Results 1 to 10 of 10

Thread: Question about base distributor timing & total timing

  1. #1
    Supporting Member Turbo Mopar Contributor A.J.'s Avatar
    Join Date
    Feb 2006
    Location
    Mesa, AZ
    Posts
    2,426

    Question about base distributor timing & total timing

    I'm looking at sample timing tables for boosted engines and their numbers are my total timing numbers (MPTune) if I subtract the 12* BTDC that I set my distributor at. So my question is: While looking at the total timing tables on MPTune, do I need to subtract 12* to get my "actual" total timing.

  2. #2
    Supporting Member II Turbo Mopar Contributor tryingbe's Avatar
    Join Date
    Dec 2005
    Location
    Mesa, AZ
    Posts
    7,187

    Re: Question about base distributor timing & total timing

    No. You do not.

  3. #3
    Buy my stuff!!!!!!!!!!! :O) Turbo Mopar Vendor turbovanmanČ's Avatar
    Join Date
    Dec 2005
    Location
    Abbotsford, BC
    Posts
    44,167

    Re: Question about base distributor timing & total timing

    Its just a reference point, the timing you see is the timing it is, consider 12 at the dizzy 0.
    1989 FWD Turbo Caravan-2.5 TIII, GT35R, auto, a/c, cruise, pwr windows/locks, fully loaded with interior and ran with full exhaust. RETIRED FOR A FEW YEARS! 12.57@104 :O)
    1984 Chev Getaway van, 6.2 Diesel with a remote mounted turbo setup burning WMO-For sale.
    2003 GSW 2.0L TDI, auto, fully loaded, modified, 360K-wife's.
    2004 GSW TDI, 5 speed, fully loaded, modified.

    Aurora ignition wires for sale. Link to info

    Super60 roller cams or custom/billet cams. Link to info

  4. #4
    Supporting Member Turbo Mopar Contributor Ondonti's Avatar
    Join Date
    Dec 2005
    Location
    Seattle
    Posts
    7,025

    Re: Question about base distributor timing & total timing

    Quote Originally Posted by turbovanmanČ View Post
    Its just a reference point, the timing you see is the timing it is, consider 12 at the dizzy 0.
    So how exactly does this work in real live when one is set at 12 and another is set at 14. Are you saying the stock computer will then read higher timing numbers by 2 degrees across the board on a scanner? I am not talking about with a timing light.
    Brent
    GREAT DEPRESSION RACING
    1992 Duster 3.0 The Junkyard- Now - Megasquirt II/Extra. OEM 10:1 3.0 + funny business
    - Old - 11.5@125 22psi $90 Stock 3.0 Junk Motor - 516whp 519wtq 20psi 91 oct built 3.0 stock n/a computer
    1994 Spirit 3.0 - 12.3@113 15 psi - Daily Holset He341 280whp 304ft/lb @10psi
    1994 Spirit 3.0 a670 - Wife's - Disassembled
    1990 Spirit 3.0 E.S. 41TE
    1993 Spirit 3.0 E.S. 41TE
    1994 Duster 3.0 A543
    1990 Lebaron Coupe 2.2 TII non IC, T1 31TH
    1981 Starlet KP61 Potential driver, 1981 Starlet KP61 Parts, 1983 Starlet KP61 Drag
    1998 Dodge 12v Cummins 47re 4x4 4dr longbed. No fuel plate. Mack plug, AFC & Spring mods. Boost elbow.

  5. #5
    Visit www.boostbutton.com... Turbo Mopar Contributor ShelGame's Avatar
    Join Date
    Dec 2005
    Location
    Whitmore Lake, Michigan, Unite
    Posts
    9,918

    Re: Question about base distributor timing & total timing

    Quote Originally Posted by Ondonti View Post
    So how exactly does this work in real live when one is set at 12 and another is set at 14. Are you saying the stock computer will then read higher timing numbers by 2 degrees across the board on a scanner? I am not talking about with a timing light.
    If you set it at 14, the sync will be off by 2deg (advanced). And the computer will then under report by 2deg the actual total timing.

