i dicided to paly with my timing today, made about 15 1/8th mile runs with my timing all over the place.

i left it stock for a few runs, locked it at 20deg, then 24, then 28, then 32. all runs were within 1/10th and 1.5mph with no pattern.

the stock timing puts it at about 28deg to start and drops thru the rpms to something like 18deg.

should i try anything else? where are you guys set at?

i did run a 13.74 at 105 with the cut outs open and stock 6.0 timing. i hope i can pull that at the track(- the standard 4mph for gtech), track opens in 6 days

 

Set it at about 26 and it should be fine for running n/a or with a 125 shot.

 

Set it at about 26 and it should be fine for running n/a or with a 150 shot.

 

I have always done what Hypertech did with there timing increase. Like a coordinate (x,y) on the HOT and LOT timing table grab from cell (0.32, 1600rpm) and highlight from that spot all the way to the bottom right of the table. I increase those only. I have actually graphed a lot of this timing stuff out and you can plot where you are in the table over the entire rpm range.

In edit v1.4 the "x-factor" for truck engine timing is solved. There is a new table that shows a relationship between "Fuel ratio vs. RPM modifier" under ignition. I set this to zero so I know that the only table it can referrence for advance (besides KR) is the HOT table. This is important for boost especially. Before this new table came out I would have it set to see 15* adv. in upper rpms. However I would see something like 24* As you can imagine it is not cool to be unable to control your timing with lots of boost

I have it set to give 20* adv. in upper rpms with the 3.5" pulley. It is starting to warm up in Phoenix now though so that number will probably have to come down a few degrees soon

 

parish, once you get the "boost", you may find that less timing will yield better numbers.

 

I'm wondering the same thing. I always thought more timing is always better.

I recently tuned to right before the point of detonation.

Started at 15 degrees declining to 11 degrees at redline.--ran 14.06 (g-tech)

Ended up at 15 degrees from start to redline--ran 14.00 (g-tech)

I thought I'd get more gains raising timing 4 degrees.

Does anyone know if there is a point where more timing does no good?

 

I try to get at least 24*. I had it up to 28*, but lowered it when I got my nitrous kit finished up. I notice that sometimes it will be in the 20-21* range with certain temps and KR, and other times it will be in upper 20s with the same tune and no KR. I have a really long stretch of roas that I test on. I can do a 0-80 run, immediately stop, then do it again. I've seen low 20s and 5*KR on the first blast, then 0 KR and upper 20s the next. Runs are 1 minute apart. Must have something to do with IAT and ECTs.

 

Yeah, I ended up zeroing my IAT vs. load table just to get some consistency.

 

Do not zero your IAT vs MAP table, Black Blown 02. You can run alot of timing down low, for a huge torque increase. Then you can slowly take timing out as the air temp goes up.
On the dyno 2* of timing at low rpms was worth 11rwtq, with my ATI. I had my timing set at 28* with pump gas at 11lbs, no detonation problems. As the air temp went up I started taking timing out. First by 1 and 2 degress and then as the air got hot 6 to 10 degress.
Just my opinion.

 

When you say alot of timing down low, what rpm do you mean?

Right now, I run 20 degrees until 4200 rpm, then 18 until 5000, then 15 from 5000 to 6000 (where 90 percent of the 1/4 mile run is.) I stall to 4000 and my shifts drop to 5000.

I like that idea. If the outside temp will stay consistent around here I will try it.