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Depends if you have done a heap of mods to change the air/fuel ratio..

After all the mods like full header back exhaust, plenum spacer, ztube, drop in K&N filter or CAI then you can get another 10-15kw with tune i believe..

Your better of just getting 2nd hand super charger - will cost similar to changing all the above but you will have way more power..

What exactly is a 'first tune'?

Without the addition of a full replacement ECU (like a PowerFC), piggy-back air/fuel computer (like an Apexi AFC NEO) wired into your ECU, full-on piggy-back ECU (like a Unichip), or an Osiris rom tune, you cannot perform any variety of tune on a V35.

Putting a supercharger or turbocharger on a stock motor is an extremely bad idea. Pretty much every story I have read about people putting FI on a standard motor ends in tears after a short period of time.

Have a read of this in full ....

http://www.nicoclub.com/archives/350z-g35-twin-turbo-install.html

Putting a supercharger or turbocharger on a stock motor is an extremely bad idea. Pretty much every story I have read about people putting FI on a standard motor ends in tears after a short period of time.

And I can give you examples of NA motors that have given up too. Without looking hard you can find examples of FI stock block motors running 30, or 40 thousand miles after becoming forced induction. Such a general statment is just bullshit mate. Uneducated bullshit. Yes, there are motors that let go- mostly due to poor tuning, abuse, or just plainly exceeding the limits. However there are many more rolling around everyday just doing fine. Its a bit like the old N1 oil pump saga.

Plain and simple though - our very high compression motors are most certainly not built to withstand FI. Maybe with most conservative tuning, tons of fuel and a bit of luck you could do it, but for the most part, people who go to the expense and trouble of putting on FI don't do it to gain 30rwkw - they want decent power, and in order to do that you need to run timing and boost, which will result in an exploded motor. Fullstop.

The limits are well defined.

I've gained 70kw, in a very safe tune, at a boost level well under the limit.

You can just play around with Z tubes and Plenum spacers then.... I'll play with boost.

So you run about 220rwkw then I take it .... why would you even bother spending the sort of coin if you only have for that sort of power? And when you spin a bearing or create a piston inspection window in the side of your block I look forward to reading your sob story :) ..... when I had my R34 I ran a HKS 2530 on a RB25NEO and made a lazy 240rwkw @ 1 bar in an auto .... so obviously 220rwkw out of a 3.5l engine is pretty crappy.

The guy was asking for advice - yours is bad. MOST people who run FI on VQ35DEs only do so for a fairly short period of time, and then are up for significant cost and heartache - especially for non-mechanically minded people. That is all I was saying. Most people don't realise what you really need to do to make a FI setup on VQ35DEs to make them reliable. Decompression, block strengthening/machining and new crack/rods/pistons/head studs are the minimum required imho. Not to mention valve ECU/tuning, porting/manifold matching, fuel lines upgrade, fuel reg, fuel pumps, clutch/valve body and injectors upgrades etc etc ....

Ok, so spending how much on NA mods is good? Some nice $1100 Tomei manifolds for a 7 kw gain...?

I have done my work for the price some NA people have spend on mods. Thats because we built it, didn't just drop it off to a shop and say heres 10k- do it for me. Its not about how much we spend on cars anyway- its about making our cars personalised, our own. Whatever you spend- $200 or $100k. If the R34 was so great, maybe you should have kept it?

Please - tell me what my advice is, becuase I can't see anywhere above where I have directed advice at OP. I'm just countering some closed minded opinions based on no real world expereience - just stories on the interwebz

Building the engine to suit is probably the safest path, as power can be addictive, and everyone will always want 'just a bit more'. That said I have a friend running 9psi via a stillen supercharger on VQ30DE A32 Maxima with stock internals. He has had it for about 4 years now, and doesn't exactly drive it nicely.. no engine issues yet. Who knows if it will last, but it certainly didn't become a hand grenade after a few thousand km.

No Tony, you can't run Nistune on the V35 ECU sadly - especially given I am friends with and live under 5km from Pete Leibig - the guy who owns PLMS, makes the boards and tunes cars too ....

hey andrew, i am gonna install the exotic speed catback exhaust in a couple of weeks, do i need to get the V tuned ???

Most people i know that have installed catbacks don't get a tune, but i'm not 100% if it will do much

hey andrew, i am gonna install the exotic speed catback exhaust in a couple of weeks, do i need to get the V tuned ???

Do you have an SAFC or other kind of computer? If you don't, then there is nothing you can do to tune your V. But either way, not really.

After I had done all my mods I fitted an SAFCII and gained 10rwkw with an air/fuel tune, but there was a fair list of mods done in order to have that effect.

Short explanation: Exhausts do not require an ECU tune. The reason why people tune their cars after bolting on their simple modifications is to add to the tally of gained power through the less conservative tuning compared to stock maps.

Long explanation: If the exhaust had any influence at all, it may possibly be from changing headers in which the gases arriving at the wideband O2 sensors thereafter would be potentially different but that difference would be absolutely minuscule. If you want real accuracy in measuring air/fuel mixtures, you would need to put a wideband O2 sensor on each of the ports at the headers to monitor each and every single cylinder individually as the ECU could then tailor the fuel/ignition parameters for each cylinder individually. I saw this done at a MoTeC seminar and I must admit, it did look cool and the results were useful from a racing point of view. But the gains from it were that minor that while it helps in a racing situation, it does nothing for the average street enthusiast like us.

In my time of installing and tuning engine management systems, there has never been a situation which has warranted me altering the maps because of different pipework.

Edited by The Max

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