RATTLE Snake Bite the XLR-V - Page 10
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 10 of 10 FirstFirst 1 2 3 4 5 6 7 8 9 10
Results 136 to 143 of 143
Like Tree2Likes
Cadillac XLR-V Series Forum Discussion, RATTLE Snake Bite the XLR-V in Cadillac V-Series Forums; Lets try again http://www.hotrod.com/pitstop/hrdp_1...n/viewall.html...
  1. #136
    deadringer's Avatar
    deadringer is offline Cadillac Owners Fanatic
    Automobile(s): Modified 06 XLR-V
    Join Date
    Jul 2004
    Location
    Houston, TX
    Posts
    152

    Re: RATTLE Snake Bite the XLR-V

    Lets try again

    http://www.hotrod.com/pitstop/hrdp_1...n/viewall.html

  2. #137
    GizmoQ's Avatar
    GizmoQ is offline The Last Good Gremlin
    Automobile(s): 06 XLR-V and 96 Eldorado ESC-V -- One day ;)
    Join Date
    Mar 2007
    Location
    St Louis, MO
    Posts
    2,631

    Re: RATTLE Snake Bite the XLR-V

    Quote Originally Posted by deadringer View Post
    I wonder if you're maybe leaving lots of power on the table that you're not getting... according to this article:

    http://www.hotrod.com/pitstop/hrdp_1...n/viewall.html

    The northstar engines can hit a 8500rpm redline with just a simple valve spring change... and these guys at Cadillac Hot Rod Fabricators seem to know what they're doing - perhaps you should give them a call and see what your LC3 motor can really do... most of the tuners I've spoken with seem to be LS tuners who just are using the same tricks on the Northstar, whereas CHRF looks like they specialize in Northstar.

    http://www.chrfab.com/

    Thoughts?
    Quote Originally Posted by deadringer View Post
    I talked to CHRFab several times over the years when I was working on the motor of my Eldorado to reach "V" status. The article makes it sound simple, bolt-on parts and go, but its not. Everyone knows and they (CHRFab) readily admit it, too, that its easy to get high HP out of a NorthStar - just not in a Cadillac. No one has figured out how to manage a built NorthStar with the Cadillac computers. From what I remember, 600+ is about all you can manage with the Cadillac PCM and that was drastically and later fatally modified PCM and engine. I'm sure the technology is available now, to go bigger and better. All it costs is time and money - neither of which I wish to invest to the degree necessary.

    Since I'm only looking for 550-575RWHP, I decided to see if I could get there without NOS or changes to the internals. NOS would cost me what little trunk space there is with the top down. I have a list of what I'd need done should I have to rebuild the motor (I'll add the CHRFab springs tonight) and the total cost for the entire overhaul is somewhere around $8.5K and three months with no guarantee the PCM can tame it. I'm pretty close to my goal now and its been much, much cheaper than a purpose-built motor. My PCM reprogramming is currently adequate, but I know there are a couple parameters I need to expand further.

    Lastly, over the 500-550TQ threshold, the tranny becomes the weak link. And above 550TQ, its a toss-up between the tranny and the rear end. Modding them to take that kind of abuse is in the $3500-6500 range; again with no guarantee the Cadillac computers will cooperate with the changes.

    ELWOOD has always been an experiment to see if I can surpass the base Z06 in power without removing the motor or tranny, i.e., original internals and bolt on adders sans NOS. It had to maintain the same ride and comfort, cockpit and trunk space, and match the Z06 in gas mileage.
    Snake Bit Super Chilled Black Raven 2006 Cadillac XLR-V aka Elwood (Jake's brother)
    Verified 501rwhp and 486TQ at 6000RPM so far...final goal 575/550

    ELWOOD - "Corvette in a Tuxedo ... with a Jet Pack"



    2013 St Louis Region SCCA Solo SSM Class Champion
    Texas Mile Record Holder: Street Legal XLR @ 159.5MPH
    ECTA LSR Record Holder: 4.2-5.0L Blown Gas Modified Sports Car

  3. #138
    deadringer's Avatar
    deadringer is offline Cadillac Owners Fanatic
    Automobile(s): Modified 06 XLR-V
    Join Date
    Jul 2004
    Location
    Houston, TX
    Posts
    152

    Re: RATTLE Snake Bite the XLR-V

    I'm in no way of advocating adding NOS - I generally don't like anything I constantly have to fiddle with to work right (is the bottle full? is the bottle valve open? blah blah)

    But getting the engine to rev another 1500rpm could add a lot more boost... and it seems like a mod you could do with the motor still in the car (similar effort to a cam swap in a traditional LS motor). I would think it would be just a simple head removal and a little bench work to swap the springs - maybe a full day of work?

