what do you use for timing on your na sohc for performance? - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

tastyratz · 09-21-2005, 01:30 PM

ok so thats about it. Sohc base timing is 15 degrees. Dohc base timing is 20 degrees. Running several degrees advance is safe for the sohc and the dohc.... Usually ok to run a little more on any car really. These are same bottom ends (minus cooling oil squirters on dohc and knock sensor) but the dohc has higher compression. However, the dohc was tuned from the factory to run higher compression. My question is if you make power cranking the dohc to 22-23 degrees ignition advance, could you safely crank the sohc to 22-23 degrees and make more power by safely doing so? This is a 2-3 deg increase of timing for the dohc but thats a 7-8 deg advance over stock on the sohc

Would that be at all a good idea?? Do you have a SOHC thats currently in an NA build state, if you do how far have you found you could safely advance your timing? atleast till it stopped making power and just cause more stress. BTW my car is daily driven on 93 octane which is alot more than the sohc was originally tuned for from the factory. (Is there a rule of thumb for octane to advace i.e. 1 pt octane is good for .7 deg advance or however)

tastyratz · 09-26-2005, 01:12 PM

bump. come on you mean to say nobody here runs their sohc at other than stock settings? nobody can answer this??

s134 · 09-26-2005, 01:15 PM

hmmm... i would just try it.lol

s134 · 09-26-2005, 01:28 PM

Ok I asume he is talking about degrees after top dead center.... but unless he increases port timing by increasing valve duration or lift I don't think will really be able to make any more power I would say no more than 4-5 degrees on stock shit no power advantage.... he is asking is it safe when compressing atmoshpere you don't really have to worry at all the there is very little chance for real damage if the car spark knocks or predets then retard untill it does no longer do so.. The Idea is the fatory sets the timing up pretty well for the highest over all power through out the power bang and not just at peak because if you advance from 25 degrees of total advance to 27 and you gain a 2hp from 6600 to 6900 but loose 8ftlbs of torque and loose like 10hp from 1500 to 4000 you have done a bad thing.. even thought the dyno says you have mad more peak power but who the fuck cares about peak power anyway

09-21-2005, 01:30 PM	#1
tastyratz Zilvia Addict Join Date: Dec 2003 Location: nh Posts: 995 Trader Rating: (4) Feedback Score: 4 reviews	what do you use for timing on your na sohc for performance? ok so thats about it. Sohc base timing is 15 degrees. Dohc base timing is 20 degrees. Running several degrees advance is safe for the sohc and the dohc.... Usually ok to run a little more on any car really. These are same bottom ends (minus cooling oil squirters on dohc and knock sensor) but the dohc has higher compression. However, the dohc was tuned from the factory to run higher compression. My question is if you make power cranking the dohc to 22-23 degrees ignition advance, could you safely crank the sohc to 22-23 degrees and make more power by safely doing so? This is a 2-3 deg increase of timing for the dohc but thats a 7-8 deg advance over stock on the sohc Would that be at all a good idea?? Do you have a SOHC thats currently in an NA build state, if you do how far have you found you could safely advance your timing? atleast till it stopped making power and just cause more stress. BTW my car is daily driven on 93 octane which is alot more than the sohc was originally tuned for from the factory. (Is there a rule of thumb for octane to advace i.e. 1 pt octane is good for .7 deg advance or however) __________________

09-26-2005, 01:12 PM	#2
tastyratz Zilvia Addict Join Date: Dec 2003 Location: nh Posts: 995 Trader Rating: (4) Feedback Score: 4 reviews	bump. come on you mean to say nobody here runs their sohc at other than stock settings? nobody can answer this?? __________________

09-26-2005, 01:15 PM	#3
s134 Zilvia Addict Join Date: Jan 2005 Location: indianapolis, in Age: 40 Posts: 634 Trader Rating: (0) Feedback Score: 0 reviews	hmmm... i would just try it.lol __________________

09-26-2005, 01:28 PM	#4
s134 Zilvia Addict Join Date: Jan 2005 Location: indianapolis, in Age: 40 Posts: 634 Trader Rating: (0) Feedback Score: 0 reviews	Ok I asume he is talking about degrees after top dead center.... but unless he increases port timing by increasing valve duration or lift I don't think will really be able to make any more power I would say no more than 4-5 degrees on stock shit no power advantage.... he is asking is it safe when compressing atmoshpere you don't really have to worry at all the there is very little chance for real damage if the car spark knocks or predets then retard untill it does no longer do so.. The Idea is the fatory sets the timing up pretty well for the highest over all power through out the power bang and not just at peak because if you advance from 25 degrees of total advance to 27 and you gain a 2hp from 6600 to 6900 but loose 8ftlbs of torque and loose like 10hp from 1500 to 4000 you have done a bad thing.. even thought the dyno says you have mad more peak power but who the fuck cares about peak power anyway __________________