This is what I was thinking Still for sale, this is truly a great upgrade and at half price you can't go wrong.

 

The dealer told you that a LWFW would result in a cracked engine case? I assume it was Pepe Porsche in White Plains who told you that.

While I am sure that Pepe has your best interests in mind, that statement has no basis in fact. It's actually kind of bizarre. I love my Hennessy Porsche Service guys, and so am inclined to avoid being cynical, however, perhaps Pepe would rather sell you their Porsche OEM dual-mass flywheel than install the aftermarket Aasco LWFW you already have on hand?

What was their explanation around their assertion? I'd love to understand where they came up with that.
CATTMAN

 

Dude, you are 100% right. Yes the car is at Pepe Motors and they are trying to sell me a FW from a GT3 RS. Also, he is trying to sell me an exhaust. Well I am thinking about getting your mufflers if they are still for sale. Anyway, he was telling me stuff that it will not be balanced right and cause vibration.

 

Wow.
That's too bad.
But here's the deal: the Aasco LWFW won't crack anything. I'd heard these assertions previously, and they are based on a fear that the added harmonic vibration from a single-mass FW could damage the driveshaft. I do not believe it's a valid concern whatsoever. I am about to install an SC with my LWFW, and have run everything from bypass pipes to AH mufflers, and AWE cats- no problems, ever, on my DD with over 46k miles.

What is true is that the OEM 997 dual-mass flywheel does reduce driveshaft vibration. Thus, an Aasco LWFW means more driveshaft vibration. Enough to crack anything? That's taking it waaaay too far.

The reality is that a LWFW, while a terrific performance upgrade, does add what I'd describe as a subtle "clatter" sound at idle. If you've ever played Backgammon, you know the sound of shaking the dice in the sleeve? It reminds me of that, at idle.

This begs the question: why does Porsche put a LWFW in the RS, but not the base 997? Well, if you know why they offer (or used to offer) radio delete, sunroof delete, etc. on their performance models, then you know the answer.

Sorry about Pepe. You might want to confer with another local dealer about installing your new engine, too. There are some excellent Porsche service depts in the tri-state area. I can get you an insider referral if you want/ need, along with a call-ahead so they know you're coming.
CATTMAN

 

I woild stick with the OEM clutch . The car is an 05 with a new motor and whatever you put into it now you will never see upon exit . PLUS -- the OEM clutch is magnificent on the 997S , completely free of chatter , or engagement concerns . Why mess with it at all? Get the free motor and call it a day.

 

If they will install it at the same time, I say go for it. If your OEM clutch has a reasonable amount of life left on it, you can keep it and be fine!

As for the cracking, I think they are referring to Harmonic Vibration, this is a problem with GT3's adding an RS Flywheel, without modifying the pulley. There are risks to any mod, but this one has a pretty safe record on the Carrera's

 

A clutch has nothing to do with chatter- it's the LWFW that adds chatter. And a Stage 2 clutch has no engagement concerns.

However, if your original clutch is in good shape, there is no reason to change it.

That said, adding a LWFW is one of the best performance mods you can make to a naturally-aspirated 997. I've done just about every non-FI (forced induction) mod available, and can tell you that most of them amount to a hill of beans. The LWFW, however, quite logically, increases net RWHP by reducing parasitic drag in the drivetrain.

If you have the LWFW in hand, have them put it in. As for the clutch, assuming it's a Sachs Stage 2, you can take it or leave it. If labor is free, and you already have the parts, go for it.
CATTMAN

 

+1, this the most accurate statements that I have read on this forum today! Most of the mods I have are insignificant compared to the LWFW, and wouldn't hesitate to do it again! Very good advice John!

 

Thank you, sir.
Just trying to share real-world experience in the hopes that it will triumph over heresy.
CATTMAN

PS Who is "John Galt"?

 

1) I am not familiar with the sachs stage 2 clutch but I am familiar with the kevlar stage 3 in my Evt700 and believe me engagement is an issue . In fact a forum member in New Zealand was fearing rolling off a mountan when he first got his car with it . I mastered it with time but went an extra step to convert it to a NON pwer assist Gt2 conversion .

In short --changing the clutch DID make change . Now if you are saying that with the normally aspirated car the change is positive then that's great but I would have to drive one to know for sure.

2) The flywheel sounds great but I don't see the sense to it in a 2005 car with a new motor . If he faces an issue with that motor then they have every exit they need to deny any accountability if they are telling him that it could cause engine problems --EVEN if they are wrong . They will still put it in writing and if that new motor faces an issue he faces this dilema .

