N/A Rebuild
 

Hey Z forums,
I have what I would consider to be one of the higher mileage 370z's on the road. It's my daily driver, and I'm about 3000 miles away from the 100k mark. I'm regretting never having put forced induction on, but I'm finding myself in a position where I feel it's astronomically safer to rebuild first.

Recently I picked up a heavily tuned 2006 C2S. Wasn't my first porsche, and it was in lou of building my Z. I originally intended on reselling. Well, a host of minor cosmetic and minor engine problems later and I'm permanently signing myself off. I'm posting the car to sell in about a week, and plan on tuning the Z. *Not to plug, but its a black C2S with 30k in it and a new engine replaced at 60k if anyone wants pics. Whether for interest or pleasure*

TLDR:
I have a 370z and I'm going to rebuild. I love N/A engines, but the Z can't perform on a stock block to the standards I'm accustomed. I'm trying to figure out whether the power I gain from a big bore/stroker kit would be applicable in an N/A setup, or if I'm better off rebuilding my stock block and going for forced induction.

Current Mods:
Takeda Long Tube Intake
FI non-resonated Y pipe
HKS knockoff ebay exhaust




This isn't a problem of cost or production of the most power. I understand that I can get the most out of a stroker kit and a TT, money is absolutely no object. Reliability is key to me. I can self install the supercharger as well.

My question is, if I fully opened my exhaust and sent my engine into GTM for a rebuild at 4.2 or 4.5L, could I get numbers close to a supercharger pushing 6 PSI on a stock block? I'm only trying to get up to about 390WHP. Essentially I'm confused at the compression of these pistons. If stock is 11:1 and a 4.5L would be running a 9:1 compression, is it even feasible to expect more power out of the larger engine? Thoughts, comments please. I can't find any information on a 4.5L N/A Z and don't mind being the guinea pig for dynos if it's actually viable.

I wouldn't send anything to GTM if I were you. Also, the 4.5 stroker from them is set up for boost.

Didn't GTM go out of business?

There a "Renewed" company or something like that

still wouldnt trust them

from the reading i have done, you have about the same chance of winning the lottery as to getting something from GTM. if you're looking for 390whp then your best bet is a supercharger. they make low to mid 400s. if you want higher then go turbo.

if money is no concern, i'd go turbo. i think there are plenty of people on here who have 500+ whp and have reliable cars that are done right.

Look up 1slow370z build. He was jusr a few short mods away from having 400whp on a na block, 1 your gonna need a dry sump, jun cams (282), and a awesome intake manifold. Next figure out a way to spin the motor to 9k.

So I've read. Seems like their reputation waivers a lot, thanks for the confirmation.
Will definitely go 4.2 Brian Crower IF I do. Good to know it's for boost, confirmed why I was confused about compression.


Looks like I'll probably be going the supercharger route based on above information, but that opens up options. I was always under the impression that turbo kits were jenky on the Z, but I'll definitely do my homework incase I want to go that direction. Not really looking for that 500 WHP though, even my Old Man's Z06 knocks my socks off.

Definitely saw his build. I was a little intimidated by his mechanical knowledge though, and I don't think that's something I could pursue. In fact I was hoping this topic might find me a more refined way of achieving his power.




In all, I appreciate the help. Although I've never been a boost junkie, I really want my Z to be able to perform to the limits of its architecture. I'll plan on rebuilding to a 3.7L and supercharging as of now. BUT if anyone has additional input on N/A builds concerning displacement, your input is much appreciated.

Also, this is the first I've seen of a build like such. The only 4.0 stroker kit I can find is (surprise) from GTM and for the r35 engine. Not being a mechanic by trade I can only assume that there would be technical difficulty and extra cost associated with this install.

Not only this, but he fails to mention how I'll deal with our oil heating problems. No disrespect to the original author, but is this an exaggeration? If I was already paying for a rebuild I wouldn't be hurt to put an extra $10k in to get to 400RWHP.

Talk to JWT as well as Brian Crower about sourcing a 4.0 stroker kit for the VQ37 engine

I've heard people using two 34 row oil coolers to combat the heat.

To keep it simple and reliable i would go SC the rebuild is up to you...im over 200,000 miles and have a strong engine still, but rings and bearings couldn't hurt. However i would hold off on a SC for 5 - 10,000 miles after the rebuild.

Good to note! I figured some break in would be in order, but I wouldn't have ever waited that long. I'll definitely be patient. As of now little is possible until I offload my 911 though, just for practical reasons. It's in the shop for a random check engine light they're diagnosing so I have to wait to even post it :eek:

I think before I'd spend all that money trying to push a V6 over 400hp I'd just sell the Z and buy a C5 or C6 Z06. They'll make that hp all day long with no mods and maximum reliability.

If you really just love the Z accept it for what it is and enjoy it. Trying to mod it into something on the edge of structural integrity is like owning a German car out of warranty - anyone who has ever owned a C2 Porsche will know exactly what I'm talking about...

