timing question

[AN89HATCH]

when you guys say retard the timing, you guys are talking about the base timing rite? last time i got a smog, it says my timing is 17 btdc, is this to much timing to run with 6lbs of boost and if so how much timing should i retard? this is a sohc ka

[klattr1]

retarding base timing is just a different way to do it but its not the best option as far as driveability goes. Orion would know more about this than me since he's ran with retarded base timing before on stock ka ignition map.With my JWT ecu, i get 14-16 degrees total timing WOT and im sure thats somewhat conservative for pump gas.

[:: orion ::]

~17 degrees base is too much IMO...unless you're running SUPER rich, like 9:1 A/F or lower.

Base timing on a SOHC is 15, and they have 8.6:1 compression...that's already turbo friendly.

For only 6psi, I'd leave it at stock, or maybe 1 degree retarded.

So knock it back a couple degrees to stock base, and you should be OK.

- Brian

[AN89HATCH]

hmm im still alittle confused, orion do you have aim? if so can you please aim me at supra1on1 i have some questions thanks

[AN89HATCH]

so is retarding the base timing different than retarding timing? can some one aim me that knows about timing, and the ka turbos thanks

[klattr1]

ill hit u up on AIM.

[AN89HATCH]

thanks!:) :ylsuper

[:: orion ::]

Yes...base timing is a static value that the ECU uses to make all it's other timing changes on.

So 20* for the DOHC, 15* for the SOHC.

Then the ECU adds or subtracts as needed for RPM and load, and that's the total timing.

i.e. under highway cruising, a DOHC will see 18-20* of advance, so that's 38-40* of total timing.

Under heavy load, it might only give 5-6* advance, so 25-26 total timing.

- - - - -

Now, say you are running a SOHC with a turbo...15* base timing.

If you change that base timing by any amount, it changes the total timing ACROSS THE BOARD. So under load and high rpm, the timing is more safe for a turbo car.

1-3 degrees of base retard is OK, but any more and you start to lose driveability and response, b/c off boost, the timing is so far retarded (this is what "klattr1" was referring to)...

Hope that helps - Brian