ricche

Just got my recent 8th gen maxima not too long ago. Really love the aesthetics of this car from the exterior design to the interior design. In my opinion it provides a lot more comfort than the q50. But someone recently told me modding this car would be the issue cuz of the cvt. Aside from intake and exhaust would it be at all possible to bring this car to 400whp? or at close to it? I've seen some Subaru WRX's with CVTs that have been modded on YouTube to get more horsepower. Couldn't one apply the same methods to mod the 8th gen maxima CVT and engine?

dmc79

Not likely, mainly because the WRX is turbocharged. A simple tune will add significant power by itself, and bolt ons will allow that tune to be even more aggressive. 400 hp is certainly possible, although I wouldn't do it on a CVT equipped car. If you do bolt ons for the Maxima, about all you will get is a more aggressive sound and very little extra power. Attempting to add forced induction will be an exercise in frustration and extreme expense. Unfortunately, if you want a big 400 hp sedan, you either need to buy something like a 2.0T Accord and mod it, or a Charger Hemi.

ricche

what if i change the cvt into a 6 speed auto like they did in nisformance?

Fishlet

anythings possible if you got the cash and the time. Assuming your not looking to spend 10 grand on new parts, neither the existing power train, nor the front wheels going to handle that much power.

I always scratch my head wondering why folks want that much power. It'll just make your daily commutes stuck in traffic that much more unbearable. If you really wanted a racer, there are plenty of other vehicles designed for that purpose.

ricche

I mean personally for me its for the fun of the drive and putting some work into something I really care about. I'm a huge maxima fan and the fact that Nissan claims this to be a 4DSC when you can't add or mod its performance kind of irks me. Especially when I see things like a Nismo Juke and now the Juke also gets a GTR Nismo engine as well? And getting a new car would be a good idea except I really love the Maxima body, its BEAUTIFUL! The interior as well, it beats the interior of the GTR and most current infinitis hands down in my opinion. Thats another reason why I would love for the opportunity to make this maxima live upto it's 4DSC claim. It's also under 10k miles, so putting some extra money into modding it somehow would still be a tons cheaper than buying a brand new car right? I don't think it would cost 10k just to make it reach a higher HP right? At least thats how I look at it. As for the daily driver, if gas during daily commutes becomes an issue I can just switch to my 2011 Honda Pilot as my daily driver or get one of those pedal commander things that thankfully doesn't void any warranty.

Fishlet

Glad you appreciate the fine points of the Max as well, they really knocked it out of the park with the design, and the performance is above average for a 4 door car of its size. Nissan really did themselves a disservice to brand it as a "sports car".... it's not. And the reason is not because of horsepower. The front wheel drive and CVT make for driving dynamics that the average enthusiast would not call sporty. Personally I really like the CVT, especially the smooth uninterrupted flow of power when hitting the on-ramps, but it's a very "computer controlled" experience that may not always react the way you expect it to when doing "spirited driving"

But if you live in a area where you can have a little fun with your car, than perhaps you can get a little more performance for under 10k. I just think asking for 400hp is a bit of a stretch. Here are a few things you can do

As you mentioned, a product like Pedal Commander may improve the responsiveness some. Not sure if anyone has tried it with the 8th gen but there have been some good reviews for older models.

If the air in your city is relatively clean, and your not doing dirt roads, you can try a K&N air filter. They don't filter as effectively but they do allow for better airflow. The horsepower claims they make are probably exaggerated, but in my experience it does help responsiveness a bit

There are no electronic tuners yet, or none that have been confirmed to work. I imagine if one does come out, it will work by disabling the d-step logic and allowing the CVT to do what it does best, stay in the powerband.

Many folks on this forum have replaced their exhaust pipes, but I think this is more for aesthetic reasons and better sound. If the pipes add weight to the car than it's a bit counter productive . Which leads to the final point... you can get better performance by putting your car on a diet. Reducing weight is just as important as adding horsepower, which is why you have zero chance of beating a motorcycle when the light turns green

It's difficult to trim much weight from a car, but here's a few ideas.

1. some cars have carbon fiber replacement hoods and panels. It not sure about the Max

2. Get 17" wheels (yes really). Smaller and lighter wheels will help 0-60 times , not top speed.. but how often will you be doing 130 anyway?

3.The obvious, don't carry much stuff in the trunk if you don't need to. If you got a heavy girlfriend (or boyfriend) , leave her home

ricche

yeahhh i decided to leave my spare in the garage since it adds like an extra 30 pounds or so. someone actually made another post about a v-charge super charger which seemed kinda cool. i'm gonna look into that.

