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View Full Version : how much base timing


Mr overkill
10-13-2007, 08:03 PM
what the timing people run for our cars when running 15 psi or more or is it stock (just wanna make sure )
Speedeuphoria
10-13-2007, 08:47 PM
prob depends on which head you have
boost geek
10-13-2007, 08:49 PM
I run 16 degrees on a G head at 20 psi.
turbovanmanČ
10-13-2007, 08:49 PM
Way too many variables. Best thing is to set it at 12 deg and do a run. If no knock, then advance 2 deg, if go faster with all other stuff being equal, IE 60ft times etc, and no knock, go another 2 deg. Stop when you hear knock or slow down.
Mr overkill
10-13-2007, 10:08 PM
ahhhh


will advancing it make the egts go up or down is nothing else were to change
Speedeuphoria
10-13-2007, 10:44 PM
more timing = less EGT
turbovanmanČ
10-13-2007, 10:49 PM
ahhhh


will advancing it make the egts go up or down is nothing else were to change

I can never remember this but I believe using theory, advancing the timing will raise EGT's, as I remember when breaking in small block chevy's, you retard the timing to stop the exhaust manifolds from glowing red hot and overheating.
Speedeuphoria
10-13-2007, 11:53 PM
nope read my post, more advanced lowers EGT's, thats why its a balancing act between EGT's and knock. Mostly on lower octane fuels like pump gas. So basically you run the timing till it pings, then back off a little, watch EGT's if there too high you will have to lower the boost cause thats the best you can do on that octane fuel

thats why a 2 step w/ timing retard will spool in neutral(or clutch in for a 5spd). Retarding the timing moves some of the combustion energy to the exhaust mani to spool the turbo.
turbovanmanČ
10-13-2007, 11:57 PM
nope read my post, more advanced lowers EGT's, thats why its a balancing act between EGT's and knock. Mostly on lower octane fuels like pump gas. So basically you run the timing till it pings, then back off a little, watch EGT's if there too high you will have to lower the boost cause thats the best you can do on that octane fuel

thats why a 2 step w/ timing retard will spool in neutral(or clutch in for a 5spd). Retarding the timing moves some of the combustion energy to the exhaust mani to spool the turbo.


Thats weird as retarding it for the SBC's lowers the exhaust temps????? but I do realize that retarding the timing starts the process later in the combustion process.