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Cayman The Destroyer!
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Discussion Starter #241
Well it's really been an up and down year for this project. Great progress was made and I got some time in the car. The dry sump works great, solid oil pressure everywhere on the track. Central radiator and new aero is very nice and the engine is super responsive and makes a ton of power, up to 700WHP at only 1.2 Bar.
But what's the catch? issue #1 is that even at just 1 Bar the block is distorting and the heads lift enough to cause combustion gases to leak into the coolant. It causes the cap to lift and spew water onto the track. After 5-6 laps it starts to overheat. Not a good thing. We could try to O ring the block but the correct solution is to drop in a 996 TT based 3.8L Mezger. Vision is going to swap it out in exchange for my race built 4.0L M97. Fortunately Albins makes the correct bellhousing and we already have the necessary dry sump stuff in the car. Minor exhaust and intake work but much easier than dropping in a Chevy. One less piece of a Cayman and one more piece of 911 DNA.

BTW one of the guys that races with us has a Cayman with a NA GT3 engine and tranny. It sounds sweet!

Problem #2 is breaking axles. 600+ lb/ft is tough on the drive train. Unfortunately no race axles exist with the right type of trigger for the ABS. So custom axles with 911 tranny flanges and the right triggers are being made.

I have faith that 2020 is going to be a good race season!
Final M97 Dyno large.JPG
 

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I woke up this morning and for some strange reason I thought "I've not heard anything about Diverdog's Cayman for a while" and there is was in my inbox.?
 

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I spent the slow moments at work going through this thread.

I have to ask, and this probably shouldnt be something to think about at this point, but Im going to ask anyways...

If you could go back and start over, what, if anything, would you do differently?

Right now you have an absolute monster, and I cant wait to see it in person. I might have to make it a point to go to some POC events
 

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Can't wait for more
 

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Cayman The Destroyer!
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Discussion Starter #246
I spent the slow moments at work going through this thread.

I have to ask, and this probably shouldnt be something to think about at this point, but Im going to ask anyways...

If you could go back and start over, what, if anything, would you do differently?

Right now you have an absolute monster, and I cant wait to see it in person. I might have to make it a point to go to some POC events
No way I'd do this again! LOL I'd just buy a cup car and go racing!
 

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Cayman The Destroyer!
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Discussion Starter #247
So it seems that almost all of the stuff available to increase power for 996 and 997 TT's are bolt ons focusing on better intercoolers and bigger turbos for street applications.

Not many vendors offer stuff to increase internal breathing. Fortunately Protomotive does have a way to greatly improve breathing and cams to move the power band up the RPM scale a bit. It seems that the intake manifold is a major airflow issue. The solution is to use a modified GT3 manifold. The TT heads are ported to match the manifold and the combination makes a huge difference in breathing above 5,000 RPM.

Shifting the power band up and reducing the torque at low RPM is good for preservation of the gearbox.

By Porsche standards the cost for the ported heads and cams are very reasonable. The intake manifold is another story, the word obscene is appropriate to describe the cost.
Fortunately the existing intercooler and turbos from my car are a great match for the new engine.

The 3.8L TT should make a reliable ~800 WHP @ 7,200RPM on 100 octane race gas.
 

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Cayman The Destroyer!
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Discussion Starter #248
The modifications are coming along slowly. The critical path item is the new bellhousing. The kangaroos are hopping slowly at Albin's down under! We should have it next week.

There are a couple of additional side benefits to switching to the Mezger. The engine crankcase is much shallower so it will allow lowering the engine and transaxle at least 2". A very nice improvement in CG and axel angle. Better handling and much less stress on the CV joints for no extra cost.

No I didn't have the GT3 intakes painted to match the car. It's a shame they won't be visible once the engine is installed.
267165
 

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Cayman The Destroyer!
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Discussion Starter #249 (Edited)
So after two years we are giving up on getting the DSC shock controller to work with the MOTEC system in my car. I'm disappointed because I drove a race prepped 997 with the DSC and Tractive shocks and it had fantastic handling. DSC can't provide the CAN protocols so that we can transfer the needed parameters. However there is a new Tractiv controller that is completely stand alone and is also adjustable on the fly from a control panel in the car. DSC is providing the new controller free of charge. Only power and ground connections needed. No CAN buss.
It is not as sophisticated as the CAN based controller but it should be plug and play.
 

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Cayman The Destroyer!
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Discussion Starter #250
No car yet but no racing either! Waiting for the bellhousing to be shipped from kangaroo land. Mezger engine is going together. This is the 3.8L block with 12mm studs. (10mm is stock size)
 

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Cayman The Destroyer!
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Discussion Starter #252
But I would have been driving it for the last 3 years! LOL I hope this version of the car will be reliable and be fast enough to compete with any of the factory racecars
 

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Cayman The Destroyer!
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Discussion Starter #253
New front end coming along. Fender vents molded in, center radiator opening and hood duct. Splitter still needs to be curved up in the middle to insure enough airflow under the car under brake dive.
 

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Cayman The Destroyer!
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Discussion Starter #254
Side pods have a 935ish flavor. They provide space for the rather large rear tires, air filters and air inlet for the gearbox cooler, the rear isn't the prettiest but it should get the airflow job done. We will be adding a screen in the inlet as the air filters have been getting beat up by track debris.
 

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Cayman The Destroyer!
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Discussion Starter #256
Wheels are 11" X 18. Tires 280/650 slicks. There is room for a 12" wheel and wider front tire if needed
 

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Cayman The Destroyer!
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Discussion Starter #257
First attempt at bending the splitter lip. Going to make the bend a bit wider and taller.
 

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Wait a tick, is that the gen 1 or 2 front end? It initially looked like the gen 2, but now I'm looking closer and it looks like the gen 1 with a boat load of fiberglass work?

I've got the gen 1 and can get a 315 A7 on an 11 to fit with no issue, but to step up from there is really really tight....
 

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Cayman The Destroyer!
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Discussion Starter #259
The front bumper and fenders started life as Getty fiberglass 997 Cup car parts. Vision filled in the side radiator openings and enlarger the center opening when we changed to a center radiator
 

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Cayman The Destroyer!
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Discussion Starter #260
The kangaroo's finally hopped all the way to the USA!
 

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