Help Finding the Right Timing at Idle

[bluegoat06]

The car is running stock base spark idle, plus 2* more i added to mess with it, but then i've been reading i should match the base spark idle with the coastdown idle and the High octane table. what are the benefits in doing this ? and how can i know the right amount of timing i should have at idle ?
if i add, should i add to the base timing, or remove from the high octane table, and if i add to both, (base and HO), should i remove from coastdown ??


Car and mods in the sig, i'm also attaching the current HPT file i'm working with.

Thanks

[bluegoat06]

Anybody ?

[EC_Tune]

Correct. Idle and coastdown spark should be exactly the same in the idle range. Coastdown spark can be lower than idle spark above the idle range though.

[bluegoat06]

Thanks EC tune,
I'm trying to get rid of the KR i have when doing WOT runs from a dig, oe even just driving spirited with not much throttle
I'll attach a log to give a better example..

I wonder how can i fix the issue ?, why do i have KR at low RPM ?

[ShoddyHog]

FWIW, mine does that a lot when I'm doing my VE tuning...not so much after going back to closed loop. (or at least re-enabling the MAF)

I also noticed that with the exception of a couple areas of your timing table that are rarely touched, it appears as thought it is the stock table +2. I haven't read what the "proper" way is to tune the timing tables, but I think you'd do a lot better to return back to stock, then add in timing in three areas: Idle, cruise, and WOT.

Also, I believe most people recommend having your high octane match your low octane. Then again, I always have 93 octane available.

I also do not have my idle and coast down set to the same as my high octane. I had all kinds of problems doing that, and it didn't get better until I returned those tables similar to the stock configuration.

Gerry

[ShoddyHog]

Here's my timing tables...this works perfectly for me. No bucking, surging, or stalling. I can pretty much run down to 1250 rpm without any surging, and can even just let off the clutch on flat ground albeit a little jerky, but I can do it. I also walk up wheel ramps without touching the throttle...same goes for backing up my steep linclined driveway into the garage.

Gerry

[bluegoat06]

Shoddy, do you still see KR in the same areas as mine with stock timing at such rpm ? 1800-2400rpm.., do you think those 2* more than stock are messing things around those RPM ?

It seems i see the most KR during hard throttle changes, (cruising to spirited driving or when launching more or less hard with half throttle runs).

[ShoddyHog]

Shoddy, do you still see KR in the same areas as mine with stock timing at such rpm ? 1800-2400rpm.., do you think those 2* more than stock are messing things around those RPM ?

It seems i see the most KR during hard throttle changes, (cruising to spirited driving or when launching more or less hard with half throttle runs).

Don't know enough to tell you for sure, but I know if I go out and try to induce those spikes I can whether I have +2 over stock or stock timing, and those sharp throttle changes produce that at lower RPM's rather than high. I think it's calle tip-in KR.

As far as normal driving goes, it seems like I see a lot more of that from slight throttle transitions when I'm VE tuning with the MAF failed. Maybe that (and it being easier to cause at lower rpm) is because at lower rpm, you're not running strictly off of the MAF???

When I get it all figured out, I'll let you know...should be somewhere in 2009 or 2010

Gerry

[svede1212]

FWIW, mine does that a lot when I'm doing my VE tuning...not so much after going back to closed loop. (or at least re-enabling the MAF)

I also noticed that with the exception of a couple areas of your timing table that are rarely touched, it appears as thought it is the stock table +2. I haven't read what the "proper" way is to tune the timing tables, but I think you'd do a lot better to return back to stock, then add in timing in three areas: Idle, cruise, and WOT.

Also, I believe most people recommend having your high octane match your low octane. Then again, I always have 93 octane available.

I also do not have my idle and coast down set to the same as my high octane. I had all kinds of problems doing that, and it didn't get better until I returned those tables similar to the stock configuration.

Gerry

that's true for tuning without the MAF but you want to put it back unless you're running SD without the 1 bar enhancement

[ShoddyHog]

that's true for tuning without the MAF but you want to put it back unless you're running SD without the 1 bar enhancement

Thanks...I've been doing it wrong from day one then.

Why do you see people recommend that then? FWIW, when I got my car back from my cam install and tune my high and low both matched as well. Not that he knew what he was doing

Gerry

[ShoddyHog]

I think I'll ask that question over on the GTO forum. Seem to get more responses there.

Gerry

[EC_Tune]

that's true for tuning without the MAF but you want to put it back unless you're running SD without the 1 bar enhancement

That's only true on the Gen III engines not Gen IV as they use HO & LO full time failed MAF or not.

[ShoddyHog]

That's only true on the Gen III engines not Gen IV as they use HO & LO full time failed MAF or not.

Interesting....so leave both of them the same then?

Gerry