Rollei Boxster 24 hours of Sebring Prep Update

Chad has been very busy prepping the car so I will give a quick update. In addition to the normal maintenance for a 24 hour race the following changes have been made: We had no confidence that the Boxster 5 speed transmission would survive 24 or more hours at Sebring. This led Chad to installing a Cayman S 6 speed transmission. This forces the axles to changed as well, which is also good for durability. Chad snapped one of the old axles at the HPR PCA club race which took place right after the WRL race at HPR, so I guess we made the right decision with this. The Cayman transmission is very sturdy, and has a much better and more reliable shift mechanism, once all the rubber bits are removed. I swapped out the gear set to a close ratio setup from Guard Transmission. I also added a Guard LSD. Chad has also installed a Tilton Clutch and (much) lighter flywheel. I am hoping this doubles the speed of the upshifts. We also were not happy with the SPB shocks (MCS) and knew that they would not perform well at Sebring. We got a new set of MCS triple adjustables which allow much stiffer springs and a bigger range of adjustability, as well as offering the durability we'll need at Sebring. The installation of the fancy shocks does incur a weight penalty with WRL, but the Cayman transmission and axles should take up all the penalty so we will not have to run ballast. Chad added a bunch of lights, including Litronic headlights, because Sebring is not well lit and the race will feature something like 12.5 hours of darkness. The lights and driver cooling system add up to a lot of alternator load, so Chad has fabricated a cooling system for the alternator. There is a shop down the street from me that does blueprinting of the alternator and starter. We also have yet another different tire setup with larger Hankook RS 4's Chad fabricated a quick release oil fill up device so we won't waste any time with oil top offs. He also installed quick disconnects on the brake calipers so we will handling any pad changes by changing the entire caliper. Further improvements have been made with the Livestream gadget and the radios. We are scheduled to test at HPR next week. There we will get the handling checked and make sure all the new drivetrain stuff works the way it should. We'll be using the same three driver team that we had at Daytona and HPR. That will be physically difficult so all three of us have been getting some exercise in preparation. I will post another update after testing next week. Chris Cervelli

Nice - the close ratio gears is something that is really intriguing, I’ve kind of thought in these underpowered motors, re-gearing the box may be a better way to get more pull than trying to add HP - guessing that gearbox has a lot of money in it as this point. A lot of really nice parts and ingenious stuff elsewhere. Hard to go too wrong with Tilton clutches and MCS dampers and I love the QR for swapping the caliper. The whole build looks very, very tidy. Can’t wait to watch it in action and thanks for the update.

Would have loved to check the car out at HPR PCA races last month. Didn't know this car was there. Also, absorb any knowledge I could from you guys. HPR is a blast! As always, amazing work. Thanks for sharing.

Thanks for the update !!! Hard core........

i am constantly and positively amazed by people that do things like this. i didn't know you can put a different transmission on this car.

Couple things I can see now that I am behind a computer that would be cool to get more info on: 1. I see the potentiometer on the shock - a log and quick synopsis of the data from you would be really cool. 2. The heat shielding on the headers is dope, where do I get ? 3. Looks like a fuel surge tank in the frunk, interested to know the why on that. 4. More info on the clutch / FW / TOB please, I would dig a clutch with like half the travel of the stock one and there looks to be a good weight reduction there. I always have a ton of questions, even though I know you're busy - I ask anyway

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1. Shock potentiometer data has some utility. IMHO it is not nearly as useful as everyone pretends it is though. I will try to post a screen shot and explain, but it just isn't that interesting. 2. I will ask Chad about this. 3. The surge tank is necessary to allow the fuel system to consistently use all the tank capacity, meaning that if you were to run the car out of gas under race conditions, there actually is no gas left in the tank. This is really hard to achieve. The stock fuel pump is an abysmal POS and lasts only a single race (if you are lucky). The surge tank contains a real fuel pump which generates the fuel pressure. The stock fuel pump is used only to move fuel at low pressure into the surge tank which is a job that it is capable of doing. The surge tank also gives a hard warning when you are just about out of fuel, and contains enough fuel to complete the current lap and get to the pits for refueling. 4. The clutch/flywheel setup is from AASCO in CA. They make the flywheel and Tilton makes the clutch. This is similar to the clutch used in 997 and later Cups. The benefit is a greatly reduced moment of inertia, and reduced pedal travel as Zbomb mentioned. The reduced MOI of the clutch discs greatly decreases the load on the transmission synchros, which means the driver can upshift much faster. The downshifts are easier too, although there usually is no reason to hurry on the downshifts. The reduced MOI contributes a little bit to acceleration, and the car can use all the help it can get there. The close ratio gears raise the average RPM over a lap which is certain to raise the average available power as well. With the closer gears it is less likely that there will be corner where the engine rpm is below the torque peak upon acceleration. The stock gears are way too tall for racing with ~200 rwhp anyway. We cannot use a 175mph top speed. Chris

This is really awesome, and getting to experience full on 24hr race has to be so much fun (and exhausting).

I plan to come out to watch OK if I stop by and check out this jewel in person? Rich

Chris and Chad appreciate the prep updates. Looking forward to watching the race.

awesome build and thread, thanks for sharing so much of the details!

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The heat shielding on the headers is installed by Headershield, which is part of the LN and Bilt group of companies. You send them your headers and they install the stainless steel insulated metal wrap. It is basically spot welded onto the headers. It works marvelously and holds in significant heat. It increases the performance of the headers according to my data.

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Absolutely, Come on by and visit.

The car is finished and ready for the race. We test tomorrow, but I had it out in the business park last night to set the lights up and the clutch and gearbox combo is absolute magic. It revs instantly and the ratios are perfect. I’m looking forward to what could be an epic race.

