powdrhound

Pretty much impossible to find 321 mandrel bends in a 0.035 wall. You may have to have it bent somewhere.

Capt. Obvious

Boy howdy is 321 expensive. I was thinking it would be maybe 30% more, but it's almost as expensive as titanium. Maybe I'll just stick with the poor man's option (304).

2fcknfst

You cannot put a price on love.

Scott.

Nice work John on the continued support and development of this platform. I'm late to the party and will post updates soon

pfbz

I definitely want to hear the new exhaust setup... Bummed I missed the track day Sunday.

powdrhound

The beauty of 321 x 0.035 is the fact that pound for pound it is the same as Inconel, actually a hair lighter. Building an exhaust out of 321x0.035 would result is a 40-50% weight savings over 304x0.065. The thin wall would also give the exhaust a higher pitch.

powdrhound

Looking forward to it. How is the car doing? Got it all finished? We are going to the NASA event at the end of July at UMC. I'm gonna run TTU in my car and possibly the 6hr enduro with a good friend of mine in his 996Cup if we can get the logistics together by then. Would be great if you could make it. Miller is a phenomenal track.

powdrhound

Sorry we missed you Paul. I'm going to wine country this weekend but we'll be back out at the end of June for the NASA event. You should come out and run the DE portion of it. Ton of Porsche guys in this one.

manimal

+1 on that!

Don't want to hijack, but I've always been curious what platform you would choose, John, if not the 996TT.

powdrhound

I don't know much about other platforms so I'm pretty sure I would stay with a 911 with a Mezger. The development work has been a lot of fun on this car but to make it what it is has required a complete replacement of everything except the actual 996 tub. It's been great to see how far one can develop a "street legal" car. I use that term loosely as the car is still legally registered but is in no way suited for street use. It's essentially the water cooled version of the 993GT2 EVO and can be ultra competitive in TTU with a few tweaks. I am in the process of working with a company that is going to design some serious aero for the front and rear. For something out of the box, I'd just get a 6Cup and call it a day. A number of my local buds have bought one in the past year and I'm on the lookout one if the right one comes up. I will always keep my car however as it's a totally different experience.

pfbz

At home tracks that aren't at 5,000' elevation, a 6cup might make much more sense, but at HPR, they are giving up 15%+ of their power with no easy way to claw it back...

Of course much less work to buy a cup car than modifying a Turbo to get the handling, cornering, light weight, high-redline, crash protection etc. of a factory motorsports car!

powdrhound

I don't think you give up quite that much Paul. A friend of mine just dynoed his 6Cup and if I recall he put down 355whp on the same dyno you and I used. I'd say that's about 20whp down from sea level #s. He's one of the fastest local 996 drivers and has done HPR at 1:53 in it on fresh tires. That's about 10 seconds quicker than the typical 6TT which typically slots in at a 2:03-07. Light weight and lots of grip do the trick as HPR is not really a high hp track. He's running his car in the NASA TT1 next weekend and I suspect he'll be able to win that easily.

Capt. Obvious

Most 304 piping used for exhausts is 16ga, I wonder how 18ga 304 would stand up on a street car? Not as light as the 321, but it would still be a decent weight savings while being much less expensive.

powdrhound

Not sure. 321x0.035 is used on turbocharged aircraft exhausts so that's proven above and beyond. Don't know about 304. My guess is it would be fine expecially on a street car and likely fine for track use also.

diverdog

Very cool build! Lots of well though out mods. I race against several cup cars that have been converted to 996 TT engines and they are very fast indeed! Seeing your dyno's has got me very excited as a 3.8L TT 996 Mezger is being installed in my GT1 class Cayman and will be done in August. Like your video from HP raceway. On my bucket list for sure.