Driving impressions w/LS7 clutch swap?
Cadillac
 

Cadillac Forums | Help Us Help You | Advertise | Cadillac Parts | Cadillac News | Cadillac Classifieds / (Old System)

Cadillac Technical Archive | Cadillac Dealers | Cadillac Reviews | Cadillac Dealer Reviews | Cadillac Vendors

CadillacForums.com is the premier Cadillac Forum on the internet. Registered Users do not see the above ads.
+ Reply to Thread
Page 1 of 2 1 2 LastLast
Results 1 to 15 of 22
Like Tree3Likes
2004-2007 Cadillac CTS-V Performance Mods Discussion, Driving impressions w/LS7 clutch swap? in Cadillac CTS-V Series Forum - 2004 - 2007; I've read up on the LS7 clutch swap for my 2005 CTS-V and plan to have my mechanic do the ...
  1. #1
    Derek5.7 is offline Cadillac Owners Member
    Automobile(s): 2005 Cadillac CTS-V
    Join Date
    Apr 2013
    Posts
    61

    Driving impressions w/LS7 clutch swap?

    I've read up on the LS7 clutch swap for my 2005 CTS-V and plan to have my mechanic do the swap so this is NOT a "how to" question but more a "what's it like" question?

    I'd love to hear all driving impressions but I'm also interested in hearing from guys in a similar car to me which has mild mods (high flow cats, CAI, etc. NOT racing cams/blowers, etc.) and who have the STOCK LS7 clutch and flywheel combo.

    Is the classic "parade driving" clunk completely eliminated?

    Does it still have a stock feel when driving/shifting?

    Does the torque and HP come in earlier now that some of the flywheel weight has been shed?

    Is the quicker drop in revs between shifts problematic or close to stock?

    Any thoughts/impressions are most welcome.

    Thanks.

  2. Remove Advertisements
    CadillacForums.com
    Advertisements
     

  3. #2
    JFensty's Avatar
    JFensty is offline Cadillac Owners Enthusiast
    Automobile(s): 04 Blk Cts-V
    Join Date
    Oct 2010
    Location
    Allentown PA
    Age
    37
    Posts
    594
    The parade clunk will not be fully eliminated unless you go to an 8.8 or 9" rear. That said, I have close to 60k on my ls7 with most of those miles being spirited driving. Lt's, high flow cats, small cam, etc. Revs faster for better revmatch shifting and rpms do not tend to hang on decel. Better driving experience overall.

    Sent from AutoGuide.com Free App

  4. #3
    OneFast V is offline Cadillac Owners Enthusiast
    Automobile(s): 2005 Raven Black CTS-V
    Join Date
    Mar 2010
    Location
    San Jose, CA
    Age
    27
    Posts
    980

    Re: Driving impressions w/LS7 clutch swap?

    Parade clunk is a combination of diff bushing, 2 piece driveshaft and dual mass flywheel. So if you have CS/RS rear diff bushing and the LS7 clutch+FW you are going to eliminate most of the parade clunk. the last bit would be switching to a 1 piece DS. The LS7 clutch + FW drive basically similar to stock in terms of pedal effort and clutch engagement.

  5. #4
    Naf's Avatar
    Naf
    Naf is offline Cadillac Owners Connoisseur
    Join Date
    Apr 2007
    Posts
    2,089
    If u get the diff bushin, ls7 clutch and revshift shaft union then yes the clunk is gone. The less rubber u have in your drivetrain then the less clunk u will have...

  6. #5
    rand49er's Avatar
    rand49er is offline Cadillac Owners 10000+ Posts
    Automobile(s): 2005 CTS-V, 2011 Cruze 1.4T 6MT
    Join Date
    Jan 2005
    Location
    South Lyon, MI
    Age
    65
    Posts
    13,313

    Re: Driving impressions w/LS7 clutch swap?

    Eliminating the dual-mass FW, the stock clutch, the OEM axles, and replacing with diff bushing does not get rid of the clunk.

    You need to do the diff as JFensty says. For some reason (not sure I've ever read exactly why), GM spec'd in a bunch of lash in the diff gears.
    '05 CTS-V, Maggie, Kooks, Hotchkis, Ground Control, Corsa, B&M, DSS/Hendrix, Full 3M Clear Bra, Autovation, V Headrests, CTS Console, STS-V 55w Fogs, Black Vette FRCs, Specter Werkes, Katech LS9 Clutch, SS Brake Lines, Heavymetals U-Turn Fuel Line Eliminator, Momo Combat Evo Shift Knob, Wldwhl Clear Sidemarkers, Linea Corse LC855 Wheels or OEM wheels w/'06-'07 Center Caps, plus a couple more. 472 RWHP/411 RWTQ (Mustang Dyno).

  7. #6
    pato is offline Cadillac Owners Fanatic
    Automobile(s): 2011 CTS-V
    Join Date
    Aug 2011
    Posts
    188
    ^^^ Yea that!
    Diff still has a lot of play (lash) after diff bushing, stock clutch, and motor/trans mount replacement.

  8. #7
    Lou72 is offline Cadillac Owners Member
    Automobile(s): 2004 CTS-V
    Join Date
    Oct 2011
    Location
    Central Jersey
    Age
    20
    Posts
    46

    Re: Driving impressions w/LS7 clutch swap?

    I didn't see much of an improvement as far as clunking goes on my nearly stock car. Good motor mounts, trans mount, and diff bushing are all much better at eliminating clunk. Performance wise, there is very little to no change in the power band as far as I can tell.

