How well did the 996 plenum (part attached to cylinder heads) flow compared to what the cylinder head would flow?

 

Not good at all. Although that 996tt part is bigger than the others (996 GT2, 997tt, 997 GT2), it's flow ranked dead last. People are adding larger TB's and splitters to this part only to overwhelm this weak link.

 

i havent ever had one in hand to see but is there ample room to extrude hone it or gotta scrap it and go sheetmetal on it? I would start with one of the other plenums and work from there.

 

We are looking at that now. My guess would be to get a 997 GT2 plenum and work from there. That is not including the WC plenum in the mix.

 

i might be 3 years behind your progress but i love to discuss what your going through and trying to find ways to make it better thats the fun part when it works=)

 

hey cjv... just to save some more weight... looks like you could taper the inside ends of the wrist pins no?

 

Alex,

We gave that consideration. When we started, we wanted to reduce the pin size by 2 mm. We calculated at 2.5 bar the motor has the flow capability for 1700 to 1800 hp. Would the case take it? Not sure, however our guess is it would not. So we decided not to go there. The next question that arose was ...... what do we believe the motor can go to without case issues. Our believe is somewhere between 1400 and 1500 hp max.

Looking at this number we looked at the wrist pins and decided dropping one mm instead of two would be the safe way to go.

We believed at these numbers, given the weight we already removed from the fly wheel, crank, rods and pistons in addition to off setting the centerline of the pistons and moving the wrist pin up into the bottom ring ....... we needed the meat in the full width of the wrist pin.

 

Simon,

I'm just trying to be polite.

With your connections with Neil, you probably know more about my build than I do.

I understand the last piece to our puzzle ....... the rods, may be shipped this week. We will probably lose another week clearing customs. We are really getting close.

 

If you look at the aluminum piece that is between the head and the rubber hose you will see the piece we will be designing and making. This is the injector manifold. We will be making a manifold that matches our head intake port and houses two injectors per port. The combined rating on the two injectors will be 1350 cc's. Only one injector will operate at the lower levels. Both will come on when required. Bottom line is great idle and lower rpm operation. The manifolds will be flange x flange to bolt from the head to the throttle body.

We will then cut down the legs on the WC Plenum at the part where the hose slides over and weld on a flange to fit to the other side of the throttle body. The hoses will be eliminated completely.

Where the single 90 mm throttle body use to be along with where the MAF use to be will now be direct piping.

 

Just insane brother.

 

The Bug Definately Bit You Chad,

but that looks like a big improvment to the 996tt intake manifold, how does it fit in the engine bay? height comapred to a stock manifold?

 

The World Cup Plenum is tight ............ but it fits. Joetwint used the World Cup Plenum in his build also. The truth be known I purchased this plenum from EVOMS three to four years ago. I don't believe at the time they were have success with it. I believe they tried it on a turbo GT3 project.

Our setup makes use of our own injector manifold which is shorter in height than the stock injector manifolds. We have the added height for the throttle body but we gain space by the elimination of the rubber boot connection. All in all we have minimal more room than the World Cup Plenum and Porsche injector manifolds.

 

Roger that CJV... I just figured I'd ask We managed so shave a few grams in that area for our NA stuff and it was worth it. Of course with the TT side of things strength is such a concern. What sort of coating are you using on those? Small detail I know

 

I read through the year that I missed regarding this thread! The ups and downs are better than daytime drama LOL Glad you're finally on the home stretch!

 

Alex,

It goes by three letters and I don't remember the three letters. I believe the wrist pin coating is referred to "Carbon like Diamonds" or "Black Carbon."

My understanding is it eliminates any gauling and overheating which can lead to bent and broken wrist pins. There is added lubrication and cooling directed to the wrist pins through rifle drilled rods. This oil also is directed to a cavity under the piston dome and then out the bottom of the pistons for additional piston cooling a la 965C motor design.