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View Full Version : timing at peak tq!



ranz
11-23-2010, 05:56 AM
i read a couple of threads talking about time advance at peak tq, and some were hinting to lower the timing during spool and peak tq with richnen it a bit so it can build heat to spool better and increase ur peak tq numbers. the thing which is not clear is by how much one should lower his timing for best result. or is it trial and check(which is the case i guess).

is 5 degree at peak TQ considered too much on my setup (check sig) with 33-34 psi on 93 oct although i dont have knock even i add 1 or 2 degrees?

Reese Tuning
11-23-2010, 11:25 AM
I would say 5* is about right where it should be. Keep adding and watch the knock voltages.

Â* Â*James

ranz
11-23-2010, 03:45 PM
even if it let me add some timing dont you think i will be losing some tq if i add more timing?

tabio42
11-23-2010, 04:43 PM
If octane were not a factor - Once you have found the ideal timing at a given RPM/load, adding more timing will result in diminishing or negative returns to torque levels. But it is hard to figure that out without a dyno... unless you have the buttdyno 4000SX :)

Or you could try to use your A/F ratio to check and see how much fuel the engine is consuming at different timing advance values.

ranz
11-24-2010, 10:44 AM
octane is always a factor on 93.lol!
i guess going on increasing timing till knock, i will lose the some tq at this high advance timing at spool.

oldevodude
11-26-2010, 05:43 PM
odds are You might even gain torque O0

biggiesacks
01-18-2011, 01:13 PM
Its going to be a wash rinse repeat process to really get it nailed down. If you use a Virtual dyno program it will help you see gains and losses, just make sure your on a flat road. In my experience with my evo 8 dropping the timing in the spool area, lean spool disabled of course, helped. Not alot of timing just a degree or maybe 2. Anything more then that made the actual acceleration of the car laggy (turbo spools at lower RPM but it takes alot longer to get to that rpm negating any improvements). All evo's are a little different, i guess esp with the 8's as the QC on the head casting doesnt seem to have been as good as the 9's. On 93 i would expect it to knock before you get into blow your engine up territory, but i wouldnt take that for granted, just make small changes and try and be as consistant run to run as possible (gear and RPM you start the pull on). I also like to try and work on spool in higher RPM's not just the 2-3k range.