    As for the engine computer - the LC3 uses an E67 computer which is the same computer thats in the ZR1 (LS9) and the CTS-V (LSA) - there doesn't seem to be much difficulty in getting E67 to do what they need to do... I've been using EFIlive to tune mine and I can't imagine what you couldn't adjust... i've been messing with everything from fuel to even the cam timings. The older northstars used a unique computer, but I haven't heard any issues with the E67... Do you know what limitations they're running into?

    I don't have any desire for the numbers that you're putting out on your XLR-V but if I were, I would be visiting CHRF to see what they can really do... sometimes you end up running into the right guy and magic happens... there's a post in their forums talking about how they are coming out with a whole bunch of bolt-on's for the VVT-based northstar motors so it looks like they've made some progress at least in the past few months.

    I don't disagree with you regarding the trans and diff - the diff busts out in corvettes all the time so thats not news... as for the 6L80e, with some massaging of the torque-management and TCC lockups I think you could get it to last a long while

    Well - regardless, I thought it was worth noodling on.

    ----------

    Quote Originally Posted by deadringer View Post
    But getting the engine to rev another 1500rpm could add a lot more boost... and it seems like a mod you could do with the motor still in the car (similar effort to a cam swap in a traditional LS motor). I would think it would be just a simple head removal and a little bench work to swap the springs - maybe a full day of work?
    Looks like it may not be that hard - apparently you can change the springs with the head still on the block... the service manual calls for tool "J 44211 On-Vehicle Valve Spring Compressor"

    Code:
    Kent-Moore Tools
    Kent-Moore J-44211 Valve Spring Compressor
    
    For General Motors. The new 4.0/4.6 Premium V8 Engines have valve springs which
     are recessed  in the cylinder head.  Standard valve spring compressing tools will not  work. 
     
    J-44211 mounts directly to the cylinder head and will service  four valves in a single mounting position.
    I'm not saying that *I* would be willing to do it, but it would seem to save a lot of labor if you could just pop the valve covers and just go at it... the procedure looks pretty straight forward in the service manual...

    just a thought...

  4. #139
    GizmoQ's Avatar
    GizmoQ is offline The Last Good Gremlin
    Automobile(s): 06 XLR-V and 96 Eldorado ESC-V -- One day ;)
    Join Date
    Mar 2007
    Location
    St Louis, MO
    Posts
    2,631

    Re: RATTLE Snake Bite the XLR-V

    Good bye Florida.



    On my way to W4M within the week. We'll tune the Meth and take advantage of the chiller.
    Snake Bit Super Chilled Black Raven 2006 Cadillac XLR-V aka Elwood (Jake's brother)
    Verified 501rwhp and 486TQ at 6000RPM so far...final goal 575/550

    ELWOOD - "Corvette in a Tuxedo ... with a Jet Pack"



    2013 St Louis Region SCCA Solo SSM Class Champion
    Texas Mile Record Holder: Street Legal XLR @ 159.5MPH
    ECTA LSR Record Holder: 4.2-5.0L Blown Gas Modified Sports Car

  5. #140
    coati's Avatar
    coati is offline Cadillac Owners Fanatic
    Automobile(s): Cadillac
    Join Date
    Mar 2007
    Location
    The SF Bay Area
    Posts
    185

    Re: RATTLE Snake Bite the XLR-V

    Elwood is looking good!

    Have a great road trip and keep us posted on how the tuning goes.

  6. #141
    TimmyC is offline Cadillac Owners Connoisseur
    Automobile(s): 99 SLS and Turbo 07 STS-V-Now back to Supercharged
    Join Date
    Feb 2009
    Location
    1/2 hr S of Grand Rapids, MI
    Age
    35
    Posts
    1,569

    Re: RATTLE Snake Bite the XLR-V

    Quote Originally Posted by deadringer View Post
    I'm in no way of advocating adding NOS - I generally don't like anything I constantly have to fiddle with to work right (is the bottle full? is the bottle valve open? blah blah)

    But getting the engine to rev another 1500rpm could add a lot more boost... and it seems like a mod you could do with the motor still in the car (similar effort to a cam swap in a traditional LS motor). I would think it would be just a simple head removal and a little bench work to swap the springs - maybe a full day of work?

