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Timing adjustments
Posted: Sun Jul 06, 2008 7:27 am
by rickssz
Can you tell me bumping timing at which rpm range gives more SOP TQ 1/1.8 or 2/4 or 4/7K or would you decrease timing to come off the line quicker and harder. A4 trans.
RE: Timing adjustments
Posted: Sun Jul 06, 2008 9:58 am
by 06MonteSS
you'd have to be on a dyno to figure that out...
RE: Timing adjustments
Posted: Sun Jul 06, 2008 11:16 am
by rickssz
Why do we have 3 different RPM ranges to adjust timing?
RE: Timing adjustments
Posted: Sun Jul 06, 2008 12:40 pm
by 06MonteSS
so you can do like what you said... adjust each range to get the most power... but to do it accurately, you should really be on a dyno...
or, do it the ol' general way... increase timing till you see KR, then back it down a couple clicks...
but, increasing timing does not always create more power - could actually make less... that's why you'd want to be on a dyno to check...
RE: Timing adjustments
Posted: Sun Jul 06, 2008 4:09 pm
by rickssz
Work with me, would increasing timing in the 4 to 7K range give more torque or thrust from a dead stop hole shot?
RE: Timing adjustments
Posted: Sun Jul 06, 2008 4:28 pm
by 06MonteSS
work with you... hahaha... ok...
sure, go ahead
just monitor your KR levels
Re: RE: Timing adjustments
Posted: Sun Jul 06, 2008 4:28 pm
by CANUCKPREDATOR
06MonteSS wrote:increasing timing does not always create more power - could actually make less... that's why you'd want to be on a dyno to check...
what he said ^^^
RE: Re: RE: Timing adjustments
Posted: Sun Jul 06, 2008 5:13 pm
by BriVG
For a good launch your not going to be revving to 4K, you'd smoke the tires! Hell, with an A4, there prolly spinnin' standin' still. So the timing increase is pointless for that scenario.As Monte said, increase (bottom and middle ranges in your case, one range at a time) and check for KR. Repeat if necessary.
RE: Re: RE: Timing adjustments
Posted: Sun Jul 06, 2008 5:24 pm
by rickssz
OK were making progress, no 4 to 7. The launch that I am referring to is flooring from idle so can I assume the 2 to 4 adjustment wouldnt affect the launch either or would there be an over lap and it would take adjusting both to get the best hole shot? Also I realize I can check each for KR what I am looking for is the most SOP or torque off the line. Thanks.
RE: Re: RE: Timing adjustments
Posted: Sun Jul 06, 2008 5:31 pm
by BriVG
Flooring from an idle with a ride with any kind of power at all is gonna give you wheel spin, wheel spin = crappy launch. Have a friend ride with you when you practice launching to verify the RPM range that your in on a good hard launch with little or no spin. Then you can go and tweek your timing in the correct range. + or - 5 on the predator = 1 degree if I'm not mistaken.
RE: Re: RE: Timing adjustments
Posted: Sun Jul 06, 2008 8:19 pm
by rickssz
Im just not asking the right question. Launch at idle 650rpm and with minor wheel spin its past 2k pretty quick less spin maye a little longer so in the 1 to 1.8 spark range do I increase or decrease timing to get more torque and wheel spin? And since with spin it hits 2k quickly do I increase or decrease timing in the 2 to 4k range to keep the torque up or doesnt it matter once it gets to this point? Im not looking for a guarantee or a magic formula just an opinion with a basis. Thanks.
RE: Re: RE: Timing adjustments
Posted: Mon Jul 07, 2008 11:17 am
by BriVG
Your wheel spin is directly related to your right foot, feather the throttle to minimize spin. As far as power goes, your not gonna really know unless your on the dyno, that being said, you can maximize your spark advance by logging with the predator if yours has that capability. Increase spark in each range (though from what you said probably only the second range) and go do some logging. Download your log to the PC and evaluate for KR on heavy throttle, you'll want to be 26-28 with NO KR.
Posted: Mon Jul 07, 2008 4:23 pm
by ches111
Rick,
Monte gave you the correct answer. You can NOT judge torque and HP just from advancing/retarding the timing. At some point in the course of you advancing timing there will be a point of diminishing returns.
so it would/could look alot like this:
increase 1 degree - power better
increase another 1 degree - power better - still no KR
increase another 1 degree - power worse - still no KR
increase another 1 degree - power worse - still no KR
increase another 1 degree - power worse - now you have KR
So in the above you could have stopped after the first two degrees with no KR and better power/torque. The third forth and fifth adjustments could have actually been NOT ONLY NOT NECESSARY but taking you closer to having KR with no real returns.
This is why he suggested that you go to a DYNO to adjust those ranges.
He also suggested the "OLD DOG" method where you adjust the RPM range up until you see KR and back off from there. Then move to the next range and do the same.
This works really good until you change ANY of the parameters that got you to that level of timing without KR -- Heat/Cold (ambient temps), Fuel used, ...
Good luck.
Only other thing I could offer is to also make an adjust ment montior for KR and put it on the track with multiple runs to see if you are dialing in or making it work. 1 run will NOT do it. May turn out you just had your best timing of YOUR life but the vehicle was NOT at the right timing. So make multiple runs at the track to trend out driver tolerances.
Posted: Mon Jul 07, 2008 9:35 pm
by BriVG
Good advice here Rickssz ^
Posted: Tue Jul 08, 2008 4:59 am
by BoostFrenzy
regarding timing, there's only one "right" curve and while the predator's adjustments seem to be offsets in ranges rather than absolute numbers you can dial in per rpm, this is how i'd approach it...
first you need to understand MBT (maximum brake torque), often referred to as maximum best timing, this is the "right" amount of timing that will produce the most power... and adding in more isn't going to make any more power, you'll just get closer to detonation and have no ceiling for changing atmospheric conditions / fuel quality
so if it's "off the line" power you want, i'd try adding in a little timing in the lower 2 ranges and see how it reflects your 60' times after SEVERAL passes, while also logging KR, beyond that, if you're trying to tune the entire timing curve there's always been two schools of thought here... richer afr's with more timing or leaner with less timing, not sure which makes the power in our cars though because I've never tuned one (yet)
It's really a guessing game without having a dyno to see where MBT is at each rpm, but i'd have to believe adding in a degree or two can't hurt