Roddy13

400WHP??? You realize WHP stands for Wheel Horsepower Right? ie after drivetrain losses.... As a heads up our 300hp Maxima's after the stand 15-20% Drivetrain losses might make 240-255WHP ....

Now how much potential is there for gains with aftermarket parts. Next to none! The intakes out there for our cars are JUNK short ram warm air intakes... there are a couple axle back offerings (no gains here) and one company left who makes a $600 Y-pipe .... No one can tune our cars either. ECU's are locked and no one has cracked them.

OP if you are lucky and throw an intake on with Y-pipe and Cat back you will gain maybe 5-6 whp. (for $1400)

So 245-260whp is the best our cars will do.

Now in saying this... I love these cars, but they aint no race car... quick as heck! But i'd recommend a K&N drop in filer, 3rd cat delete and call it a day until someone can tune these ECU's

BlueSR

Few things that prevent 8th gen Maxima and that 400whp dream:
1. CVT: the CVT8 in the Maxima designed to handle up to 280 lb ft of torque. Stock 8th gen Maxima is rated at 261 lb ft of torque. You don't have much head room left for power from turbo or supercharger.
2. Currently there is no tune for the 8th gen Maxima. No tune mean you can't alter fuel and timing for big power gain.
3. Currently no turbo or supercharger kit for 8th gen Maxima. If the CVT can't handle big power, there is no point for vendors to developed turbo or supercharger kit.

ricche

Thanks for the insight guys! Really appreciate it. I don't know much about cars but I'm trying to learn more and more as I go. The VCharge Supercharger thing one of the other guys mentioned on here kinda looks promising. What do you guys think about that?

RickSmith

Interesting article from How Stuff Works:

"Superchargers do, however, cost a little of the power they produce. Unlike a turbocharger, which runs off the engine's exhaust (waste) and therefore doesn't drink up any additional power, a supercharger is driven by a belt or a chain connected to the engine -- and that does drain some power, just as all other belt-driven accessories do (like air conditioning, for example). This is one of the reasons a supercharger can't deliver a promised and consistent power output -- the supercharger itself affects the way a car runs. In some cases, it can sap up to 20 percent of the engine's power before it contributes its own boost to the equation."

https://auto.howstuffworks.com/how-m...harger-add.htm

RickSmith

"If I remember correctly the rule of thumb is that it takes approximately 30% of the power out put to drive a Roots type blower. Higher boost and horsepower means higher losses, but the percentage stays pretty constant. This is a very elementary number based on typical street engine inefficiencies and gasoline.

So in other words if you are making 400 HP at the crank with a blower it is taking about 120 HP to make that power ~ in other words if you could make the blower 100% efficient, you would be making 520 HP.

In a Top Fuel car, they figure somewhere between 900-1100 HP is being eaten up by the Blower at the 50-70 lbs of boost that they run. Remember also that Screw Blowers are more efficient than Roots blowers and Nitro changes everything."

https://www.jalopyjournal.com/forum/...blower.775299/

RickSmith

Hot Rod Magazine actually did a comparison test of a roots-type blower, a centrifugal blower, and a turbocharger all set to produce the same boost (9 psi IIRC). The turbo made more mid and upper-end power and in fact, the only place where the roots-type blower made more power was at the very low end of the spectrum.

Here is one article.
http://www.hotrod.com/techarticles/t...son/index.html

RickSmith

It takes power to pump (compress) a large volume of air (700+cfm). The supercharger's power is derived directly from the crank shaft, where as a turbo's power comes from energy contained in the exhaust gasses. On a typical 8 psi supercharger, the power used can be in the neighborhood of 40-60hp! On a 1500hp engine, the power used by the supercharger can be as much as 300hp! This would leave only 1200hp to accelerate the car.

A turbo is not entirely 'free' horsepower as some additional back pressure is created by the turbine, but a turbo derives a very large portion of its energy from heat. This is shown by the fact that exhaust gas temperature can drop by as much as 300 degrees Fahrenheit as it leaves the turbine housing. In essence the power 'robbed' by the extra back pressure is very small.

So what does this all mean? Basically an 8 psi turbo kit will produce more peak power due to the fact that a supercharger is using a fairly large amount of power just to get it spinning. What is more important for a street car is 'power under the curve' meaning the average horsepower produced. This is where the turbo really shines since you can have full boost at as little as 2500 rpm! This will make the turbo car feel like it has 50% more cubic inches (or more). The difference in torque at low rpm's can be as much as 100 lb ft in favor of the turbo due to the additional available boost.

http://tomak3.tripod.com/page10.html

RickSmith

In all-out racing applications, turbochargers are the undisputed power champs. The rules of thermodynamics dictate this. It takes a considerable amount of power to compress a large amount of air. To generate enough airflow to produce 1,000 hp from your EVO would require sacrificing about 80-120 whp just to turn the compressor.

