to 300 whp besides nitrous. You'll still need to pick up an extra 100ish wheel horsepower to meet your goal - but there are several good paths to do that on the stock supercharger with a smaller pulley.

I know the 60 degree guys hate to hear people say that, but given there isn't a bolt on power adder for the 3100/3400, it makes boosting the current engine a lot more of a chore. The L67 bolts in and is 99% plug in with a drop in NA 3800 engine harness (zzp sells an adapter harness to convert to the supercharged style for like $30 - its just 2 wires, one that isn't really even needed).


Another alternative is a NA 3800 swap (L36). They'll be dirt cheap at the junkyard as there are so many out there that the higher mileage ones often get tossed as unsellable. The flip side is youll need to spend a few grand on a turbo kit. Itll get you to 300 wheel as easily as a modded L67 will, just a different way of going about it. You'd also be done with a single mod (a complete turbo kit - IC, injectors, tune, etc) vs having to do a handful of mods to get an L67 there.
​​​​​​​

 

Been poking around to try and educate myself on what the 60* engines are making with NA builds. Stumbled across this one below (which happens to be a 6th gen monte):

https://www.60degreev6.com/vb5/forum...e-build-thread

Forged pistons with higher compression, aftermarket rods, ported heads, drag strip cam, custom one off long tube headers, custom dyno tune, and several other mods. Made 217 whp and the engine ate itself after just a few years...

Not saying it died from the power, but even if it lived forever- The power alone is really poor considering it would probably be $5-10k for someone to replicate that setup having a shop do the build.

 

Some things I will put out there:
1. - The 3400 is way bigger in the N-Body (Grand Am/Alero/Malibu) community. Even with the Beretta community. Many who work to build up some big power build a 3400/3500 hybrid and then usually slap a turbo on it.
2. - I still drive a 3400 Grand Am as a daily. I never got into "building" up a 3400, but I did get into some cheap mods. Here is a thread I did on that topic:
https://montecarloforum.com/forum/fw...p-power-46071/

And I did not read everything here, but Bumpin has a point, if $10k is your budget, really weigh out what you are trying to accomplish and is it worth it on this platform.