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How to scale timing table for most power??

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Old 10-18-2005, 05:50 PM
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Default How to scale timing table for most power??

I searched and still haing a hard time. Trying to get insight as to how to adjust my timing tables for the power for my heas/cam setup.
O have found that, increasing my timing in the lower load ranges by 5 or 6 deg. really wakes up the bottom end torgue, and does not cause any KR. But adding that much timing to the entire table does not seem to work well, I can tell no benefit of it at higher loads (gms/cyl) .
So, what I been doing is, increassing timing values by 5 deg for the first five or six rowes in the table (.08 to .028 gms/cyl) , then adding less timing, say 4 deg for the next 4 or five rows, then 3 deg. for the next 4 or 5 rows, and so on until i get all the over to the 1.20 gms/cyl. row. I'm thinking, probably after about .6 gms/cyl, I need to taper off the advance more quickly, down to say 28 deg at full load ?
Is this any kind of way to scale the timing tables? I'm a newbie to this, just trying to get some kind of tune going. Got my LTFT's to near zero, now trying to get timing maximized.
Plesae help point me in the right direction !

Last edited by T/A rocker; 10-19-2005 at 07:41 AM.
Old 10-19-2005, 09:43 AM
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Anybody ??

I've been looking at a lot of .BIN files for cars with similar mods to mine, and the timing looks one hell of a lot differerent that the stock tables!
But I don't want to just copy someone else's tables, besides each car tunes differently.
Want to know how they went about doing these adjustments to the timing curve, there has to be a mthod to the madness.
Come on tuning experts, share your thoughts !


Sorry, I'll shut up now, and let this thread marinate a while...
Old 10-19-2005, 10:50 AM
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I would like to know more about this aswell
Old 10-19-2005, 10:57 AM
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go to horists website download jimmyblues tune look at his timing tables and copy the way he does it
Old 10-19-2005, 01:04 PM
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IMO, you need to get on a load dyno. If you have something like EFILive, you can alter timing real time (however the changes don't remain, i.e. they are temporary). You want to keep the car in a steady state position, keep adding timing until you see no more improvement in torque without experiencing knock. There is definitely a point of diminishing returns in which more timing will not add any more torque (in fact it may decrease it), but it will put you closer to the point of knock. Many people that only tune on the street simply use the method of adding timing until knock is induced then backing off a couple of degrees. The problem with that method is that you really don't know where maximum torque occurred. For example, I see a lot of tunes with 28* timing in which people indicate that 30* induced knock. So, they reduced it to 28*. What if max torque was achieved with only 26*?

Without the right tool (a load dyno), I think you will always be less certain about the 'right' amount of timing. This is a time consuming process on LSx's because of our inability to perform real time tuning. It also slightly complicated by the fact that the timing table uses g/cyl versus say kPa.

Just my $.02
Old 10-19-2005, 01:15 PM
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I am curious to this as well and was going to ask the same question on another forum but decided to read some more first. It was so easy in the old days, just turn the distributor for max advance and adjust the curve with springs and weights.

I think it's safe to say, most tuners just tune for WOT. Set the AFR to 12.8-13 to 1 and timing around 28* give or take a degree. What happens in the middle is not too important.
Old 10-19-2005, 01:19 PM
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Originally Posted by superls1
IMO, you need to get on a load dyno. If you have something like EFILive, you can alter timing real time (however the changes don't remain, i.e. they are temporary). You want to keep the car in a steady state position, keep adding timing until you see no more improvement in torque without experiencing knock. There is definitely a point of diminishing returns in which more timing will not add any more torque (in fact it may decrease it), but it will put you closer to the point of knock. Many people that only tune on the street simply use the method of adding timing until knock is induced then backing off a couple of degrees. The problem with that method is that you really don't know where maximum torque occurred. For example, I see a lot of tunes with 28* timing in which people indicate that 30* induced knock. So, they reduced it to 28*. What if max torque was achieved with only 26*?

Without the right tool (a load dyno), I think you will always be less certain about the 'right' amount of timing. This is a time consuming process on LSx's because of our inability to perform real time tuning. It also slightly complicated by the fact that the timing table uses g/cyl versus say kPa.

Just my $.02
Ok, that's kinda what I figured. You can't really do it right without getting on a dyno, since you can't tell from driving on the street, where you are getting max power / torque.
I just thought there might be a better "steet" way of tuning, than increasing until knock, then backing off a few degrees.
I got my timing table adjusted to where my car feels a lot better now with the cam, so I reckon that'll have to do, until I can get it on a Dyno. Problem is, there ARE NO dyno's around here. I live in East Tennessee, and I have been told by others the closest shop with a dyno is in like North Carolina.
Old 10-19-2005, 01:43 PM
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I know that EFILive has a calc pid that you can log that gives you HP readings. It seems it would be simple enough to make a couple of 4th gear runs to red line and adjust timing accordingly.




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