LT1 B/D PCM tune vs LT1 F/Y Tune
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
Results 1 to 6 of 6
Cadillac Powertrain Control Module (PCM) Tuning Discussion, LT1 B/D PCM tune vs LT1 F/Y Tune in Cadillac Engine Technical Discussion; Something I have noticed, all the B/D cars have a 20 degree offset on the timing table, and the F/Y ...
  1. #1
    N0DIH's Avatar
    N0DIH is offline Cadillac Owners Master
    Automobile(s): 94 Fleetwood Brougham
    Join Date
    Aug 2004
    Location
    Rockford, IL
    Age
    47
    Posts
    7,490

    LT1 B/D PCM tune vs LT1 F/Y Tune

    Something I have noticed, all the B/D cars have a 20 degree offset on the timing table, and the F/Y cars don't.

    I think I found out why.

    The Timing tables can go from 0 to 110 degrees. But there are some places in the timing table that GM goes negative in the B/D tune at a couple places in the timing table. The F/Y tune does not go negative.

    Simple!

  2. Remove Advertisements
    CadillacForums.com
    Advertisements
     

  3. #2
    bigbluebrougham's Avatar
    bigbluebrougham is offline Cadillac Owners Fanatic
    Automobile(s): 1995 Cadillac Fleetwood Brougham
    Join Date
    Nov 2006
    Location
    South Dakota
    Age
    33
    Posts
    118

    Re: LT1 B/D PCM tune vs LT1 F/Y Tune

    Any particular reason?? I am so new at all this, just wondering why they did that...

    BBB

  4. #3
    N0DIH's Avatar
    N0DIH is offline Cadillac Owners Master
    Automobile(s): 94 Fleetwood Brougham
    Join Date
    Aug 2004
    Location
    Rockford, IL
    Age
    47
    Posts
    7,490

    Re: LT1 B/D PCM tune vs LT1 F/Y Tune

    Just what I said, they can push the timing below 0 degrees. The stock B/D has negative timing, the stock F/Y doesn't, so they don't need to.

  5. #4
    bigbluebrougham's Avatar
    bigbluebrougham is offline Cadillac Owners Fanatic
    Automobile(s): 1995 Cadillac Fleetwood Brougham
    Join Date
    Nov 2006
    Location
    South Dakota
    Age
    33
    Posts
    118

    Re: LT1 B/D PCM tune vs LT1 F/Y Tune

    I guess what I meant is why would a car go below zero in timing, moreover, is it good?? Must be since my car still runs good! I just don;t have the slightest clue what a timing table is. My old pickup I know you have initial and total timing, that I understand. Is this the same?

    BBB

  6. #5
    N0DIH's Avatar
    N0DIH is offline Cadillac Owners Master
    Automobile(s): 94 Fleetwood Brougham
    Join Date
    Aug 2004
    Location
    Rockford, IL
    Age
    47
    Posts
    7,490

    Re: LT1 B/D PCM tune vs LT1 F/Y Tune

    They have it set to do it in odd conditions like super low vacuum and low rpm. Like engine start. If you get very high at that condition you can get starting pinging.

    My 454 sees 0 degrees timing factory at high load conditions. Even negative timing. There is initial timing in the PCM tune, but it is the closed throttle timing now, and the timing maps handle it all now. There isn't "advance" like in a distributor anymore...

  7. #6
    bigbluebrougham's Avatar
    bigbluebrougham is offline Cadillac Owners Fanatic
    Automobile(s): 1995 Cadillac Fleetwood Brougham
    Join Date
    Nov 2006
    Location
    South Dakota
    Age
    33
    Posts
    118

    Re: LT1 B/D PCM tune vs LT1 F/Y Tune

    Now I get it!!

    Thanks for the clarification!

    BBB

    P.S. As soon as my laptop is done in the shop, (friend is fixing it for free, for some reason he is slow on fixing it, can't complain, free fix!). I will let you know on the tuning part.

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