Results 1 to 7 of 7

Thread: 18rg tuning

  1. #1
    Forum Member
    Join Date
    Sep 2008
    Location
    NSW
    Posts
    2

    Default 18rg tuning

    Hi all
    I've got a 18rg in a RA40 Celica
    Im running a standard engine with a 1111-88250 head
    and 1951-88270 cams ( don't know if the numbers matter)
    and its running the standard solex carbies.

    i have 2 other 18rg heads with numbers 1111-88253
    and they both have cams with numbers 1351-88251
    is there and difference between the numbers is either better

    Im having a bit of trouble getting the motor run right
    the cams are set what i can visually see as 12oclock(notch pointing straight up)
    i've got the ignition set at the 12 degrees before TDC (used a timing light)
    but im still getting blow back through the carbies
    and it seems to run pretty ruff.
    any help would be much appreciated

  2. #2
    Toyota Dealer Team Backyard Mechanic Willofan's Avatar
    Join Date
    Aug 2009
    Location
    NSW
    Posts
    325

    Default Re: 18rg tuning

    Hi,

    Not a total expert but I have come along way to understanding the 18RG beast through reading the following thread;

    http://www.toymods.org.au/forums/showthread.php?t=222

    Based on the description you have already provided, you will need to check valve clearances and compression to make sure you dont have burnt/leaking valves. If these are in spec, then you will need to check carby synchronisation, ign timing advances (mech and Vac), cam shaft timing.

    I am sure there are others on here that can add to this based on their experience.

    Good luck
    Rgds, Willofan
    'Growing Old' Beats 'Dying Young' - Drive sensibly and safely
    http://www.toymods.org.au/forums/showthread.php?t=54206

  3. #3
    Fustrated DYI mechanic Automotive Encyclopaedia Omegaman's Avatar
    Join Date
    Oct 2005
    Location
    Sydney N.S.W
    Posts
    849

    Default Re: 18rg tuning

    Double check your dizzy. even if 1 tooth out, it can play hovac on timing.

  4. #4
    Toyota fanatic Grease Monkey Gttwinturbomk3's Avatar
    Join Date
    Jun 2007
    Location
    Dunedin
    Posts
    138

    Default Re: 18rg tuning

    even if you have only got mildly shaven cams in there it will always run a little rough with the side-draught solex carbs combination on it. Check all the things above especially the valve clearances and compression test it too if your down in one cylinder your clearances are proberly out dont panic though its a simple adjustment.

    As far as i know the head numbers are just from older and newer heads some had different tappet covers but im pritty sure the heads are the same??

  5. #5
    Junior Member Automotive Encyclopaedia roadkill's Avatar
    Join Date
    Apr 2006
    Location
    Queensland
    Posts
    949

    Default Re: 18rg tuning

    Hi,

    cylinder head info

    88210 - smallest valves, biggest cams
    88230 - bigger valves, tamer cams
    88250 - bigger valves again, tamer cams
    88253 - same as 88250 but should have twin valve springs
    88270 - efi, bigger valves and even more tame cams

    The compression ratio also changed in the bottom end through the different head numbers. 88210 had the highest compression going down to the lowest with the 88270

    bEn
    FJ40 landcruiser
    HJ47 landcruiser
    FJ55 Landcruiser
    MS65 Crown

  6. #6
    Forum Member
    Join Date
    Sep 2008
    Location
    NSW
    Posts
    2

    Default Re: 18rg tuning

    thanks for all the input,
    i think it may come down to valve clearance as i know ignition timing is right and cam timing seems pretty close ill check compression on the weekend and measure the shims and go from there.

  7. #7
    Forum Member
    Join Date
    Apr 2006
    Location
    NSW
    Posts
    1

    Default Re: 18rg tuning

    Bush Drifter,

    As other posts have suggested with cam and ignition timing also check the carb idle jets.. if restricted it may be causing a lean mixture causing the backfire.

Similar Threads

  1. The Tuning Talk Thread - Forced Induction EFI & JZ Tuning.
    By JZA70 R in forum Tech and Conversions
    Replies: 450
    Last Post: 26-05-2013, 08:13 PM
  2. 18rg tuning, LONG!
    By rcodea in forum Tech and Conversions
    Replies: 30
    Last Post: 09-10-2006, 01:56 AM
  3. 18RG tuning
    By ROHANVII in forum Tech and Conversions
    Replies: 16
    Last Post: 28-07-2006, 09:33 AM

Bookmarks

Posting Permissions

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