Comparison of GT2/3/Turbo engine to the 962 Engine
 

I posted this on the 997 GT3 board and thought it might interest some here as well, I hope it is not too redundant.

There is a cool thread on the Pelican board HERE where a 962 engine is rebuilt. I asked if I could use some of the photos to show that the GT2/3/Turbo engine is really a derivitive of the 962 racing engine. This is the kind of stuff that to me makes a Porsche cool, and why I can't stand the normal 997/Boxster/Cayman stuff.

The 962 engine was created by taking the aircooled crankcase and adding water cooled cylinders and water cooled cylinder heads to it. This was modified for street use in the GT/Turbo street engines. In fact, the first batch of GT3s to come to the USA still had the remnants of the aircooled crankcase casting, Porsche redid the case to eliminate these features in later production. The 962 engine uses individual cylinder heads while the GT3 uses a single head to cover 3 cylinders. The cam drive on the GT3 is a chain drive rather than gears. The oil pump on the 962 has 3 rather than 2 scavenge pumps and there are a lot of other details that are different, but the GT2/3/Turbo have Porsche racing heritage to the bone and the other Porsche stuff is pretender Porsche to me.

The GT3 gearbox is the same kind of story.

So think of this next time you drive your GT3, the engine is derived from the 962.

Below is a picture of the inside of the crankcase, note this is very similar to the GT 3 street engine except for the oil pump and gear driven cams of the 962. Note Titanium rods.

http://forums.rennlist.com/upload/im...217_medium.jpg

Below is the crankcase with studs sticking out. Aircooled or watecooled the engine is same at this point of assembly. The heads and cylinders go over the studs.

http://forums.rennlist.com/upload/im...334_medium.jpg

Below are the cylinders and cylinder heads which slip over the studs above. In an aircooled car these would be finned, here they are jacketed for water.

http://forums.rennlist.com/upload/im...809_medium.jpg

Below the cambox is shown on top of the heads.

http://forums.rennlist.com/upload/im...270_medium.jpg

Below note the oil filter which is same as seen on 906 in the mid-60's. On an aircooled engine this is where an oil cooler mounts, on GT3 this is where the dry sump tank mounts.

http://forums.rennlist.com/upload/im...544_medium.jpg

These are the cams mounted in the cambox, on the GT3 engine the cams would have sprockets instead of gears since the cams on the street engine are chain driven.

http://forums.rennlist.com/upload/im...918_medium.jpg http://forums.rennlist.com/upload/im...403_medium.jpg http://forums.rennlist.com/upload/im...558_medium.jpg

Porsche 911 heritage to the bone.

Thanks.

That is really cool. Love the twin cam setup, and the huge ports. I am surprised thought that they didn't shuffle pin the case.

Very cool. the crank is a work of art.