Bxstr

Here's some additional info on the topic:
http://performancedevelopments.com/p...enginefailure/
https://rennlist.com/forums/997-gt2-...l#post11525767
https://rennlist.com/forums/997-gt2-...sequences.html
https://rennlist.com/forums/997-gt2-...ml#post7567136
https://rennlist.com/forums/997-gt2-...cking-out.html
https://rennlist.com/forums/997-gt2-...l#post12136072

Ultimately, it seems to be an issue on both .1 and .2, but more of an issue on the .2. I know one member in particular on here had a .1RS that had the bolts back out on him.
TPC racing has a fix. Sharkwerks has a fix. I know Sharkwerks, understandably so, has not disclosed how they fix the issue. The easiest solution seems to be the dampener from Dundon.

I go back and forth about what I'll do when I need to replace my clutch. The LWFW seems to be a great mod, but I also appreciate the reliability of the stock DMFW. I haven't driven a GT3 with the LWFW, although the 992 GT3 I drove was a bit tricky initially (stalled it twice) with how light the flywheel was. So not sure if the LWFW would be easier or harder to drive. Probably neither, would just take some seat time to get used to it.

If I had a shop like Sharkwerks that had a fix that was permanent and proven, I'd just do that with the LWFW, but I'd likely be stuck with using the Dampener instead since I'm not sure any of the local shops have experience with the other methods.

Brian Himmelman

if that is correct then my 997.1 RS with single mass flywheel should be balanced to engine and the slightly lighter 4.0 clutch and flywheel kit should be ok as opposed to the GT3’s that are balanced to the dual mass … anyone add?

RAudi Driver

I wonder how the damper affects the smfw characteristics?

Bxstr

Both the 997.1 GT3 and GT3RS use the M9776 motor to my knowledge. So wouldn't the engine have been assembled with no knowledge of which car it was going to go into? Even the gearbox is the same, the G9790. My thought is that there is no difference outside of one having a LWFW installed and the other not. My guess is Porsche simply was trying to get out of liability if an engine failed by releasing the bulletin. But that is all speculation.

Bxstr

Conflicting reports on how it affects characteristics of motor.

Some say not at all:
https://rennlist.com/forums/997-gt2-...l#post17210498
https://rennlist.com/forums/997-gt2-...l#post18671597

Some say it does:
https://rennlist.com/forums/997-gt2-...l#post17163546

RAudi Driver

Thanks those links are a good read.

powdrhound

The whole damper thing is way overplayed in my opinion and pretty much a Rennlist thing. None of the Europeans like Manthey or others do it when adding the LWFW set up. The factory RS doesn't have a damper and the engine and gearbox is identical. Drive the damn car and enjoy the hell out of it. If it breaks, fix it.... Just my $0.02...

Jrtaylor9

I can still remember my first 7-3rs drive to this day years ago. Goose bumps and love at first drive.

vma1788

OR, hear me out, if you don't drive it you don't need to worry about the damper. AND you'll get rich from keeping the miles off.

powdrhound

Where’s the fun in that?

Wonderdan

that’s most RS owners… lol, I for one wouldn’t be heartbroken if something “forced” me to do a 4.1

nle

My dream car when new. Listened to a bunch of yahoos on the internet (thx 997 gt2/gt3 subforum) and bought my RS without ever sitting in or driving one when it was within reach. Can confirm it was one of the best decisions I’ve ever made.

RapidGT

I personally like the chatter of the LWFW. Makes the car sound more mechanical. The thing about the LWFW I find not great especially in normal driving is that there is no rev hang and the engine loses revs quickly. Have to shift faster than you would in a GT3 with a dual-mass flywheel so the revs don’t drop below the range they would be at in the next gear which makes up shifts jerky. Having to do quicker shifts with the quite heavy clutch and shifter can be tiring. Don’t get me wrong I still love the LWFW as it makes a world of difference in spirited driving, but in normal driving it can wear me out.

blaksquirrel

Sorry to add to the thread hijack haha - I agree with all of this, but at this point I am very used to the LWFW setup on my 997.1 GT3. I have probably done at least 40k with it, and if I'm driving slow I will do a little blip rather than hurry every shift.

Most importantly - I originally did the LWFW without doing a different pulley and the crankshaft bolt DID back out after about 10k miles. Luckily I turned the car off immediately (the dash list up when the belt came off) and there was no damage. I did a Dundon dampener and haven't had any further issues. (The 997.1 RS does use a different pulley, it has holes in it rather than the solid disc on the regular GT3.) I would recommend either the RS pulley or the Dundon part for peace of mind with this conversion.

Steve Theodore

Blip before shift indeed, whether it's up or down (in the case of LWFW equipped cars).