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