What did you do to your 996TT today?
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Thank you. I searched to try and find what brand these might be but don't see this triangular slotted pattern on anything available now. They are probably from 2012 timeframe looking at service records. No P/N on the work order.
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997GT3 front rotors are the wrong offset to use with AWD carriers. There rears are the same as TT. Cayenne rotors have GT3 offset but weight an absolute ton. I would never recommend those.
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Incidentally, the increased smoothness of the engine also seems to largely negate the gearbox LWFW rattle that is very prevalent on a Turbo Mezger, much more so than a GT3/Cup Mezger. Even with my featherweight 5.5" carbon clutch, the gearbox rattle is minimal. Don't know if you've noticed that too with your set up.
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Cervelli and I discussed this a while back and it seems the whole "Mezger rattle" is largely caused by harmonics of the heavier Turbo crankshaft and bolted IMS. When you replace these parts with the lighter GT3 dual oiled crank and the billet one piece IMS, the "bolts in a can" rattle essentially disappears. The fact that all the 106mm Mahle Motorsport pistons are all within 1g of each other contributes to the overall smoothness of the engine. It's a sum of all parts that completely change the character of the engine.
Incidentally, the increased smoothness of the engine also seems to largely negate the gearbox LWFW rattle that is very prevalent on a Turbo Mezger, much more so than a GT3/Cup Mezger. Even with my featherweight 5.5" carbon clutch, the gearbox rattle is minimal. Don't know if you've noticed that too with your set up.
Incidentally, the increased smoothness of the engine also seems to largely negate the gearbox LWFW rattle that is very prevalent on a Turbo Mezger, much more so than a GT3/Cup Mezger. Even with my featherweight 5.5" carbon clutch, the gearbox rattle is minimal. Don't know if you've noticed that too with your set up.
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17ram2500 (03-24-2024)
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I have a spare 6TT crankshaft. I was thinking that having it balanced to tight tolerances might help the rattle? I don't see a gt3 crank in my budget.
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Cervelli and I discussed this a while back and it seems the whole "Mezger rattle" is largely caused by harmonics of the heavier Turbo crankshaft and bolted IMS. When you replace these parts with the lighter GT3 dual oiled crank and the billet one piece IMS, the "bolts in a can" rattle essentially disappears. The fact that all the 106mm Mahle Motorsport pistons are all within 1g of each other contributes to the overall smoothness of the engine. It's a sum of all parts that completely change the character of the engine.
Incidentally, the increased smoothness of the engine also seems to largely negate the gearbox LWFW rattle that is very prevalent on a Turbo Mezger, much more so than a GT3/Cup Mezger. Even with my featherweight 5.5" carbon clutch, the gearbox rattle is minimal. Don't know if you've noticed that too with your set up.
Incidentally, the increased smoothness of the engine also seems to largely negate the gearbox LWFW rattle that is very prevalent on a Turbo Mezger, much more so than a GT3/Cup Mezger. Even with my featherweight 5.5" carbon clutch, the gearbox rattle is minimal. Don't know if you've noticed that too with your set up.
Actually I did notice the lwfw rattle is all but eliminated and lot of the vibrations from the solid mounts seemed reduced but wasn't sure if it was in my head, haha. Everything was just smoother and crisper, and I'm completely untuned still which is all the more impressive to me.
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pretty sure the rattle is the crank and not the IMS...I have a 991Cup IMS but stock crank, still have the rattle, just did a Cup/4.0 F.W. on a 7.1gt3 and very little gearbox rattle...really doesn't matter either way
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When I ran it the other day for half an hour and listened to it after winter hibernation, the slight rattle sounded lovely. I am very disappointed it's going to rain this weekend.
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The lwfw rattle sets off my tinitus big time, giving me vertigo. I used the lwfw setup for 300 miles and had to get rid of it. While I loved the zingyness of the setup I couldn't handle the noise.
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Majority of it is the crank as far as I can tell. My first 3.8 build did the GT3 crank but retained the TT IMS. It was a huge improvement. The nest build used both the GT3 crank and IMS and it was even better.
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I wouldn't be. Some engines may have the chain tensioner set tighter than others. Mine is not audible until it warms up and it even has 5W-50 in it. I think it's an odd noise for an engine but the nature of the beast, for most that is.