DFI Engine Block Info/Rumors

[blue72s]

A few interesting tidbits were circulating the internet forums (RC at Rennteam is particularly reliable with regards to Porsche in-house info) that I thought would be worth sharing.

Supposedly the 997 and 987 DFI engine will be of lower displacement across the board and have a wet sump, evidently 997 Turbo and 997 GT3 included. If true, this may foreshadow the end of the 964 based split case dry sump engine. The new DFI block will not be based on the M97, which, again if true, would portend a new block.

[Steve@Rennsport]

Originally Posted by blue72s

Supposedly the 997 and 987 DFI engine will be of lower displacement across the board and have a wet sump, evidently 997 Turbo and 997 GT3 included. If true, this may foreshadow the end of the 964 based split case dry sump engine. The new DFI block will not be based on the M97, which, again if true, would portend a new block.

Late last year, I heard an unsubstantiated rumor that all of the future engines were going to be based on the 996-997 motors and the current GT-3/GT-2/TT engines would be discontinued to save money.

Until I hear that firsthand from a reputable source, I'll discount this as internet BS but I hope its untrue as that IMHO, would be an unmitigated disaster, based on what I've seen to date.

[Porschekid962]

Rumors are like assumptions. I just cant wait for the flat 8 in the back of a 911.......

[930gt-40r]

Imagine the cylinder liner and blown head gasket problems on that motor when pressure is introduced (or high compression)? Kiss Porsche motorsport *finishes* goodbye with that engine.

[blue72s]

I think some of you have misunderstood me. M97 is the run of the mill 996-997 motors.

The DFI block will not be based on the M97 (run of the mill 996-997 motors).

[930gt-40r]

I hope you are right.

[euro911sc]

I'm ig-nor-ant what does DFI stand for?

Thanks,

Michael

[1982911SCTarga]

DFI = Direct Fuel Injection. It's the hot, new thing.

Still living in a CIS world ...

Brian

[petevb]

Originally Posted by blue72s

A few interesting tidbits were circulating the internet forums (RC at Rennteam is particularly reliable with regards to Porsche in-house info) that I thought would be worth sharing.

Supposedly the 997 and 987 DFI engine will be of lower displacement across the board and have a wet sump, evidently 997 Turbo and 997 GT3 included. If true, this may foreshadow the end of the 964 based split case dry sump engine. The new DFI block will not be based on the M97, which, again if true, would portend a new block.

I think it's high time that Porsche went to a new architecture for the GT3/ turbo motors. Yes, it's clearly the best thing Porsche has going other than the CGT, but the design is long in tooth and that shows when one compares motor power to weight ratios.

Because the GT3 motor is based on an old design and has water jackets, etc added after the fact, it actually doesn't stack up very well with more modern machines on a power to weight bases- most of the competitors beat it by small to large margins (997S, M5, Z06, etc). If Porsche builds a new motor based on Carrera GT technology (already a few years old) you could expect the new GT3 motor to drop ~150 lbs from the tail of the car for the same power output. I suspect this is what's needed to hand it to the R8s and Ferrari 460s and keep the rear engine platform viable against the newest competition. So more power to them- by all means, make a new motor.

What I don't like to hear is no dry sump. Perhaps you can build a race motor that doesn't need one, but if this is a sign that the bean counters got their hands on the project this will be a huge step backwards. A step in that direction would virtually insure that I'll never walk into a Porsche dealer...

[euro911sc]

Thanks. hehehe I thought Motronic was the hot new thing

Originally Posted by 1982911SCTarga

DFI = Direct Fuel Injection. It's the hot, new thing.

Still living in a CIS world ...

