Install the TCG app
how_to_install_app_on_ios
follow_along_with_video_below_to_see_how_to_install_our_site_as_web_app
Note: this_feature_currently_requires_accessing_site_using_safari
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an alternative browser.
You should upgrade or use an alternative browser.
More options
Who Replied?Negative timing is "retarded" timing (retarded, yes, but i mean retarded in the technical, reducing term). I have never heard of a GP with negative timing. It's more common in cars with distributors while combating detonation, and even then, it is still not common.
Here is, basically, how timing works on most computer controlled cars. More specifically, non-supercharged L36s:
Starts at a medium timing number, say 20. Assuming there is no knock, timing is advanced 1 degree every certain # of cycles of the computer. I dont remember how long the interval is. It may be every second, and more or less. It keeps increasing timing until it reaches anything resembling knock (.1*). It then retards your timing 3*. If it sees no knock, it will increase timing until it does see it, then retard timing even more.
Knock retard is defined as how much timing (in degrees) is pulled/reduced/retarded when the engine experiences detonation. Increased detonation/knock = more knock retard = less timing = less power/fuel economy.
There is usually a maximum timing a computer can handle. The computer's tables will not handle more than that without being stressed out. Therefore, you will never see outrageous numbers such as 62* timing advance (it is capped). People will manually advance their timing, fooling the computer into thinking it can easily handle it. The PCM usually doesn't know how to compensate for it, which is why everyone will caution you to not run too much timing, or you can blow a motor.
"Cam sig present" means cam signal present. AKA, your computer recognizes your CPS (Camshaft Position Sensor). Probably just a scanner settings.
Try using something more accurate than a Snap-On scan tool. I used a snap on scanner on my car and it was the biggest POS i have ever used. Totally wasn't meant for newer cars, even though it was compatible.
Any more questions feel free to ask...i'll answer to the best of my ability.
Here is, basically, how timing works on most computer controlled cars. More specifically, non-supercharged L36s:
Starts at a medium timing number, say 20. Assuming there is no knock, timing is advanced 1 degree every certain # of cycles of the computer. I dont remember how long the interval is. It may be every second, and more or less. It keeps increasing timing until it reaches anything resembling knock (.1*). It then retards your timing 3*. If it sees no knock, it will increase timing until it does see it, then retard timing even more.
Knock retard is defined as how much timing (in degrees) is pulled/reduced/retarded when the engine experiences detonation. Increased detonation/knock = more knock retard = less timing = less power/fuel economy.
There is usually a maximum timing a computer can handle. The computer's tables will not handle more than that without being stressed out. Therefore, you will never see outrageous numbers such as 62* timing advance (it is capped). People will manually advance their timing, fooling the computer into thinking it can easily handle it. The PCM usually doesn't know how to compensate for it, which is why everyone will caution you to not run too much timing, or you can blow a motor.
"Cam sig present" means cam signal present. AKA, your computer recognizes your CPS (Camshaft Position Sensor). Probably just a scanner settings.
Try using something more accurate than a Snap-On scan tool. I used a snap on scanner on my car and it was the biggest POS i have ever used. Totally wasn't meant for newer cars, even though it was compatible.
Any more questions feel free to ask...i'll answer to the best of my ability.
I
imported_Ron Vogel
Guest
Some scanners read it backwards, it also depends on the year. Normally we're dealing with 15 deg of WOT timing. So 5KR, and 10 degrees of timing sounds about right. A lot of people get KR form simple things, so I'd go after those first. Fresh oil change, reducing carbon build up, etc. Then I'd start going after fuel ratio next, then look into colder plugs.
F
fastcash
Guest
Originally posted by Ron Vogel@Nov 6 2004, 12:21 PM
Some scanners read it backwards, it also depends on the year. Normally we're dealing with 15 deg of WOT timing. So 5KR, and 10 degrees of timing sounds about right. A lot of people get KR form simple things, so I'd go after those first. Fresh oil change, reducing carbon build up, etc. Then I'd start going after fuel ratio next, then look into colder plugs.
[snapback]59397[/snapback]
Fresh oil change: already done ( mobile 1 synth, mobile 1 98 blazer oil filter)
reduce carbon build up: how? i run race gas once a month, does that help?
how can i change the a/f ratio?
mods include 3.4", no u-bend, intake, and later today auto lite 104's
i will be scanning the car after i put in the 104's and if still knock, i will add a few gal of 100 octane and scan again.
will post the results