ok so i got the hang of airboys spread sheet and im helping my friend tune his 06 wrx
runs on 93 all the time btw
just a stage 1 but he wants more power
right now i got gabedudes stage1 in it with some more boost to make him happy
i havn't touched the timing but i get the idea

i should add more timing (advance so the base timing number should go higher) so the actual fuel/air ignition happens just after tdc

i think thats rite please tell me if im wrong don't feel like blowing anything up

how much timing should i add though ? right now at 6000rpm base timing is at 11.64 degrees btdc would i go up by 1 degree to 12.64 degrees btdc or only .5 and when i log i should be watching his kc and if it goes above the 5.98 (what the timing advance max is) then start pulling the timing (retard)


again school me, if im wrong tell me but tell me why and what i should do diffrently

thanks for any help

It sounds like you're pretty new to tuning. To have a fighting chance of tuning an engine without blowing it up, there's pretty much no way around having to buy a couple of books and spend some time reading them. I'd suggest Engine Management: Advanced Tuning by Greg Banish and How to Tune and Modify Engine Management Systems by Jeff Hartman as a place to start.

Seriously, there's a lot of basic knowledge about how the parts all interact that you need to be fluent on before you can safely make any changes.

EDIT: BTW, not saying I'm an expert. I made the suggestion because I'm just a little ways ahead of you and I had to recently learn all this stuff myself and those books were helpful to me.

I'm going out to buy those tomorrow :)

Actually that map could use leaning out more than adding in more timing. That is what I do for most 06-07 WRXs that I tune using that map to start with. You should invest in a WBO2 and the books mentioned above first. Learning how to tune on a turbo car can be bad. There are many things you have to watch out for and understand about EFI and more specifics about the Subaru ECU. It would be better to start with a NA car.

i somewhat understand the principals (mostly from my bike which has a very stupid efi in it) but just the way subaru does everything confuses the **** out of me lol
like with the timing i know you want the spark to happen slight before tdc i thought i remember reading somewhere 20 degrees is a good start but i also know that you want the explosion to actually happen right when the piston starts in to the down stroke (power stroke) too soon and the you get detonation (knock) to late and your not utilizing the mixture as well as you can
but thanks i'll be getting a wb02 shortly got an overtime check lol

i somewhat understand the principals (mostly from my bike which has a very stupid efi in it) but just the way subaru does everything confuses the **** out of me lol
like with the timing i know you want the spark to happen slight before tdc i thought i remember reading somewhere 20 degrees is a good start but i also know that you want the explosion to actually happen right when the piston starts in to the down stroke (power stroke) too soon and the you get detonation (knock) to late and your not utilizing the mixture as well as you can
but thanks i'll be getting a wb02 shortly got an overtime check lol

Actually, you don't want the "explosion" to happen at TDC. You want peak cylinder pressure (PCP) at 15*ATDC. Because the "explosion" is actually a deflagration, it takes a while for the totality of the charge to be ignited. To get PCP to occur at 15*ATDC, you need to light the charge BTDC. The time it takes from spark to PCP is dependent on a BUNCH of things like charge temp, AFR, pressure, density, fuel composition, etc. Then RPM complicates it because for a given time in milliseconds, the number of degrees changes with RPM (i.e. 10*@2000RPM is the same duration as 20*@4000RPM). That's why the map isn't level, or even planar.

Actually, you don't want the "explosion" to happen at TDC. You want peak cylinder pressure (PCP) at 15*ATDC. Because the "explosion" is actually a deflagration, it takes a while for the totality of the charge to be ignited. To get PCP to occur at 15*ATDC, you need to light the charge BTDC. The time it takes from spark to PCP is dependent on a BUNCH of things like charge temp, AFR, pressure, density, fuel composition, etc. Then RPM complicates it because for a given time in milliseconds, the number of degrees changes with RPM (i.e. 10*@2000RPM is the same duration as 20*@4000RPM). That's why the map isn't level, or even planar.

any idea on how to detemine if you are hitting this magical 15 degrees?

Dyno. Rock timing back and forth until you find peak torque. Otherwise, drill and tap the block for in-cylinder pressure transducers.

In the real world, you'll never manage to even get close to 15*ATDC on pump gas.

Actually, you don't want the "explosion" to happen at TDC. You want peak cylinder pressure (PCP) at 15*ATDC. Because the "explosion" is actually a deflagration, it takes a while for the totality of the charge to be ignited. To get PCP to occur at 15*ATDC, you need to light the charge BTDC. The time it takes from spark to PCP is dependent on a BUNCH of things like charge temp, AFR, pressure, density, fuel composition, etc. Then RPM complicates it because for a given time in milliseconds, the number of degrees changes with RPM (i.e. 10*@2000RPM is the same duration as 20*@4000RPM). That's why the map isn't level, or even planar.

i didn't say the explosion should happen at tdc i said it should happen atdc but because the explosion takes time that the spark should be btdc (like you said)


i know you want the spark to happen slight before tdc i thought i remember reading somewhere 20 degrees is a good start but i also know that you want the explosion to actually happen right when the piston starts in to the down stroke (power stroke) too soon and the you get detonation (knock) to late and your not utilizing the mixture as well as you can

Dyno. Rock timing back and forth until you find peak torque. Otherwise, drill and tap the block for in-cylinder pressure transducers.

In the real world, you'll never manage to even get close to 15*ATDC on pump gas.

Well, at least not at mid-high RPM's.