    Casual driving does have minor changes, but all for the better in my book. The engine does change revs noticeably quicker, especially at slower engine speeds. I always thought that the stock flywheel required a lot of waiting between shifts in order to get a good rev match. And if a shift is poorly matched, you don't lurch nearly as much as with the heavy stock flywheel. I was afraid that my days of simply working the clutch to get around at parking lot speeds were over, but it hasn't been a problem. The engine is only slightly more prone to stall with the light flywheel, but not enough to be an issue. Driving in stop and go traffic is no worse than with the heavy stock flywheel.

  9. #8
    carlson_mn is offline Cadillac Owners Enthusiast
    Automobile(s): Platinum 06 CTS-V, kooks, magnaflow
    Join Date
    Jul 2012
    Location
    MN
    Age
    32
    Posts
    634

    Re: Driving impressions w/LS7 clutch swap?

    Good. I'm in stop-n-go rush hour everyday for about 15-20 minutes and I really enjoy just letting it sit in 1-3rd gears and it coasts along just fine on its own nice and smooth.

    I had heard one or two people reported loss of mpg with a lighter flywheel.

  10. #9
    FuzzyLogic is offline Banned
    Join Date
    Mar 2011
    Posts
    2,048

    Re: Driving impressions w/LS7 clutch swap?

    Quote Originally Posted by carlson_mn View Post
    I had heard one or two people reported loss of mpg with a lighter flywheel.
    There's no logical explanation for that.

  11. #10
    VincentT is offline Cadillac Owners Member
    Automobile(s): 2004 CTS-V
    Join Date
    Oct 2012
    Posts
    50

    Re: Driving impressions w/LS7 clutch swap?

    To be honest, I don't know what driving with the stock flywheel is like. I can compare the LS7 with a Monster stage II though, and I like the LS7 better. The LS7 setup works really well in my experience. As the other guys noted, clunk is still there. The clutch was designed as a stock clutch, so it has a good feel and works rather well.

    Quote Originally Posted by FuzzyLogic View Post
    There's no logical explanation for that.
    At least not other than driving style changes after the swap.

  12. #11
    carlson_mn is offline Cadillac Owners Enthusiast
    Automobile(s): Platinum 06 CTS-V, kooks, magnaflow
    Join Date
    Jul 2012
    Location
    MN
    Age
    32
    Posts
    634

    Re: Driving impressions w/LS7 clutch swap?

    They said their mpg dropped on some highway trips through hilly areas, like it didn't hold momentum getting up the hills as well. Didn't make much sense to me either.

  13. #12
    darkman's Avatar
    darkman is offline Cadillac Owners Master
    Automobile(s): 2005 CTS-V
    Join Date
    Nov 2005
    Location
    Spring, Texas
    Posts
    7,075

    Re: Driving impressions w/LS7 clutch swap?

    Quote Originally Posted by carlson_mn View Post
    They said their mpg dropped on some highway trips through hilly areas, like it didn't hold momentum getting up the hills as well. Didn't make much sense to me either.
    My highway mileage improved (insignificantly) with a lighter flywheel. The change in flywheel weight is inconsequential at highway speeds during which all of the rotating weight of the entire car provides "flywheel effect."
    carlson_mn likes this.

  14. #13
    FuzzyLogic is offline Banned
    Join Date
    Mar 2011
    Posts
    2,048

    Re: Driving impressions w/LS7 clutch swap?

    Quote Originally Posted by carlson_mn View Post
    They said their mpg dropped on some highway trips through hilly areas, like it didn't hold momentum getting up the hills as well. Didn't make much sense to me either.
    Interesting logic. What they described is highly unlikely, since they would have burned more fuel overcoming that inertia to get up to speed in the first place. Lighter is always more economical, for a given, commanded rate of acceleration. Under steady state operation, rotating inertia has no effect. For parts that experience more of a linear acceleration (e.g. rocker arms), the mass (and resultant inertia) of the component is always at play, generating losses.
    carlson_mn likes this.

  15. #14
    silver1r is offline Cadillac Owners Member
    Automobile(s): 2004 CTS-V
    Join Date
    Jan 2013
    Age
    28
    Posts
    12

    Re: Driving impressions w/LS7 clutch swap?

    You might notice that for the 1st 500 miles the engagement for the ls7 is right off the floor. After some miles it will come up to about stock. The biggest improvements for me were much better clamping force, and it got rid of the diesel feel when I shut off the engine that makes it sound like a pos.
    carlson_mn likes this.

  16. #15
    Becker's Avatar
    Becker is offline Cadillac Owners Fanatic
    Automobile(s): 2006 black with tan V
    Join Date
    May 2013
    Age
    28
    Posts
    375

    Re: Driving impressions w/LS7 clutch swap?

    I am about to order an LS7 from Scoggin Dickey and can not decide on the stock flywheel (ls7) or the RAM 19lb aluminum.

    I daily drive mine about 10 miles each way, and drive quite a bit on my days off. Just wondering if anybody has any insight on this?

    I will also be ordering a powertorque ls7 slave and remote bleeder from tick, and some new bolts.

Quick Reply Quick Reply

Register Now

Please enter the name by which you would like to log-in and be known on this site.
If you do not want to register, fill this field only and the name will be used as user name for your post.

Please enter a password for your user account. Note that passwords are case-sensitive.

Please enter a valid email address for yourself.

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Bookmarks

Cadillac Posting Rules

  • You may post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts
Read about Lincoln | Buick | Kia Forte Forum
Need products for your Cadillac? Check out your options at the links below:

custom floor mats | Cadillac Chrome and Black Chrome Wheels | window tinting