I am very impressed by the car. For guys wanting to go reliably fast in 996s... there is gold in the makeup of your car. Good luck, have fun and go fast.

I drove the car at HPR this morning. The new alternator was not working right so I only did a few laps. I got into the 2:02's easily so it's clear that the car is considerably faster than it was at the HPR race back in August. The pictures don't do it justice. The car looks so right. Chad is going to swap back to the old alternator and then the car goes onto the trailer on Friday. Everything else seemed to work well so I am confident for Sebring. I could tell we have a complete reset on the handling. The handling was ok with the default settings and will only improve with tuning. Chris

Cant wait for the livesteam. Good luck.

The Aaso flywheel? I assume it's a single mass lightened Flywheel? Have you had any issues with these on M series motors or trans? Great Build! Looking forward to seeing it in action

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The live stream URL has been generated on my YouTube channel. Here is the stream link: You Tube Copy of the information on the team as posed on my FB page �The Racher Rennstall #211 Rollei Tribute Livery Endurance GP2 Porsche Boxster is en route to Sebring International Raceway for the first ever 24H endurance race held at the famed Sebring track. This is a once in a generation amateur race event, and the ultimate test for a club level team. The car has been prepared to a factory level standard to ensure we have the equipment to complete this brutal endurance race. Our whole WRL program this year has been targeted toward, and in preparation for, this event. We are not running the WRL COTA championship race this year, because in our minds this is the prize. This race is not on the calendar for next year and will most likely never be run again. We will have our Sentinel in car video system up and running for the whole 24H event with live YouTube streaming with live chat beginning around 11:30 am eastern time on Saturday, October 30, and ending some time after the checker on Sunday October 31 at noon at the link below. We will also be providing our feed to the Driver�s Eye team for use in the live broadcast on FB and YouTube. Johnny Brewer of CTS will be monitoring our live feed and ensuring it stays up for the whole event. The driving squad is the same as the last two events with Chad ***, Chris Cervelli, and Adam Jaspers all sharing the duty of bringing the #211 to victory. This group of drivers is really working well together after three races and I could not be more proud to share the duty with these guys. We have a great team of professionals for our crew ready to bring some Rocky Mountain racing know how to the grid. I hope you enjoy the action, come what may.�

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Yes it is a custom manufactured by Assco steel single mass flywheel for the M96 series engines for use with the Tilton 7.25� twin plate clutch. This is my first time using this package but I am impressed with it so far. In testing it appears spot on for a race clutch setup with the Cayman S 6 speed Getrag gearbox.

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The alternator swap fixed the problem and I night tested the car at full song in the industrial park. We are good to go.

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Thanks for the response.. I always thought single mass lightweight flywheels were a no no on m96 engines due to lack of harmonic balancer? I may be way off though.. Good luck, Kick ***, take names!

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You may not be way off when talking about street engines, I don’t know. Although our engine is a stock 2.5, it is operating in a narrow window of maximum rpm in a racing environment. Although I did not have lengthy discussions with Aasco about harmonics, I trust they know what they are doing when offering a racing flywheel for a racing clutch. Also, intuitively the short stroke crank and low horsepower would make the 2.5 less vulnerable to harmonic stress than larger higher power boxer 6’s. We will find out, but I am not worried about it, its effect on the gearbox, or the IMS.

I believe I have read there a fluid dynamic balancer avsillable in the market now. that would worth looking into.

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thank for info Chad! Good luck and I�ll be watching!

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that is interesting stuff also� maybe start a new thread so we can discuss

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What indications are there that a damper would be useful? Chris

I'm really excited to watch you guys, I could spend days poking around the car at all the details. I'm going to give Aasco a call, If I'm going to run the motor for another year, I think the clutch / FW setup may be a worthy upgrade. Hmmm.... come to think of it, I have an 8 puck RCS140 on hand. And thanks for the info on the heat shielding, that is certainly going to be useful for my plans ahead.

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Hey ZBomb, you know you drive a 996 when oil pressure is displayed on your video data 🤣. I watched some of your YouTube and I enjoyed it, thanks for sharing. If you run out of things to do to your car the Aasco flywheel, GT LSD and GT Daytona gear set is the bomb. Once you go to close ratios you never want to go back.

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Cool ! glad you like the videos, I have a long way to go as a driver / home mechanic but it has been pretty fun sharing it with people that are interested. I love the driving dynamics of the 996 - way more than I love the motor and the oil pressure thing has been a thorn in my side, especially after I spent what to me is a lot of money only to end up being the guy that displays oil pressure on his videos I can't say I haven't thought about switching to something else as the car and my desires have focused more on track work, but it is just so fun, easy and forgiving to drive I think I will continue to try to develop it. I have been thinking for a while the best way to go about a quicker car isn't dicking around with the motor trying to add HP, its improving the gearing to a more usable MPH range (I don't need over 155 I don't think) so it's cool to hear you say that. I have an OS Giken LSD in the car now but the LW FW / clutch setup and gearing are high on the list. Good luck next weekend man, I'll definitely be watching and cheering you on from the comments. You guys have got me really interested in trying to find a seat in an endurance car next year and give it a try, thanks for the inspiration.

Car and team are at Sebring. We start practice at noon tomorrow Chris

Looking forward to watching. Good luck gentlemen!

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Oh my...revised gearing would be utopia. I thought about it years ago and just couldn't pull the trigger. Cost was high. But as a buddy said to me a long time ago, "How fast do you want to go?"... It's certainly cheaper than an extra 100 HP. You got me thinking hard about it...

I will start a new thread in a few minutes. Chris