3) Lets say the car works great --the best case scenario . The motor is good , the clutch is good, the flywheel is good and they are all happy -- he will still never see a dime of this in a five year old car . Perhaps my reasoning differs . I like to have all my mods in the begiining so that the entire time I have the car it's maintained at what i feel is peak . If I had a 5 year old car I woild not put a cent into it . I'd save that money for the next car . That's just my own bias but it is grounded in cost savings related to the timeline of ownership.

 

Larry,
I love you man. But I have to counter your pts one at a time, out of respect:

1.) I have seen, felt, and tinkered with Sachs Stages 1, 2, and 3. I am choosing to let my real-world experience dictate each word I write. Not sure who your friend on a mountain is (or was), but I am talking about the Sachs Stage 2. If you want to debate the Stage 3's drivability on a TT, I am under-prepared. I am only providing honest and real content around a 997 NA with a Stage 2. BTW, just take a look at each unit, and you will see that while there is a clearly discernible difference between Stages 1 & 2, there is a sea-change delta from Stage 2 to 3.

2.) Not seeing the sense in a mod is personal. Does a LWFW make a performance difference: yes, and there's not much debate about that. Is it worth it on a new car, used car, old car, whatever car- that's to be decided by the owner, but if labor is nil, and the parts are already in hand, then the only fear is deniability of warrantee? Come on, if that's your best argument, then don't change your turn signals.

3.) Your economics arguments here are well known, and I respect them. I watch all your posts on "time to buy" or "time to sell", and you make well-reasoned pts. However, none of those account for why you have decided to create a 700+hp 997TT. That was your choice, right? I am sure you had an economic decision behind it which informed your investment, but at the end of the day, you did what you felt was best for more than just your wallet- if investment (without joy) were the only consideration you'd sell your Porsche and your M3, and drive your Honda all the time, and have a Camry as a backup.

Look, I'm a fan, so I hate to argue here. I'm tired, and have had a couple glasses of Chianti, so I may be off base. Feel free to let know. Hopefully, I've been a gentlemen in my counter-points, and maintain your respect despite my politely stated disagreement.
In kindness,
CATTMAN

 

I will reply where I agree and disagree and state why -

1) You are correct in saying that I don't know the sachs clutches . The stage 3 kevlar clutches used on Turbos with high Hp may be very different BUT the OEM 997S clutch is as close to perfect as i can imagine .Why mess with it at all and risk even the slim possibility of any negative emanating from the change? How much better can it be ?

2) Again you are right that whether to do the mod or not is opinion. But look at the thread title . He's asking for an opinion . It's not just an issue of warranty . They are putting a new motor in his car and with that comes the potential that things may not be perfect. After all one does see a lot of "new motor" cars on independent lots and there are posts on this forum by guys who got new motors and things may not work out . ANY change will give them a good reason to deflect accountability and deny a repair ESPECIALLY when they are giving him the heads up . And I may even agree with you that they are wrong but neither you or I will be the one to fix his new engine if something comes up . They will and he needs them in his corner unless he wants to spend even more money on his 05 car.

3) My Turbo is not a rational purchase so again I agree with you --BUT I didn't wait 5 years to start modding it and picking the time when its broken to do it . I began early so that i could enjoy every moment of it .

Lastly -- when a car breaks it has to be repaired . On a major warranty repair like Porsche giving him a new motor even though it may sound cost efficient in terms of labor hours I do not feel it is a step in the right direction to fuse a repair with adding aftermarket mods .

 

Thank you all for your input. I think I am leaning toward not doing it. I am getting push back from the Pepe. They will not cover the engine for the two years if I install these parts. Also, they do not have the tools to reprogram the DME with the new FW, so I don't want to be pulling out and have the car stall on me every time I stop. So if anyone is interested I will be selling the clutch kit and the LWFW that I have still brand new in the box. I will post a new thread with the parts numbers and some pictures. PM me if you are interested. Thank you all this has been very helpful!!!

 

I would have them install the engine, and then get a third party to install the clutch and LWFW after the fact. If there ever is a problem you can pull the LWFW and reinstall yours so they can't pointing the finger at something that will allow them to walk away.

There is no reprogramming required, the engine will be fine without the OEM programming and will not stall. The stall issues would go hand in hand with pre 996 LWFW mods, and the electronics on the modern Porsche's will adjust to the different rotation.

Just my 2 cents, it is your call.

 

if you plan on keeping your car (and you should) then you will need to replace clutch in the future. I would not sell those parts as you will need them anyway.