RS 3.89 R&P and 6th gear conversion..
#16
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Robocop305 (02-24-2023)
#17
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https://rennlist.com/forums/997-gt2-...l#post14834787
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Chris Cervelli at Cervelli Technical Service (CTS). He's in Denver, does not advertise, pretty much all word of mouth. I've known Chris for many years and he's one of the finest engine and gearbox builders in the business. He's done all my engine and gearbox builds for the last 10 years. He's also a Motec dealer / tuner. Pretty multi faceted guy and fairly picky on what projects he takes on.
Last edited by powdrhound; 12-17-2022 at 01:28 PM.
#20
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The damper is quite heavy and it kinda defeat the purpose of the LWFW. I had my cam actuators modified and install larger bolts like in the link below to combat the potential issue. (post #770)
https://rennlist.com/forums/997-gt2-...l#post14834787
https://rennlist.com/forums/997-gt2-...l#post14834787
#21
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The damper is quite heavy and it kinda defeat the purpose of the LWFW. I had my cam actuators modified and install larger bolts like in the link below to combat the potential issue. (post #770)
https://rennlist.com/forums/997-gt2-...l#post14834787
https://rennlist.com/forums/997-gt2-...l#post14834787
Last edited by Auto_Werks 3.6; 12-16-2022 at 04:20 PM.
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f50nut (12-17-2022)
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3.89 R&P was $3100 and the 6th gear was $800, direct from Porsche this past April. Out the door a few Lattes over $4K, probably a bit more now with inflation factored in. Makes sense to do the Guard clutch pack at the same time to replace the weak OEM pack. The Guard clutches are about $900 direct from Matt at Guard.
#23
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The damper does have some weight to it, but it certainly does not defeat the purpose of a LWFW. There is a reason flywheels aren't the size of a crankshaft pulley, and that's because the moment of rotational inertia is the critical attribute, not the mass. For something the size of a harmonic balancer to store energy like a flyheel it would have to be several orders of magnitude heaver. This is something to watch when buying a lightweight flywheel... The more mass is removed from the outer ring, the more successful the outcome. If the mass was all removed from the center hub, even a fairly significant weight reducion won't be noticed in the way the enigne revs.
https://www.youtube.com/watch?v=CHQOctEvtTY
https://www.youtube.com/watch?v=CHQOctEvtTY
So if the peace of mind is more important to you than the damper will be a good choice.
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Robocop305 (02-24-2023)
#24
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You are correct but by installing the damper the car will rev less lively compared with just the LWFW. This is confirmed by my mechanic who has installed many of them and reports form owners that have the damper.
So if the peace of mind is more important to you than the damper will be a good choice.
So if the peace of mind is more important to you than the damper will be a good choice.
#25
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The damper does have some weight to it, but it certainly does not defeat the purpose of a LWFW. There is a reason flywheels aren't the size of a crankshaft pulley, and that's because the moment of rotational inertia is the critical attribute, not the mass. For something the size of a harmonic balancer to store energy like a flyheel it would have to be several orders of magnitude heaver. This is something to watch when buying a lightweight flywheel... The more mass is removed from the outer ring, the more successful the outcome. If the mass was all removed from the center hub, even a fairly significant weight reducion won't be noticed in the way the enigne revs.
![](https://cimg4.ibsrv.net/gimg/rennlist.com-vbulletin/2000x1504/006745be_addd_403c_82ee_f3d5061cf827_9ff04163fe21d820a9b8be21c25962c37ab163df.jpeg)
Last edited by powdrhound; 12-17-2022 at 04:37 AM.
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Robocop305 (02-24-2023)
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Picked up the car today and did a quick test drive. Everything turned out perfect. THIS IS HOW THE CAR SHOULD HAVE BEEN GEARED FROM THE FACTORY! The ratios are spot on for this engine and the tall 6th is nice to have if you are cruising at 80mph or so on the freeway. The engine is really smooth throughout above 3K or so and with the shorter gearing is much more eager to go. I'm actually going to wanna drive the car now and hopefully put more miles on it than 20 miles I did this year. Thanks again to Chris at CTS for making the swap for me... Now I just need to dig out the center muffler delete I've had sitting in the box since last year and install it along with the E07s.
Last edited by powdrhound; 12-20-2022 at 01:49 AM.
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Picked up the car today and did a quick test drive. Everything turned out perfect. THIS IS HOW THE CAR SHOULD HAVE BEEN GEARED FROM THE FACTORY! The ratios are spot on for this engine and the tall 6th is nice to have if you are cruising at 80mph or so on the freeway. The engine is really smooth throughout above 3K or so and with the shorter gearing is much more eager to go. I'm actually going to wanna drive the car now and hopefully put more miles on it than 20 miles I did this year. Thanks again to Chris at CTS for making the swap for me... Now I just need to dig out the center muffler delete I've had sitting in the box since last year and install it along with the E07s.
#29
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Thanks Scott! For me, in conjunction with the 4.0 clutch/LWFW set up this mod makes for a perfect 7.2GT3 with RS drivetrain. For a street use car I really like the understated "fly under the radar" clean look of the narrow body 7.2 vs. the "boy racer" look of the RS with the big stickers and the large wing with the aluminum uprights. Power wise the car still feels rather soft compared to my track 996 but for the street it's perfect, lively and makes all the right noises. Thumbs up for sure!
Last edited by powdrhound; 12-21-2022 at 08:32 PM.
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point2point (12-22-2022)
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I did this exact change on my 997.1 RS. I also did the Guard internals while in there, and fixed the problematic second-gear detent issue. It transformed the car.
Last edited by HarmonyJim; 02-24-2023 at 01:51 PM.
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Brian Himmelman (04-09-2023)