Direct Injection!

Brazilbro

Doesnt adding D.I. make it harder to upgrade your fuel system? Isnt that the problem they are having with the BMW I-135 running out of fuel past 6k

tvfreakazoid

Who knows. Even though I asked the question I really don't know what it does. Or how it generates more power. I just read it in various magazines.

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Mudders milk

AndreZ Cadena

Oh WTF! This car will get better in a year and It overheats at the track!? shouldve kept my friggin 350Z....

TipsZ

In Stock it overheats? Can you expound please?

370Z Purist

It keeps the fuel spread out nearly perfectly in the cylinder, encouraging more complete combustion, which increases efficiency in the sense of more power (since more fuel burns) and cleaner exhausts (since more fuel burns). This is versus mixing fuel into the air at the throttle body area (well, a bit more past it). Fuel can "clump" so there are concentrated pockets of air and fuel mixtures, making combustion uneven and inefficient.

In general, it is significantly easier (chemically / stoichiometrically) to burn perfectly vaporized fuel than if were in a liquid state. Gasoline aerosolizes in air though, so it's difficult to observe in real time.

Direct injection is damn near the best thing you can get in any engine. But as mentioned before, a bad fuel pump or atomizer / injector will ruin any possible horsepower gain.

A good DI system provides good gains across the band, but particularly in high RPM ranges, giving good top end power (obviously, fuel has less time to spread out, so a good injector can do this better than a premixed engine, like the sequential mixer we have in the VQ37VHR).

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-Phil

"Since one of my brake light bulbs just went out, the forum told me that my piston rings are about to blow."

drisko

I believe the DI systems also make more power because the car can run a slightly leaner A/F ratio (the fuel amount is more precisely controlled).

Shane D

Not sure if anybody here watches Autoline Detroit, but it is a quick daily dose of auto info. Todays story mentions that Nissan is developing a new fuel injection system, incorporating Dual Port Injection. Should debut in 2010.

Pretty cool system that give you six to seven minutes of auto news each day.

Check out:
Autoline Daily

Shane D

Lug

I'm no expert but I assumed you still used injectors and could just swap to larger ones. Then your only limit is the flow rate of the fuel pump itself.

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azn370z

Maybe the 40th anniversary model will get the direct injection when in comes out in Jan? The 35th anniversary model got the new v6 while the other z didn't until the following year.

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2010 k23
H&R sport springs / Spc rear camber arms / SSR SP1 / Berk cbe / Varis cf lip / Nismo S-Tune side skirts

ianthegreat

QUOTE=Brazilbro;45183]Doesnt adding D.I. make it harder to upgrade your fuel system? Isnt that the problem they are having with the BMW I-135 running out of fuel past 6k[/QUOTE]

Yes, it makes regulating fuel much more difficult. Custom intake manifolds can solve this, but you're looking at a completely new control system/ecu for the car. Horse Power Freaks are known to do this and are working on a package for the 335i currently.

The n54 isn't necessarily running out of fuel past any rpm range, you're probably thinking of turbo efficiency. So far the n54 is limited to around 440rwhp in it's current set up (stock turbos). Time will tell if they can push that limit with the stock turbos/fuel system. One company has ported the stock turbos and achieved 500rwhp+ on the stock system, but I think that's pushing it a bit.

In reality, turbo upgrades are right around the corner with all the new flashes available. Hope this helps! :]

Additionally, a SC'd or Turbo'd VQ with DI -

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