A turbocharger recovers most of this power as waste heat that would otherwise go out the tailpipe. A supercharger takes this power from the crankshaft, subtracting its power requirements from the total. This is called a parasitic loss and is why, especially with high-powered applications, the turbo always wins.

http://www.superstreetonline.com/how...rcharger-tech/

Fishlet

Thanks RickSmith for the interesting comparison between a turbo and a supercharger.

So all this makes me wonder if something similar and better can be accomplished by doing the following.

1. Pair the Maxima with a traditional turbo
2. Using a rpm regulated gate, bypass an increasing amount of the compressed air away from the engine, up to 100% at full throttle.
3. The gate to rpm ratio doesn't have to be perfectly linear

I think this would in the following way

As the engine speeds up, the exhaust pressure feeding the turbine also increases. So like a traditional turbo, there isn't a whole lot of boost at low rpm. As the rpm increases the pressure from the turbine increases, producing more air flow into the engine and more power. As the rpm starts to increase past the midway mark, a "gate" gradually opens, diverting an increasing amount of boost pressure away from the engine out to the exhaust. Therefore the boost is discharged, keeping the engine from generating too much power at high rpm (and damaging the CVT)

This boost curve causes the engine to produce additional power in the midrange.

Now I'm going to shoot down my own theory and explain why this might still not work on the Max. I presume the CVT's "gear" selection is also based on the rpm. Having more power at 4000rpm (for example), the transmission could select a higher ratio...and therefore produce faster acceleration. Since those ratios are preprogrammed based on the expected power output of the stock engine, I imagine those more favorable ratios would still not be selected at lower Rpms. You may be able to work around this to some extent with the paddle shifters.

BlueSR

Fishlet, I think you are trying to complicate things. If the goal is to increase low end and midrange, you can do any of these.
1. Use a tiny turbo like most OEM do. Torque curve will be flat from ~1500rpm to ~4000rpm then taper off.
2. Use a roots type supercharger.
3. Use a centrifugal supercharger with smaller pulley to create more boost at low end and midrange but install a restrictor plate on the blower inlet so boost will not keep rising with high rpm.

Fishlet

I wouldn't say I'm trying to complicate things. But for as many people want to tune up their cars in this forum, there has been very little mention of existing options that fit the bill. I assume most people equate power with better acceleration. Better top speed is good too, but I don't think most are going to the track. If the goal is to go well over 100 on the main road, please stay out of my town.. we got enough crazy drivers causing accidents as it is

Yankeefan130

Umm, is anything overthinking the part that these cars are FWD?? Adding that much HP (if possible) is stretching this car too much on the steering IMO on a FWD car. It would need to be an Infiniti at that rate -- RWD or AWD.

dmc79

This is a good point as well, I don't care how much power you have it is very difficult to put it down in a front drive car. The Maxima is already close to the practical limit on street tires for 0-60 times. I think the lowest tested 0-60 times I've seen for a factory spec front drive car is in the 5.5 second range. The Max will do 5.8s all day long. The extra power would really only improve higher speed acceleration, say 60-100 mph or more, but how often are ordinary drivers actually able to take advantage of that on the road? To me, the car makes plenty of power for what it is, but this could be because I didn't trade a faster car like an Audi RS4, AMG Mercedes, or even a V8 Charger for it. This is the quickest car I've ever owned. To me, this car can be made into a killer custom car, but aesthetically only. Frankly, most things you can easily do either won't change performance at all or will make it worse.

BlueSR

The new Civic Type R can do 0-60 in 4.9s stock. It is about suspension set up to minimize weight transfer for FWD during acceleration. Anyway, the limitation for the Maxima is the CVT.

dmc79

Only Car & Driver managed 4.9s with the Type R, that car has redesigned front suspension that is different from other Civics along with summer rubber that helps it maximize its acceleration despite the FWD architecture. Point is, that car is an anomaly in the FWD world, the Maxima's design is more typical. I certainly agree the CVT will limit the Maxima as well. An extremely expensive engineering project would be required to retrofit it with a 6 speed manual or even a conventional automatic to better handle additional power.

Spunnedfun

QUO

Perhaps you can swap out your ecu for a standalone. It's one of the major performance upgrades for anyone who has a modified vehicle producing high horsepower through forced induction you will be able to set it in so many different ways . Change what you want. Outside of that if you do this you can tune it and gain the most from any mod you install. With or without forced induction just advancing the timing alone you will see significant power increase.
If I could turbocharge my Kia Rio I think you can find a way to make you maxima faster.