Realistically speaking, how much power could the stock Z handle?
 

How much power could the stock engine handle? and the transmission with a new clutch and csc.

You will get mixed reviews about this. Over the years of seeing other people’s misfortune on their Z’s and seeing/helping with tear downs I would not do anything more than 450-500 whp and 450 wtq with a spot on tune from a reputable tuner. In alot of the cases I have seen the connecting rods were the limiting factor. Longevity really depends on your right foot and how your Z was tuned ultimately. It is all in the tune so when trying to push the limits of the stock Nissan pistons,connecting rods,crankshaft is opening Pandora’s box really you will be putting wear on other components as well. A good clutch kit and the CSC fix is a must. I have seen engine failures at 300 whp and 470 whp etc it just depends on how you use you’re Z the strip,track,auto x,autocross events really beats on your Z. Doing all your general maintenance on time is also key to longevity/dependablity on our cars. I would be more worried about damaging your engine than your transmission honestly. Our manual transmissions will take more abuse and whp/wtq than our automatic transmissions.

Is that what you really want to do? Take the stock engine and transmission and just push them to the absolute edge of breaking? I hope you like spending money...

Guys have put over 600 whp to the stock engine block, IIRC. Who knows how long it will last pushing that kind of power though. Best best is to fall back a bit to more reasonable power levels where the car can easily handle it rather than being on the ragged edge or build the car to handle the power you want to throw at it.

As Quicksilvers and JARblue have said, if you're taking the Z engine (or any other engine) "to the max" you better have deep pockets. The engine build is going to be expensive. Then there are the supporting mods (trans upgrade, drivetrain mount bushings, etc).

But, yeah, some people are reporting 600+ HP. Search is your friend.

There is a handful of people pushing 650+ for a while now on the stock block/MT. Only attempt this with a tuner who has experience with these cars making these power levels - but I think I'd be comfortable going into that territory... of course it is a gamble though. I'd probably only consider SpecialtyZ at that point, and I believe he has quite a few of these under his belt.

Sure you can do it. But at 600+ whp, how long will it last? Maybe a long time ... if you drive like Grandma. How long will it last if you drive it like you have 600 whp? Pushing that much power through the stock block means the harder you drive it, the shorter the life span, guaranteed.

You know what's really crazy? Those "speed shops" that "mod" and "tune" these cars have a brilliant business model. Mod a car, they blow it up, fix it and mod it further, blow it up, you know the rest. I see those places with a line of cars waiting to be modded, and an equal amount of cars broken on the sidelines waiting to get fixed.
I work with a guy who had his GTI "chipped" and I told him but he wouldn't listen, guess what, it blew up! He assured me the "Mod Shop" guys all told him it would be fine! Don't worry! LOL.
Fortunately it was a VW and they warranted the engine 'cause you know they're kind of bending over these days.
Wonder what the Mod Shop would say to his wanting to warranty the engine their tune blew up!

HotrodZ does trackdays with with his. He's pushing over 600+ hp on a stock block.

Our friend Hotrodz has all the supporting mods for his set up and I know his tune is spot on. If my memory serves me right didn’t Sebie do his tune? When pushing our VQ37HR engines to max I am a firm believer in the faster you push the envelope the less reliable it will be.

Stock block, stock internals for now. He's planning on a built motor soon. HotrodZ pushes his Z, but he also takes care of it too.

Yea, Seb did his tune. The tune is everything on a motor when you go FI. A bad tune will give you nightmares of your credit report. A good tune, and you're a happy camper like HotrodZ.

The limiting factor is torque. If you keep the torque below 500 ftlbs. The motor lives. But once you start going higher on torque. The faster it will go BANG! That seems to the consensus.

Hotrodz is not the only track car pushing the limit. DJTodd's car has been tracked most of it's miles. He is on the stock block. It all comes down to the fuel you use and the tune. The only thing I would say is have at least 15k set to the side for the day it goes boom. Even if you build the motor things can go wrong. It is the way it is in the modding world. Pay your money and take your chances.

^thiiiss. What can get misleading is that people are saying 600+ on stock block but 99% of those people are running e85 with a serious upgrade to the fuel system. Pump gas 93 or 91 will get you a lot less.