    As for the engine computer - the LC3 uses an E67 computer which is the same computer thats in the ZR1 (LS9) and the CTS-V (LSA) - there doesn't seem to be much difficulty in getting E67 to do what they need to do... I've been using EFIlive to tune mine and I can't imagine what you couldn't adjust... i've been messing with everything from fuel to even the cam timings. The older northstars used a unique computer, but I haven't heard any issues with the E67... Do you know what limitations they're running into?

    I don't have any desire for the numbers that you're putting out on your XLR-V but if I were, I would be visiting CHRF to see what they can really do... sometimes you end up running into the right guy and magic happens... there's a post in their forums talking about how they are coming out with a whole bunch of bolt-on's for the VVT-based northstar motors so it looks like they've made some progress at least in the past few months.

    I don't disagree with you regarding the trans and diff - the diff busts out in corvettes all the time so thats not news... as for the 6L80e, with some massaging of the torque-management and TCC lockups I think you could get it to last a long while

    Well - regardless, I thought it was worth noodling on.

    ----------



    Looks like it may not be that hard - apparently you can change the springs with the head still on the block... the service manual calls for tool "J 44211 On-Vehicle Valve Spring Compressor"

    Code:
    Kent-Moore Tools
    Kent-Moore J-44211 Valve Spring Compressor
    
    For General Motors. The new 4.0/4.6 Premium V8 Engines have valve springs which
     are recessed  in the cylinder head.  Standard valve spring compressing tools will not  work. 
     
    J-44211 mounts directly to the cylinder head and will service  four valves in a single mounting position.
    I'm not saying that *I* would be willing to do it, but it would seem to save a lot of labor if you could just pop the valve covers and just go at it... the procedure looks pretty straight forward in the service manual...

    just a thought...
    Adding RPM to a motor with a supercharger that is already spinning much faster than stock is not going to increase power output. His current 7000rpm is already past the power peak of the engine. If anything boost will decrease as the engine outruns the capacity of the blower.

    CHR might have some experience with camshafts on these but I'm not sure how much they have done with the RWD motors.

    I agree that the E67 will work great at the power levels Giz has in mind. Mine worked fine at 575/621 when I had the turbo on it. The transmission didn't hold up but the computer and rear end were ok.

  7. #142
    deadringer's Avatar
    deadringer is offline Cadillac Owners Fanatic
    Automobile(s): Modified 06 XLR-V
    Join Date
    Jul 2004
    Location
    Houston, TX
    Posts
    152

    Re: RATTLE Snake Bite the XLR-V

    Quote Originally Posted by TimmyC View Post
    Adding RPM to a motor with a supercharger that is already spinning much faster than stock is not going to increase power output. His current 7000rpm is already past the power peak of the engine. If anything boost will decrease as the engine outruns the capacity of the blower..
    Is that really true? In the ECM calibrations the VVT has a max rpm default setting of 6800rpm (or somehting like that) and slams back to 0deg before 7k rpm or above... that could be one reason why you see it drop off in power beyond 7k. It would be worth checking to making sure that isn't an issue.

    Also - even if the power drops off a bit beyond 7k, you could still get remarkable 0-60 times since you could stay in 1st the entire way up to 65mph (assuming you haven't changed the rear diff ratio).

    Quote Originally Posted by TimmyC View Post
    CHR might have some experience with camshafts on these but I'm not sure how much they have done with the RWD motors.
    From what I've read - they seem to be working on the RWD motors too - suggesting they may roll out some bolt-ons for the new motors... and they also say that there's actually very little difference between the FWD and the RWD engines other than VVT and some upgraded features (like they fixed the head blot threading).

    Quote Originally Posted by TimmyC View Post
    I agree that the E67 will work great at the power levels Giz has in mind. Mine worked fine at 575/621 when I had the turbo on it. The transmission didn't hold up but the computer and rear end were ok.
    There's probably going to be a lot more E67 hacking going on now with the ZL1 rolling out with the LSA motor as well... I doubt the ECM will ever be a problem for big power.

  8. #143
    TimmyC is offline Cadillac Owners Connoisseur
    Automobile(s): 99 SLS and Turbo 07 STS-V-Now back to Supercharged
    Join Date
    Feb 2009
    Location
    1/2 hr S of Grand Rapids, MI
    Age
    35
    Posts
    1,569

    Re: RATTLE Snake Bite the XLR-V

    More rpm is not the answer with a roots supercharger. Centrifugal yes, roots no. The roots upercharger just gets pushed even further out of its efficiency range. Power will drop to the point where it's advantageous to shift gears well before 8500rpm.

    Timing and rev limits are easy to tune. I am sure Giz's car has had that addressed.

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