Chad; Oval bearings?! Can you elaborate on that one. I am not aware of the technology sir.

 

Hi Gary,

This is a special bearing which is not new to NASCAR or F1. My understanding is when a bearing is stressed it actually ovals in shape. These bearings preclude this allowing for a true circular rotation and superior oiling which allow for higher rpm's.

 

Note the 996tt head between the two banks of valves on the left and right side. These are oil grooves. The Cup heads do not have these grooves.

Here are the same grooves on Stephen's 996tt heads.


Does anyone know why? They can be machined into the Cup heads, but what is their purpose? Stephen, do you have an answer?

 

perdy

 

Those sir are for the EGR air system. They pump air from the air pump through the intake port through the head and mix the exhaust port with the air being pushed in to lower the CO level. If you are trying to maintain 50 state legal you are going to need to machine that back in. I would bet the GTIII heads do not have that little port on the top??

 

Stephen,

Thanks for the reply. To your credit, my tuner did not know what these were.

What do you know about oval crank bearings?

 

The concept is that under high RPM the bearings will start to oval. This is at VERY high RPM. The setting of the oval bearing then pulls its self round under these conditions. It counter sets it if you will. I have never used them because I am not building motors that do 14K rpm. I personally do not know how that could be a factor if the rod bolts are strong enough. Then again I have never really seen the bearings of an 14K RPM limit car. The other thing to consider are these motor are being rebuilt almost every race. So longevity on street use would be a concern. Remember the f1 circuit is more concerned with getting through one race then 15K miles. They look for reliability, not longevity.

 

Stephen,

Thanks for your input. I guess we will find out how well these oval bearings really work. They turned the crank rod journals down to approx. two inches. The rods are also a little beefier on the bottom end.

I really find it amazing how Porsche provides so little information and few people really know anything about these motors. Again, your help is really appreciated.

 

You are welcome!

 

CJV,

I applaud you for your dedication and for not giving up on attaining the goal you had set.

I have been following the build-up for quite some time and have been looking forward to seeing it running in its final configuration.

There is some rather "new" ground breaking technology that will become mainstream very soon in the realm of engine technology. A good friend/Porsche Tuner/Engineer has developed what is termed an "Adiabatic Engine". It is in simple terms a "self-cooling" engine. He is currently extracting 350hp/liter and his 993TT prototype car is developing 858RWHP right now in a 3.8L configuration.

If you are interested, I could pass along some information for you.

 

vrus,

You and your friend are over my head. I would definitely be interested in learning more. Producing 350 Hp per liter is simply amazing.

 

CJV,

Here is a link to a recent business article published in Florida. He is using Florida as his main office and travels back and forth. He still maintains his shop here in Scarborough, Ontario..

http://www.bizjournals.com/jacksonvi...12/story7.html

I made a little error in my previous post... His 993TT is only PARTLY converted to the adiabatic system and is making 858RWHP right now.. His 3.2L race car (which was his prototype/development car for this technology) is currently making just over 1200HP (at the crank).

This is some interesting reading.... Here is a link to the patent documents I scanned:

Adiabatic Engine Patent Documents

I will be building one for myself so I may see you at the next shoot-out.

 

Wow...read the article. That will be amazing if it bears out to really improve the efficiency to 85%...

 

It really is amazing stuff..

His race car which he used to design and test this technology is usually parked in his shop. It is a tube frame so you can see all around the engine. There is no radiator, no fan or any other type of cooling system on this car.

He starts up the motor, lets it run for about 2min to warm it up to operating temperature. The block is COLD. It actually forms condensation and drips water while it is running. You can put your hand on the block and he revs it up to 5,000RPM and holds it there.. No sign of heat or warmth on the engine block at all!!!

Not to mention the reliability... He has had this thing running for almost 3 years in its last configuration and has never had to tear down the block to replace anything. It runs at every road race event we have and he whips around GT1 cars on the track like they are standing still.

If you guys are ever up in the Toronto area, let me know and I'll arrange a "tour".

 

Is there a website for this tech.?