I have read one persons comments on a BMW board claming the new 09 DFI 997 are gaining most of the 30 hp increase not from DFI but from new heads, cams, exhaust, headers etc...I think this guy is getting the X51/parts and its approx 30 hp confused with the 30 hp increase for the 09s and DFI. Anyone know if there is any truth to this?

Thanks.

 

I think every aspect of the engine contributes to the overall product --so I think you both are right .

DFI + New parts = More Juice .

 

I know DFI improves hp and torque pretty much on its own but I also relize it will certainly require new parts ie a new ECU etc just to control the DFI, but I have not heard the the 09 DFI 997's are getting new cams, exhaust etc and/or that's what's responsible for the majority of the power increase. I have done quite a bit of research on DFI and the auto manufactuers are adopting this technology for its lower emissions and the extra power is a wonderful fringe benefit.

I can go on and on listing many great articles and research docs but here's how DFI makes more power in a nut shell:

Advantages of direct fuel injection
Combined with ultra-precise computer management, direct injection allows more precise control over fuel metering (the amount of fuel injected) and injection timing (exactly when the fuel is introduced into the cylinder). The location of the injector also allows for a more optimal spray pattern that breaks the gasoline up into smaller droplets. The result is more complete combustion -- in other words, more power from each drop of gasoline.

 

I think most of it is from the DFI..according to all the tech papers I read it should be worth 10-15% improvement in power. I am sure though other hard parts are going to have to be optimized to take advantage of this. With DFI the fuel is being directly injected into the combustion chamber (head change right there)vs. being injected before the intake valve, as well as the cam timing changes that would be necessary to take advantage of this setup as well. Remember most intake manifolds today are dry manifolds, meaning no fuel runs through them, but lower intakes do have the fuel injector rails along with the fuel injecors themselves. So I would imagine there would be a change there as well.

According to some of the Ford boards I wonder over to, the Mustang is going to get a 5.0L DOHC V8 with VVT and DFI later in the year for 2010 pushing horsepower to over 400 while getting better mileage and run cleaner than the older 4.6L 3V.

Dave

 

I guess we'll just have to wait & see.. but as to changes in the engine, its reasonable due to the DFI..
It will really be interesting to see an '09 carrera S with the x51 package..

 

They come with a IPD Plenum

 

 

I understand DFI alone is easily worth 10% power boost, as has been demonstrated in most applications, i.e. 355 to 390 on the 3.8L, without any other changes, so Porsche is likely to be either sandbagging or backing off a bit on thepower so they can progressively add power a bit at a time over the next few years, as per their normal practice.

 

Porsche just sent me a booklet about thier involvement in reducing emissions and there is a great section on how DFI does this and also increases power....it came with the new Christophorus.