Results 1 to 5 of 5

Thread: Reducing torque for smoother city-cruising

  1. #1
    Junior Member carl0s's Avatar
    Join Date
    Oct 2009
    Posts
    19

    Default Reducing torque for smoother city-cruising

    Hi.
    Regarding my LS2/T56 from a 2005 GTO,

    Is there any way of somehow making the engine feel less like a 2v/cyl 6.0 liter V8, and more erm, well less torquey at low throttle input? So more like a modern multi-valve DOHC engine (i.e. little torque at low rpm)?
    When cruising in my LS2 RX7, it's kind of a fine balancing act with the throttle to avoid jerkiness. I just wonder if there's any kind of exponential available on the throttle input, or some engine torque reduction, or some other clever way of improving the car's manners at low speed city driving (>1,800 rpm, low speed, light throttle).

    If the answer is "don't be stupid. It's a 6L pushrod V8", then fair enough, but I figure it's always worthwhile asking. My car is a daily driver, so noises, roughness, and bad manners are something that I'm slowly trying to iron out.

    cheers,
    Carl
    --
    Carl

  2. #2
    Lifetime Member
    Join Date
    Dec 2007
    Posts
    1,143

    Default

    Quote Originally Posted by carl0s View Post
    Hi.
    Regarding my LS2/T56 from a 2005 GTO,

    Is there any way of somehow making the engine feel less like a 2v/cyl 6.0 liter V8, and more erm, well less torquey at low throttle input? So more like a modern multi-valve DOHC engine (i.e. little torque at low rpm)?
    When cruising in my LS2 RX7, it's kind of a fine balancing act with the throttle to avoid jerkiness. I just wonder if there's any kind of exponential available on the throttle input, or some engine torque reduction, or some other clever way of improving the car's manners at low speed city driving (>1,800 rpm, low speed, light throttle).

    If the answer is "don't be stupid. It's a 6L pushrod V8", then fair enough, but I figure it's always worthwhile asking. My car is a daily driver, so noises, roughness, and bad manners are something that I'm slowly trying to iron out.

    cheers,
    Carl
    You could try both...reducing torque B2514 and reducing throttle open rate...B2804, but looks like B2804 is not in there for E40's... :(

  3. #3
    swingtan
    Guest

    Default

    It really depends on the exact reason for the current issue. The car shouldn't feel jerky, so it may be that some parts of the tune are not working right. What are the exact issues you are trying ti iron out? Do you have any log files that show the problem ?

    Simon.

  4. #4
    Lifetime Member
    Join Date
    Dec 2007
    Posts
    1,143

    Default

    Quote Originally Posted by swingtan View Post
    It really depends on the exact reason for the current issue. The car shouldn't feel jerky, so it may be that some parts of the tune are not working right. What are the exact issues you are trying ti iron out? Do you have any log files that show the problem ?

    Simon.
    Actually light cars with large engines and light throttles this is a pretty normal PITA. Even for normal production cars. BMW E46 M3 was great at it. Just gotta take the foot off the pedal and start again.

    But if the E40 had a table that reduced throttle sensitivity down low like they do with 4X4 trucks in low range, this would certainly help to "tune" it out. GM dulls the Corvette throttle substantially at low pedal angles to stop this 1500kg car buck jumping.

    Edit - might have an answer for you. PM me if you want me to take a look at your tune and dull the throttle down.
    Last edited by gmh308; May 25th, 2011 at 02:17 AM. Reason: Edit.

  5. #5
    swingtan
    Guest

    Default

    yes, I know what you mean about light cars......

    The usual issues I've seen with "jerkiness" though ( talking tuned Gen IV ) are...

    • bucking at light throttle, low speed, low load. Usually between 1200 and 1600 with a steady throttle.
    • sudden "jump to life" when off throttle and then very light throttle is applied.
    • rough gear changes in a manual.
    • harsh exit from DFCO when cruising.


    all of these are usually a pointer to the fueling being off, hence why I'd like to see some log data. Otherwise, just go with gmh308's offer via PM, I think he may have a trick or two up his sleeve.

    Simon

Similar Threads

  1. smoother idle
    By southern in forum Custom Operating Systems
    Replies: 0
    Last Post: October 15th, 2010, 01:10 PM
  2. AutoVE Tuned my cruising cells...
    By turboberserker in forum Gen III V8 Specific
    Replies: 0
    Last Post: September 7th, 2009, 06:56 AM
  3. Reducing Smoke
    By killerbee in forum Duramax 06 LLY / 06+ LBZ & LMM
    Replies: 6
    Last Post: July 10th, 2009, 02:22 AM
  4. Stuttering whilst cruising
    By hquick in forum General (Petrol, Gas, Ethanol)
    Replies: 3
    Last Post: April 27th, 2007, 01:30 AM

Posting Permissions

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