FI timing questions
FI timing questions I notice the older cars like 99 have very agressive timing maps especially in the 80 to 120 regions where boost happens. The later cars like 2002 have pretty mellow timing in the same area especially in the idle thru mid 2000rpm range.
So why did they do that on the different years in that region. I guess when they are not FI it wouldn't matter much. So would it be good to keep the timing up nice and high in the 80 to 120 range from idle to right before you start boosting and then ramp it down quick like to say go from 23 degress at 2400 and then 15 at 2800 type of thing or would it be better to do more like later year curves and have timing say gradually coming up from idle like a 8 ,8, 9 10, 10 , 12 gradually rising to max timing after the peak torue point.
One way seems like a sharp wall with lots of timing until boost point,sharp drop off and then bit of increase after peak torque.
Figure while this is a tuning question it is more likely to get relevant answers in this section.
So why did they do that on the different years in that region. I guess when they are not FI it wouldn't matter much. So would it be good to keep the timing up nice and high in the 80 to 120 range from idle to right before you start boosting and then ramp it down quick like to say go from 23 degress at 2400 and then 15 at 2800 type of thing or would it be better to do more like later year curves and have timing say gradually coming up from idle like a 8 ,8, 9 10, 10 , 12 gradually rising to max timing after the peak torue point.
One way seems like a sharp wall with lots of timing until boost point,sharp drop off and then bit of increase after peak torque.
Figure while this is a tuning question it is more likely to get relevant answers in this section.
i like stock timing till boost and then ramp down to 15deg by max boost. 15deg is not the most power but good power...safe and allows you a little leeway in the afr without damage
I ussually settle in from 10 to 20 degrees total, but I deal with weird stuff....like extreme heat in vegas, some heavy vehicles like 6000 lb turbo vans, to 2000 lb turbo sandrails.
Most of the f bodies run 12-14 degrees in street trim and as much as 20-24 on e 85 or race gas and 15-20 psi with low compression end decent weather. Tunes here change a bit from summer to winter.
Most of the f bodies run 12-14 degrees in street trim and as much as 20-24 on e 85 or race gas and 15-20 psi with low compression end decent weather. Tunes here change a bit from summer to winter.
Your timing should ramp down with boost, not specifically with rpm. Take a stock ignition map and load the car where it makes boost at the lowest possible rpm. Start pulling timing as the boost is rising, and ramp0 a few degree's back in after peak torque.
What I was saying though is the 99 and 2002 cars have very different timing tables especially from like 80 to 120g.
I understand to take the timing down when boost is hitting and increase a bit more after peak torque.
But am just wondering the advantages of say having 23 at 2200 from say 80 to 120g or having more like a 02 timing curve from 80 to 120g which is more like 8 ,10, really low compared to the 99 curves. And talking again to say 2200.
I should take some screen shots somehow of a 2002 timing table and a 99 timing table of maybe someone can do that to show the difference. I am taking the timing on boost down a lot of course but talking about the preboost area from 80 to 120.
I understand to take the timing down when boost is hitting and increase a bit more after peak torque.
But am just wondering the advantages of say having 23 at 2200 from say 80 to 120g or having more like a 02 timing curve from 80 to 120g which is more like 8 ,10, really low compared to the 99 curves. And talking again to say 2200.
I should take some screen shots somehow of a 2002 timing table and a 99 timing table of maybe someone can do that to show the difference. I am taking the timing on boost down a lot of course but talking about the preboost area from 80 to 120.
