Vq longevity - tt or supercharger?
 

Which setup do you guys think causes more stress on the motor? Gtm tt or gtms supercharger? Car has 3k miles and im planning on keeping it for a long time. Any thoughts?

Both can trash a motor with equal ease -- I don't know how much punishment the OEM motor can take (is it known? Has one been pushed to the limits yet?), but notwithstanding the extra stress of high cylinder pressure, so long as the tune is good, the motor should hold together...

Bang for the buck, probably one of the S/C kits.

Until a roots blower kit is developed, for the best low end grunt, the TT kit is the best option -- but waaay more money.

anytime you put boost into an engine that was not designed and built for it (VG, VR for example) you are going to loose longevity. that's just the facts of life, same as not changing the oil. having said that, you should be able to get 400-450whp out of a good TT kit while maintaining good driveability and longevity, just not as much as keeping it all stock

If you want to keep the car for a very long time, i suggest a low boost supercharger kit ~400 whp.

Given the same peak power output, the twin turbo kit will probably put more overall strain on your lower end; mainly because it produces more of a punch down low. The more peak torque your engine produces, the more stress the connecting rods, rod bearings, etc. experience.

This may actually be exacerbated by the fact that a turbo setup will produce higher manifold air temps than an intercooled supercharger setup (assuming roughly equal compressor adiabatic efficiency). This added heat ends up putting more thermal stress on the piston crowns and other components, as well as increasing the chance for detonation.

In practice, I'm sure the difference between the two setups is negligible. Just don't trick yourself into thinking your engine owes you any sort of "reliability" once you force feed it. 11:1 CR + boost = ticking timebomb. Yes, good tuning offsets that fact to an extent, but the engine will almost certainly fail prematurely while boosted. You're taking an already high-strung, inherently imbalanced V6 and lowering its tolerance for detonation, pre-ignition, lubrication break-down, thermal break-down, etc. Not conducive at all to motor longevity.

Any claim to the limit of any OEM engine being good for a particular WHP or boost pressure range is conjecture at best.

We can look to the 350z/G35 experiences over 7 years and many cars with tens of thousands of miles to see there can be OEM like reliability IF people control themselves. The tendency is to keep pushing the output of any kit and at some point (which varies per car), the reliability will be hurt. None of us can quantify what that means though. Does the engine only do 135,000 miles instead of 165,000 miles? 80,000 versus 100,000? Pay to play is always in effect. HP vs reliability is not a simple downward sloping straight line - more like a downward sloping gently curving line that starts to fall off steeply the farther the engine is pushed.

:confused: after reading some of this posts, i think the best bet for me would be to bolt the z? Maybe go with intakes, hfc, cbe, pulley and a tune? Or is that going to hurt the life of the engine too? Sorry for the newbie questions

in general, no. A.S.S (all stock stuff) is the best way to go. intake and exhaust aren't going to hurt anything, also getting a good tune after you get all the bolt ons you want will boost power and efficiency without really hurting anything

So all bolt ons are not really adding any stress on the engine right?

not really

Anything that adds power adds stress.

If you are worried about longevity, don't touch the car.

I would have to disagree because all bolt on parts are not making the engine work more. Its just making it breathe better than the restricted stock setup. You're not modifying the internals/or Adding f.i to it. Why would a pulley, intakes, hfc and exhaust lower the longevity of a high compression motor? Id like to know.

well you make more power by moving more CFM through the engine, nothing like F.I. but a little. and anytime you do that, you take away from the long term reliability but the difference is so minimal i wouldn't say you'd even notice the difference in the long run

You right foot determine longevity of the car... it could be nitrous,fi, or just bolt on...if you dog it out it will break. Good maintenance and take care of your car goes a long way.I would not put F.I on the car if you're worrying about keeping it for a long time. For any one that wants F.I they should prepare the *oh ***** money on the side. Bolt on won't make it any less reliable then stock. It comes down to how you drive it.

I plan on getting a beater (because I drive a lot for work anyway).

But im hoping I can put a S/C on the car with some bolt ons and make around 430whp and put maybe 5 or 6k on the car yearly and keep it for quite some time.

It goes without saying that for longevity, leave the car stock. For maximum fun and performance, go twin turbo. IMO, a centrifugal supercharger is sort of in the middle.

