How much PSI before Timing has to be retarded?

[jmwenick]

I am just starting to peice my turbo setup together, and was wondering at what PSI do we have to retard timing? I have a .60/.48 T3 Thanks

[:: orion ::]

It' more of a HP level than a PSI...so call it 200rwhp is safe with stock ignition timing (~4psi form a T3/T4)...any more power than that, and you need to start retarding the base.

Half a degree for each pound of boost over 4 is a good, safe rule of thumb...but since you're using a smaller turbo...you could start retarding based on that formula at 6psi.

- Brian

[AZhitman]

I have been wondering this as well, and have gotten SEVERAL different answers.

I had my base timing set at 20 deg advanced frior to adding boost. Now I've added the IAP kit, max boost of 7-8 psi, and I was told by some to pull the timing back to 15 degrees advance, others said leave it alone.

I'm under the impression that the ECU will pull tioming if it needs to, and that manually retarding the timing is useless (and kills power).

Brian, love to hear your (and Ryan's) thoughts on this.

[Craving4Boost]

it depends are you running 93 octane or 91...i only have 91 in CA so i would not risk running norma timing even with a low 8psi. at least a couple degrees should do you fine.

[DammitBobby]

93 octane 10psi boost and 20 degrees timing. The theory that I have read is anything over 8psi and you need to retard your base timing .5 degrees per pound over 8.

[wannawangan]

Just the question I was about to ask. You beat me to it! Brian, thanks for the info. Now I have a starting point prior to tuning!

[jmwenick]

Awesome guys, thanks for the quick answers. I can't wait to boost!! I have 93 octane here and an internal wastegate that I beleive is set at either 6psi or 8 psi. Not sure yet. hehe. So I think I will leave the timing alone for now. Also, can anyone verify if the ecu pulls timing if I wanted to push it to 10?

[C-Kwik]

Keep in mind the method in which you increase fuel. Particularly with piggy-backs. AS they are typically designed to lower injector duty cysles of larger injectors by scaling down the MAF signal, the ECU will think the load is lighter and bump up the timing. As a result, you may actually have to pull some timing even for lower boost applications. At 6.5 PSI I did hear some light detonation on my KA in hot weather. I was using an E-Manage with 370cc injectors.

As far as the ECU pulling timing according to boost, no. The ECU has no idea that you are boosting. It will read more airflow so if that warrants some timing retard according to it's mapping, then it will. But there are a lot of factors that would go into that and the timing retard would be based on a NA motor's typical mapping. It may not be aggressive enough.

[Craving4Boost]

unless hes one of the lucky ones where the ecu automatically pulls timing during boost

[Jookmasta]

definitely with that size turbo, retard timing to around 15 when ur at like 12 psi cuz thats what i did. lol. i know of someone who ran the same turbo as you and had his timing at 18 or 19 when he was running i think 14 psi and his motor called it quits in about 2 months after being turbo. timing WILL kill ur engine. u will make more power with less retarded timing, but is the extra 20 hp worth blowin ur engine?