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Discussion Starter #1
I plan on going with a fidanza F/W and clutch setup.

Would the LS6 set-up be easier to install? i.e. no spacers & cutting, etc.

Is there really that much benefit to upgrade to the LS7 set-up?

Part numbers I am looking at are for the LS6

#198571 - F/W
#390563 - Four Point Three Clutch


Advise?
 

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2005 Cts-v
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I dont know what you have done to your ls6 and Im no expert, but from what i have researched you may want to find something a little heavier then that flywheel. That is a light ass flywheel for a heavy car, unless you plan on running at a track(not a dragstrip) i would think that might be just a bit too light. Our flywheel is heavy as sh*t, the ls7 fly wheel is likt 24lbs as i recall, UUC's is like 17-18lbs, and fidanza is like 14lbs. Like i said im no expert just imho
 

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escalade
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If you can wait a lil we will have a few of our clutchs in a few members ctsv to give some feedback.If you are set on the fedenza now i can help you get a great price.
 

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Discussion Starter #4
Car has no major modifications, and is simply in need of a new clutch, so I'd might as well upgrade.

Other than from a standing start, the lighter flywheel will not have any other negative affects, correct?
 

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Discussion Starter #5
If you can wait a lil we will have a few of our clutchs in a few members ctsv to give some feedback.If you are set on the fedenza now i can help you get a great price.
Unfortunately, I don't think I can wait much longer. I understand that the fidanza LS7 clutches come at a premium price to the LS6 clutches, and curious if it is worth it.

Also, would the fidanza LS6 set-up be an easier install?
 

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2005 Cts-v
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unless you love to chirp 2nd and 3rd, i dont think. Im not sure though, I really do like the light flywheels and want to do one myself, but Ive heard that for a even close to stock car that flywheel is just too light. However, like I always say opinions are like *******s, and maybe Ive just heard the wrong ones. I know stageup and a few others have the uuc flywheel and absolutely love it, thats what I would like to get one day.
 

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I am not so sure that a 14lb flywheel is "too light". Bear in mind that the flywheel and chrankshaft are coupled, which means you are reducing weight to the entire rotating assembly. Thus, changing from say a 26lb flywheel to a 14lb flywheel is not all that drastic of a percentage weight reduction of this rotating mass.
I once reduced the flywheel on a Yamaha V-Max from 12lb to 5.5lb. The crank weighed 26lb. It was a great mod.
If anyone out there is running a Fidanza 14lb please comment.
 

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2011 Black Diamond CTS-V
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highly recommend any lightweight flywheel, have the UUC 18lbs. and it rev's like quick fast and in a hurry like a bmw, i'm sure the 14lber would be even quicker, just know you won't use 6th gear anymore unless you're cruising around 70mph
 

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cts-v
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it seems every car forum has this same light flywheel issue where some people say that one is to light but another is ok. I know people who drag and road race on some very very light flywheel setups so i would be suprised to see it not work on our cars.


the other arguement that seems to come is is a light weight crank pulley/ alt/ ps etc
 

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05 CTS-V
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If you can wait a lil we will have a few of our clutchs in a few members ctsv to give some feedback.If you are set on the fedenza now i can help you get a great price.
what are you guys offeering?
 

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Im not saying its not, I was just giving him fair warning, from some of the criticism of a very light flywheel. I stated I was no expert on the matter, I just dont want him to put out money without at least hearing other opinions. I stated myself I would love to have a UUC flywheel, but I have heard people say that one is too light and I know the Fidanza is even lighter then that.
 

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Discussion Starter #12
Well I guess my flywheel question is answered. Any comments on the difference between the LS6 and LS7 clutch from Fidanza. I am assuming the LS6 replacement clutch would bolt right in as opposed to the modifications neccesary for the LS7 swap? Thoughts?
 

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04 CTS-V with a little hp persuasion device
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you will need a spacer or a longer slave either way you go. The LS6 and the LS7 are both single mass so they are both shorter than the stock.
 

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Discussion Starter #15
you will need a spacer or a longer slave either way you go. The LS6 and the LS7 are both single mass so they are both shorter than the stock.
So no easier installation oin either set-up. I guess my last question would be the difference between the LS6 and LS7 clutchs from Fidanza. Any real difference? OR just go with the LS6 becuase it would be cheaper?
 

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04 CTS-V with a little hp persuasion device
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If i did it again, I would do LS6 because of its cheaper initial cost and most aftermarket disk and pp fit the LS6 and are a couple hundred cheaper because its not a recessed surface like the LS7 flywheels.

I have the LS7 Fidanza aluminum flywheel (has recessed surface) and a stock LS7 disk and pressure plate as well as a stock LS7 slave. With the LS7 slave you dont need any spacers. With the stock slave you need a spacer that is .950" to install behind the slave. I came up with that number by measuring the stock flywheel and pressure plate bolted together and then the LS7 flywheel and pressure plate. That was the overall difference between the surface of the flywheel that touches the crank, to the fingers on the pressure plate. I do not know if the the LS6 single mass flywheel/clutch assembly is the same thickness as the LS7. If I had to guess, I would say yes it is, but its a guess. The only way to do it is buy one and measure them or call TPiS and ask them how thick the slave spacer is they sell. I asked around for a while and nobody could come up with an answer so I measured myself and had one made and used it for many miles before I finally installed the LS7 slave about 2 weeks ago. I only installed it because I thought mine failed and I had heard that the LS7 is stronger than the V's. The .950" spacer worked perfect and is the exact difference in the two flywheel/clutch assemblies.
 

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Discussion Starter #17
I have received my clutch and F/W finally:

Clutch: Fidanza #390563
F/W: Fidanza #198571

Do I need the a spacer for this set-up, if so where do I get it from. Thanks Guys.
 

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'05 CTS-V, '00 SLS, 98 SLS, 89 Eldo, '80 Eldo
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Doesn't Katech make the spacer?
 

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Platinum 2004 CTS-V
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Shouldn't Fidanza have the answer to that since it's their system?

Katech makes a spacer, but won't tell you the size. Plus...it's $90
http://katechengines.com/katech_inc/catalog/cts-v-slave-cylinder-spacer.htm

$90.10 -- For single-mass flywheel conversion
Purchase CTS-V Slave cylinder spacer

To eliminate the CTS-V's dual-mass flywheel
For 2005-2008 CTS-V LS6/LS2
Designed to work with GM clutches, but may be used with aftermarket clutches although not guaranteed.


When Nmaier measured his LS7 flywheel and I measured LS6 fw, they were almost an inch difference from each other (since LS6 is flat, and LS7 is raised)

ctsv154.....maybe we should get into the spacer making business!? Ha
 
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