    12 is not "base" timing. Its just the timing the computer uses when you are syncing the distributor to the crank with a timing light. The simple reason for 12deg is that the engine will idle well at 12deg, but not so much at 0.
    https://db.tt/SV7ONZpQ
    Rob Lloyd
    '89 Daytona C/S

    2.5 T1 Auto
    13.24 @ 100.5mph
    NHRA #3728 AF/S

    boostbutton.com
    tuning wiki

  6. #6
    Supporting Member Turbo Mopar Contributor A.J.'s Avatar
    Join Date
    Feb 2006
    Location
    Mesa, AZ
    Posts
    2,426

    Re: Question about base distributor timing & total timing

    Quote Originally Posted by ShelGame View Post
    If you set it at 14, the sync will be off by 2deg (advanced). And the computer will then under report by 2deg the actual total timing.

    12 is not "base" timing. Its just the timing the computer uses when you are syncing the distributor to the crank with a timing light. The simple reason for 12deg is that the engine will idle well at 12deg, but not so much at 0.
    I forgot to mention I'm doing this with a 2.4 DOHC. I have the stock Neon-SRT-4 timing tables. I tried using them but it accelerates like a dog. I tried setting base timing at 0* (idles fine) to see if it makes a difference and it didn't. I tried setting it at 0* using my current timing tables and it didn't make a difference in acceleration. I'm trying to figure out the SMEC's "logic" while trying to calculate my timing curve (part throttle/WOT) but with the '04 Neon SRT-4 using a faster processor and DIS and I'm using a SMEC and a distributor, the SRT-4 might work faster and allow for more timing. With mine running as good as it does using Sean's (1fastcsx) "base" timing, and my adjustments for my set up, I think with my set up that's the best I'm going to get and just street tune/dyno tune from there.

  7. #7
    Moderator Turbo Mopar Staff Force Fed Mopar's Avatar
    Join Date
    Dec 2005
    Location
    Greenville/Spartanburg SC area
    Posts
    7,537

    Re: Question about base distributor timing & total timing

    If you set it to 0*, then it will be running 12* less timing than the timing tables or the scanner will show, which would explain why it is sluggish. Set it to 12* w/ the CTS unplugged, just like you would a 8v, and then make any timing changes needed in the cal.

    The rpm timing table is where you set the base timing. Whatever you have it set to at idle rpm is what your base/initial timing will be. If you want more initial timing, make the timing at 1000 rpm higher.

    In basic terms, the AdvanceFromRPM table replaces the mech advance springs of old-style distributors, and the AdvanceFromMap tables replace the vacuum advance.
    Rob M.
    '89 Turbo GTC
    2.5 TIII swap is here!

    Project LookOwt
    '91 Daytona ES, 61k original miles, Rick Lozier's old 3.0 nitrous car
    Back to basics, then the mods go back on....

  8. #8
    Buy my stuff!!!!!!!!!!! :O) Turbo Mopar Vendor turbovanmanČ's Avatar
    Join Date
    Dec 2005
    Location
    Abbotsford, BC
    Posts
    44,167

    Re: Question about base distributor timing & total timing

    Quote Originally Posted by A.J. View Post
    I forgot to mention I'm doing this with a 2.4 DOHC. I have the stock Neon-SRT-4 timing tables. I tried using them but it accelerates like a dog. I tried setting base timing at 0* (idles fine) to see if it makes a difference and it didn't. I tried setting it at 0* using my current timing tables and it didn't make a difference in acceleration. I'm trying to figure out the SMEC's "logic" while trying to calculate my timing curve (part throttle/WOT) but with the '04 Neon SRT-4 using a faster processor and DIS and I'm using a SMEC and a distributor, the SRT-4 might work faster and allow for more timing. With mine running as good as it does using Sean's (1fastcsx) "base" timing, and my adjustments for my set up, I think with my set up that's the best I'm going to get and just street tune/dyno tune from there.
    That's probably why your van feels slow, your 12 deg retarded from the get go. You are still using a SMEC and SMEC tables, so the 12 deg has to be factored in.
    1989 FWD Turbo Caravan-2.5 TIII, GT35R, auto, a/c, cruise, pwr windows/locks, fully loaded with interior and ran with full exhaust. RETIRED FOR A FEW YEARS! 12.57@104 :O)
    1984 Chev Getaway van, 6.2 Diesel with a remote mounted turbo setup burning WMO-For sale.
    2003 GSW 2.0L TDI, auto, fully loaded, modified, 360K-wife's.
    2004 GSW TDI, 5 speed, fully loaded, modified.

