Likemystoppie?

Here's an idea: Raise your hand if you've ACTUALLY broken down and taken apart the current GT3 (997- non face lift as there is NO 997mkII variant out yet).

I believe THAT person should speak on that engines actual componets. No?

Cupcar

I can't say that I have done that, although I have seen one apart. I am installing the 997 GT3's oil pump in an engine I am building right now using an air-cooled 911 aluminum crankcase date stamped 1967, it took very little modification to install the GT3 oil pump I might add. It is nice for an engine to have roots.

Below is a picture from the Car and Driver website of the A91 engine's oil pump. You can see what I mean about the modular construction and potential to make the engine a true dry sump.

The 4 gears to the left are the cambox scavenge pumps, the bigger gear to the right (to left of big spring) is the main pressure pump. The sprocket is for the chain drive to the crankshaft.

Likemystoppie?

Cool post cupcar!

Cupcar

Below are two images.

The top image is the one Bill posted here previously.

The bottom image is a diagram of the 996/997 GT3 engine's separate water jacket assembly. Note how the #1 cylinders (made with a Nikasil lined bore) fit into the water jacket #3 which fits up to the crankcase (not pictured). If one adds the water jacket in this image to an air-cooled crankcase, one gets something that looks very much like the A91 crankcase pictured above here.

Thus the A91 seems to be a marriage of the old split air-cooled crankcase and the water jacket Porsche designed to water cool it.

One can also see how cylinder liners could perhaps be easily added to the A91.

IMHO This A91 might be one flexible design! Here's hoping

hesperus

BINGO

Cupcar

Sad but true.

I don't think there is any debate that the Metzger 4 valve is not better than its air-cooled predecessor. It has no disadvantages I can see other than increased weight which is outweighed by increased power and better noise and emissions control.

The question in the past was is the "integrated dry sump" engine better than the dry sump air-cooled.

Now the debate continues in that vein, but the engines are both water cooled this time.

Snowboarder54

I agree 100%!!

johnnydiii

Apologies if this has been covered already but I am trying to ascertain once and for all whether the 9A1 4.0 liter in the latest GT3 RS is a dry sump motor. I can see from previous posts that this is probably a "self contained dry sump system" but I wanted to ask a couple of questions.

1) Does this motor share the same block with the latest generation Boxster and 911 motors?
2) If so, is the bolt pattern on the engine mounting studs the same as the latest generation Boxster and 911? Said another way, will the new 4.0L 9A1 RS motor bolt directly to those gear boxes forgetting output shaft, clutch and flywheel issues (although it would be nice to know if they are going to be a problem)?

I am sure you all can see where I am going with this. Here's another hint: Mid engine Porsches rule!


Thanks for any insights.