Brian

[blue72s]

Press Information, June 6th 2008

Porsche 911 Carrera / 911 Carrera S (Coupé and Cabriolet)

Weight down, stability up – the engine block
Despite their more sophisticated and complex technology, the new power units are approximately six kilos lighter than before. A two-piece crankcase with integrated crankshaft bearings is perhaps the most significant change in technology, replacing the former four-piece block with its separate crankshaft bearing housing. The advantage is not only a reduction of weight, but also a smaller number of individual components. At the same time Porsche’s
engineers have enhanced the thermal and mechanical stability of the engine, making it even more robust by converting the design and configuration of the cylinders from open- to a closed-deck layout.
This means that the cylinder liners so far freely exposed around the cylinder gaskets are now connected with the housing by a top plate comprising the coolant sleeves. In particular, this helps to give the cylinders even greater stability in their shape and design, always remaining perfectly round. Two further advantages are the reduction of oil consumption and, thanks to less friction, even greater fuel economy.
On both the 3.6- and 3.8-litre engines, both the crankshaft and the combustion chambers come in brand-new design. Stroke on the 3.6-litre has been decreased by 1.3 to 81.5 millimetres or 3.21”, bore is up from 96 millimetres (3.78”) to 97 millimetres (3.82”).
The clear focus on even higher engine speed demonstrated by the new engines comes out even more through the modified dimensions of the 3.8-litre Boxer engine with stroke reduced from 82.8 millimetres (3.26”) to 77.5 millimetres (30.5”), while bore is up 3 millimetres (0.12”) to 102 millimetres (40.16”).

Reflecting these changes, the effective capacity of the engines changes only by a small margin, 18 cc more on the 3.6-litre adding up to 3614 cc, 24 cc less on the S-engine reducing capacity to exactly 3.8 litres.

Fewer moving parts – new timing chain drive
The new engines no longer require the former intermediate shaft serving to drive the timing chains. Originally this shaft had the task to reduce the loads acting on the camshaft drive.
Now, through the use of new, highly resistant timing chains, there is no longer a need for such an intermediate shaft, moving masses and the weight of the engine being reduced accordingly.

[blue72s]

Here is a video link
http://ca.youtube.com/watch?v=fv53RbvgfGc

You can read more about it here:
http://www.edmunds.com/insideline/do/News/articleId=127890#2


Throw a last year's engine on there and the room would be full of smoke!

[kenikh]

Bloody hell, that motor sounds, dare I say, DELICIOUS?

[911 tweaks]

that sound is intoxicating... I am sitting here with a dry mouth in amazement & wondering how can I get one of those engines into my tub... ;-) WOW

[sww914]

No main bearings= disposable engine IMO. Throw it out and get a new one like a microwave oven.

[blue72s]

Originally Posted by sww914

No main bearings

Read the Press Information posted earlier in this thread.

[sww914]

OK, integrated crankshaft bearings. Replaceable?

[rvanderpyl]

I don't think that means the bearings are part of the block, but rather the bearing carrier is, just like the old air cooled engines rather than as a seperate carrier that holds the crank and is then bolted into the case.

[David]

Now if I just had $100K lying around for a new DFI 998

[blue72s]

As from MY2010, the turbo will no longer use the GT1 block, which has been confirmed via spy photos…





I have seen the Carrera engine sketches on the 997-2 PET at my local Porsche dealer today.

PET shows that the bearing carrier is part of the block (8 main bearings) but the main bearings themselves are shells, not integrated as wrongly reported in the latest issue of Excellence:

Porsche says the Carrera’s 3.6- and the Carrera S’s 3.8-liter engines are totally new, starting with a two-piece crankcase with fully integrated crankshaft bearings instead of the previous four-piece block with its bolt-in bearing housing.
That may alarm those who think about engines in terms of rebuilding them

http://www.excellence-mag.com/art1/art1p1.html

Excellence should have known better .

I have asked the parts dept to get me the length of the con rods as I’m interested to know what is the rod ratio of the new Carrera engines. However, the PET states that the long-stroke 3.6- and the short-stroke 3.8-litre engines share exactly the same con rods (same part number).

Anyway, the 9A1 block looks very good. I will try to post the sketches tomorrow or so.