    Aurora ignition wires for sale. Link to info

    Super60 roller cams or custom/billet cams. Link to info

  9. #9
    Supporting Member Turbo Mopar Contributor Ondonti's Avatar
    Join Date
    Dec 2005
    Location
    Seattle
    Posts
    7,025

    Re: Question about base distributor timing & total timing

    So I am seeing only 24 degrees of timing WOT on a stock 1994 3.0 SBEC II @ 5000 rpms and 2" vacuum using DRB II. This seems really low for a 2 valve head when I see the SRT4 stock map is running about 33 degrees of timing on a 4 valve head. I even see 3000gts (the 24 valve turbo version) running more timing at this load point.
    Not sure if this is because of compression ratio but 2 valve heads should run more timing then 4 valves.
    Brent
    GREAT DEPRESSION RACING
    1992 Duster 3.0 The Junkyard- Now - Megasquirt II/Extra. OEM 10:1 3.0 + funny business
    - Old - 11.5@125 22psi $90 Stock 3.0 Junk Motor - 516whp 519wtq 20psi 91 oct built 3.0 stock n/a computer
    1994 Spirit 3.0 - 12.3@113 15 psi - Daily Holset He341 280whp 304ft/lb @10psi
    1994 Spirit 3.0 a670 - Wife's - Disassembled
    1990 Spirit 3.0 E.S. 41TE
    1993 Spirit 3.0 E.S. 41TE
    1994 Duster 3.0 A543
    1990 Lebaron Coupe 2.2 TII non IC, T1 31TH
    1981 Starlet KP61 Potential driver, 1981 Starlet KP61 Parts, 1983 Starlet KP61 Drag
    1998 Dodge 12v Cummins 47re 4x4 4dr longbed. No fuel plate. Mack plug, AFC & Spring mods. Boost elbow.

  10. #10
    Moderator Turbo Mopar Staff Force Fed Mopar's Avatar
    Join Date
    Dec 2005
    Location
    Greenville/Spartanburg SC area
    Posts
    7,537

    Re: Question about base distributor timing & total timing

    Actually I seem to see the opposite, IE my 8v runs way less timing than a 2.4 does. But, it really has more to do w/ the chamber design than the number of valves.
    Rob M.
    '89 Turbo GTC
    2.5 TIII swap is here!

    Project LookOwt
    '91 Daytona ES, 61k original miles, Rick Lozier's old 3.0 nitrous car
    Back to basics, then the mods go back on....

Similar Threads

  1. How do you calculate total timing?
    By turbovanmanČ in forum EFI Tuning
    Replies: 13
    Last Post: 04-30-2013, 06:45 PM
  2. Total Timing Spreadsheet
    By cordes in forum EFI Tuning
    Replies: 8
    Last Post: 08-23-2011, 05:28 PM
  3. Total timing and scan tools
    By Force Fed Mopar in forum EFI Tuning
    Replies: 20
    Last Post: 11-15-2010, 08:59 AM
  4. how much base timing
    By Mr overkill in forum Electrical & Fuel System
    Replies: 8
    Last Post: 10-13-2007, 11:57 PM
  5. Setting base timing
    By The S is Silent in forum Maintenance & General Tech
    Replies: 24
    Last Post: 08-08-2006, 11:02 PM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •