I have a question About adjusting the timing tables on a turbo car. since the turbo is doing nothing until 3000rpm. do I need to touch the tables below 3000rpm where are the places that that tend to need the most attention? thanks in advance for your help,this is my first post on here.

 

ive heard some people advance the timing at lower rpm to spool the turbo faster, but i dont know the details.

 

Remember that the table is referenced vs RPM and Gr/Cyl - just because you are at a certain rpm doesn't mean you need to adjust all the timing for that rpm point.

Take a look at your log files when you hit boost and see where your g/cyl are - my guess is that they will be at 0.5-0.6 or higher - this is a level you will never see before the turbo spools - so you can safely keep your timing stock or higher for each g/cyl point where you aren't in boost. (Though even before boost your VE will be kicked up by the turbo which is still pre-compressing the air for the motor - just not at a greater rate than the motor demands it - but it is still doing it more effeciently)

 

cool, thanks guys anyone else have any suggestions?

 

yeah, what Chris B. said.. I was recommended not to start reducing timing before 3200RPM and .72 gm/sec window

 

I am new to tuning FI on Ls1's... as i have never personally done it... but the theories still hold the same.. on my mustang i ran real low base timing.. 3 degrees versus factory 8-10 degrees. This is called doping(produces more heat in the exhaust) and worked really well to spool the turbo up. Lag was almost non-existent with the timing low... but when i cranked it up to 10 degrees initial.... lag city.

 

That's odd . . . I have heard the exact opposite. Why do people keep timing high as the turbos are spooling up then, everything I have heard is that it helps to spool the turbos.

- Dug