Ok I know theres probably already a thread on this but couldnt find it in search.

I would like to know the cheapest/easiest way to advance my ignition timing and what is a good range to set it. I have added more fuel with my SAFC with I think automatically retards timing so I want to put that timing back in.

 

you would have to rotate the crank angle sensor with a timing light. I would not recommend this on a turbo car as it is too imprecise. If you don't have the money for an Rtek 2.1 (which has adjustable timing control) you sure as hell don't have the money for a rebuild.

 

I agree with Aghx... But to answer your question.

Get a timing light, loosen the bolt on the Crank angle sensor (in the front of the motor with black cap) turn it clock-wise to advance it some. (maybe its counter-clock-wise?)

You'll want the marker on the front cover to be at the right of the marks on the main pulley. Marks are at 5 and 20 degrees ATDC (After Top Dead Center) To advance it you'll want to be at closer to TDC.

Good luck and I hope your not driving a turbo!

 

Im not driving a turbo. Am I correct in the assertion that since Im adding fuel I should advance timing to squeeze a bit more power out of it?

 

oh its also important to know whether to rotate the bolt on the crank angle sensor clockwise or counterclockwise for advance.

 

bump

 

Rotate clockwise to advance. If you rotate it while the car is running, you will be able to tell what the car likes and what it doesn't.

 

You just loosen it, turn it, tighten it carefully.

I did the math to get an idea of how much to advance it

Depending on your resolution, if I remember right abut this much if it shows right

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About 1/3rd a cm or alittle less should be 2-3 degree if I recall

No not more fuel, timing is when it ignites the fuel, retarded would be slower advance would be quicker, too advance and the fuel can detonate, pre mature ignition.

Correct me if im wrong guys

So if you advance it alittle more then stock, run higher fuel octane, I try to keep 89 in the tank, I don't have it enough advance that 87ish will knock but butt dyno agrees that 89 or some 91 does feel smoother then before, stock timing with 91 (or some octane booster) would result in slow take offs in low rpms, and high rpms would be like vtec kicked in, also tons of back firing. Now theres little back firing and the low end is still decent like stock.

Hope that helps, it's not really worth it :P

 

You have to ADD fuel to your N/a? What the hells wrong with it?

Run 87 top tier, don't really worry about your timing all that much. I'm really wanting to know why you're adding fuel to it.

 

way back in 2004, long before the days of the Rtek 2.1 , I had a 172rwhp s4 n/a with an SAFC. I had advanced the CAS significantly, at least 6-7 degrees. This added a little bit of power up top, but I couldn't figure out why it was running lean (high 13's AFR). I tried new secondary injectors and fuel pump, thinking that maybe I had maxed out the n/a fuel system.

Eventually I put the CAS back to stock, and it was pretty rich again, back in the 11's. Weird. At no point did I ever run more than 87 octane, even with the lean AFR and the advanced timing. I never detonated or had any problems with it.

 

Advancing the timing ignites the fuel earlier and allows more time for fuel to burn before the power cycle is over. It makes sense somewhat. You would figure the computer could compensate for that small change though.

 

i was surprised i had to add fuel too, but the dyno doesnt lie 13whp increase with the safc. so by me tricking the car with the safc to add more fuel does it automatically advance ignition timing?

 

bump

hello?

 

You sure your fuel filter isn't clogged? The stock engine runs fairly rich.

 

new fuel filter installed in december. my question has gone unanswered... since more fuel is being added does the car automatically advance timing? and if it does could it benefit from possibly more advance?

 

If I remember right, the S-AFC's way of tricking the ECU is by controlling the air flow meter's signal. Which when done, causes the ECU to advance the timing since it see's more air flow according to the AFM's signal which is how you get more fuel.

You could have gained that 13 whp just because of the advance in ignition timing rather than the addition of the fuel.


This is what made me sell my Safc 2. After finding that information and thinking about it more and more it was just stupid to trick the ECU in that kind of way, on a forced induction car that is. For instance, if your under a load and the Safc is set at more fuel the computer doesnt realize your under a heavy load and keeps advancing the timing which can and most likely will cause problems.

It's also my theory on why my buddies T2 just recently lost compression in the rear rotor a few weeks ago when the car ran perfectly fine up until that point.

I don't think it would hurt the N/A cars all that much if at all though.



Maybe try leaving fuel set stock and adjusting timing to see?


From the info i've seen about N/A's they never add fuel but take it away in the midrange I believe.

 

That makes a lot of sense. Maybe more gains could be realized if i actually leaned it out just a bit and manually adjusted ignition timing. I just went through my first full tank of gas after the tune and got 13mpg. WTF! thats what my buddys BMW M6 gets.

 

bump

 

Regardless the computer advances timing too.

If you adjust the timing alot, you need higher octane fuel. If you adjust it a few degrees, you'll gain a tad. On a n/a its okay to advance it a bit.

I'd stop dumping so much fuel in a already rich running car, advance timing a bit. It's n/a, your not gonna get some amazing amount of power out of it

 

13whp from the SAFC tuning is a 10% increase which is definitely noticeable.

 

I decided to be guinea pig (scary actually) and bumped my timing up 3 degrees. She actually runs better and idles better too. Still on 87 pump gas (with 10% ethanol).

 

nice. im still confused about where the CAS is. is it the box where the ignition wires run to up in the front of the engine bay?

 

CAS on my pollen covered S5 with S4 front cover.

 

See nut on the stud in the above image? It'll have a black cap on it if you have never had the engine rebuilt or cas replaced. The only way to get it off is to break it. It is a tamper seal so it doesn't need or have to be there.