It's more to make sure who ever did the rebuild did it right...I've had some VERY bad machine shop experiences in the past. Really a good long weekend road trip would probably be enough.

A C5 or C6 would be a easier option, but so boring, anybody can just go buy a stock vette. I'm sure most of us are on this site because we want to be a little different. There are a bunch of SC Z's running around with no problem, just don't get crazy with boost and you'll be fine.

On a side note my next DD will be Supercharged, and we all know the kinda mileage I put on. LOL

importparts pro will build a stroker motor but its close to 10k :/ I contact them a few months back. Kyle's good people

I love me some Z06 action as much as the next guy but I disagree with the line of thinking. If you're not on a budget and want to push the envelope or do something different, by all means go for it. It would be real boring if everyone went for the easiest or most common route to reach a goal.

That all being said, OP if it's your DD, stick to a proven formula.

It's all about the tune and the pertain building the motor. Take your time triple check everything and the motor will be fine. These motors can handle alot of punishment. 400 whp horsepower isn't out the realm for a na build, i figure it will cost just add much as superchargering. 9krpm Z would sounds intoxicating.

the only increased displacement NA Z, if i recall correctly, is Shamu. And that was his race car, which he worked alongside a shop with. JWT (Jim Wolf Technology) would also have a lot of information about increased displacement vq37 and cams.

Well that's a matter of perspective and a bit dismissive isn't it? I'm sure one could find Z06 owners who scoff at "lowly Nissans" just as you scoff at the "common Z06". Personally I think the C6 Z06 is a beautiful car and about as far from boring as one can get without a solid six-figure income.

The op said "the Z can't perform...to the standards I'm accustomed". The point I'm making is the 370Z will never be competitive with the Z06 or 911 GT3 or Mustang Boss 302 or Z28. If one wants that level of performance why drain one's pocketbook trying to morph a Z into something it wasn't designed to do. Unless you just want to.

I think everyone understands the flip side of that coin is some love a challenge, creating something unique and unexpected. If that describes you then "more power to you" and mod away. It can always be done. One could retrofit a GTR engine in a Z if one has the determination, persistence, and resources. It's your money and your time.

Best of luck to the op...

2016 z is suppose to have 450-500 horsepower.

Or a 3.9l 400 horsepower na

Another note the z06 and gt3 and 911 also come from the factory with an significant top notch parts, meanwhile the Z was intended to be an affordable sports car, hence takibg short cuts to reduce cost.replace those parts and the Z can hold its own, and all depends on the driver.

A N/A 350z is making 414whp with ITB and Motec so 380-390rwhp is possible. I'm building an intake system including upper and lower plenum that's kind of like ITB style but keeping the strut bar, so I'll see how much more hp I can get from it. Also, the 288 Jun cam is not needed anymore since ECU Tec is now supporting VVEL tuning and the stock VVEL is capable of doing up to 340 degree or something close to it.

Another intake mainfold project. So your saying will be like 1slow370z one off manifold?

I'll see how it performs first, if it performs well then depending on the interest I might have the team build a few to sell. :tup:

this is still all speculation, there isn't anything out there to confirm this.

If you are really hell-bent on a N/A build -- I would talk to/check threads by BGTV8 and 1slow370z.

As to "reliability", once you start this project, that's all kind of out the window...

If you just want to get the most out of it and want to make sure the motor is holding up, I'd do a compression test, tune up, and get a SC or turbo kit.

When and if something breaks after that, then worry about rebuilding it.

Or... make my dream come true and figure out how to get a A2W IC'd roots blower working on this car :tup:

With all respect I know which platform I want. I also know that I want more power. I want to bring the car to its limits, I'm not talking about a reinforced chassis, rebuilt suspension, big brakes and weight reduction. I'm talking about reliable ways to maintain the Z's feel without risking its integrity.

Is that your garage Shark? Major props if so. :tup:

Also hilarious that someone said to just buy a Z06 and OP already has one. :icon18:

I didn't say it was an ugly car, but I see them everyday, the Z not so much...i'd rather build then buy is what i'm getting at. or buy and mod...He already has the Z, why not see how far it can go with some bolt-ons.

My next DD will be a boring Chevy Truck, but will be seeing a host of mods, including a SC, Drop Kit, Wheels/Tire, Intake, Exhaust, Headers, Audio...Thus not so boring. :tup:

That's what I'm going for. Hopefully by end of year or early next year; I'm lucky enough to have a top Z shop to do the job near me.

Wish you the best of luck, my budget will only take me to 8k rpms. Maybe in a few years i can afford a dry sump and a built motor

No, not the Z06. It's my fathers and he lives close, we were putting on some APR carbon fiber aero:icon17:

I've driven it plenty though, and I really don't care for the massive amounts of power even with his limited modifications. I'm really considering a rebuild with cats, headers, and a very aggressive tune at this point in time. Seems like most other options put me at risk, especially for a DD.