Just to clarify here... for the most part when you are looking at increasing an NA motor's output via intake or exhaust mods, you're going to be increasing combustion efficiency. i.e. allowing more fresh air in the cylinder during combustion. More air ==> more power ==> more combustion heat and pressure ==> increased wear on internal engine components.

Now, if you're talking about mods outside of the induction and exhaust systems (lightweight/underdrive pulleys, lightweight flywheels, etc) then you're correct. But there are some technical drawbacks to such items as well when you're considering engine harmonics and such.

Yes -- without question, FI will reduce the overall longevity of the engine (i.e., substantially greater cylinder pressure creates considerable additional stress on the entire motor -- especially rods, crank, and pistons).

On the other hand, with a bad tune, detonation and preignition can kill the motor in seconds.

Now will FI, even with a "perfect" tune, reduce longevity by 100K miles or 300K miles? That appears to be unknown.

Has anyone found something resembling the upper limits of what the motor will tolerate before breaking due to overpower -- as in, will break something even with a seemingly knock free tune?

Well even with a really good tune, fuel starvation can kill an engine in seconds. The stock fuel system sump design (ignoring having upgraded pumps, lines, etc) is not capable of fueling a car making 2x stock power. You really need a fuel accumulator or revamped fuel pickup design to safely run a ton of power over stock. I've yet to encounter any budget sports car that had such a fuel system design stock.

Evo's have this issue... my project car before that had the very same issue. I'm sure the 370Z is no exception. In fact, unexpected fuel starvation has always been the biggest engine killer I've come across while tuning turbo cars.

Uphill onramp + 0.7+ g's of acceleration = fuel starvation. Not to mention power under cornering on a road course.

^^^ I'm going on the assumption of all proper and needed upgrades for safe tune while leaving the motor untouched (i.e., larger injectors, bigger fuel pump).

I'm saying, given all that, at what power level is the motor likely to break something? I don't think that is currently known... the longevity at another 150 whp is also unknown...

Its all pretty much unknown at this point but anything that adds power will take away from the life, just jow much is the question. Full bolt ons IMO wouldnt cause any noticeable difference. A low PSI FI will take away some life but with todays cars going 200,000 miles on them would taking 20,000 miles, lets just say, really matter to most pepople? Not me as I dont keep cars much past 50 or 60K miles. The interior will degrade far sooner than the engine will.

I work for a Nissan dealership and earlier today I asked the same question to our master technician. He said that the vq motor has strong internals and that he felt a a supercharger with low boost 6-7 pounds would be ideal. He said TT is more fun but it will harm the motor/tranny in the long run. So I guess that leaves me with either supercharging the z, or bolting it up.

Go big or go home. ;)
Should know over the next 6 months what this engine can handle, especially when we see some bigger builds finish up.

There is a guy that runs the Z club here in Houston with a twin garett's putting out well over 400whp+. He has had 40,000 safe miles no probs and he by no means drives like a grandma and still curently has no issues.

Yep, if done right (from 350z research) the VQ engine does very well with forced induction. Just remember, do not go cheap when doing these types of upgrades.

And dont let dreamer play with your boost controller:shakes head:

You might go blind.

Are the VQ motors forged, or hypereutectic *sp pistons?

I have yet to touch yours boost controller yet, wait...does a turbo whistler count as boost controller? :ugh2:

Well, the unicorn blood coats the pistons,seals and rings. Also lowers the compression, so it should last at least 10 years.

Good question -- I doubt they're forged...

Anyone have pics of them? Wondering how thick the ringlands are and how high up the rings are.

Agreed but when throwing a turbo whistler into the equation the results will drasticly change. If the turbo whistler is not intalled correctly you will have tons of problems. But don't get me wrong a turbo whistled car is a blast to drive.:driving:

Woooo woooo

You guys have me worried, turbo whistler might be tough to tune.

only half life

Ford uses forged pistons in their new 5.0L 4V V8, why can't Nissan? Maybe? Hoping : )

Just get one of these and have a TT even if you dont have a TT in the engine.

http://www.pcstats.com/articleimages...GTTT_butt2.jpg

They'll put turbos on anyting nowadwys.
http://ifonlyihadit.com/wp-content/u...ter-201207.jpg

I did not know this. Oh man I see a mustang money pit in my future, man the wife is going to kill me.

Isnt the mustang the national car of alabama? LOL JK