Rep Power: 0

Is there a way to Advance the timing on our civics? I understand this would raise the compression ratio due to the slightly increased stroke?

 
Rep Power: 401

advancing timing won't change your compression ratio. it simply changes the time during the cycle when valves open/close, allowing for better filling of the combustion chamber and/or scavaging.

 
Rep Power: 0

Then why do people say premium fuel is req'd if you advance he timing? I thought advancing the ignition timing (thru the distributor) like i did on my old accord... changed when the spark ignited the combustion chamber thus requiring a retarded detonation of the fuel hence 91 octane.. and can this be done on our cars?

 
Rep Power: 401

Ah yes, you're talking ignition timing, when I was talking cam timing.


Okay..... Yes, you're right ignition timing is when the spark ignites the compressed air/fuel mixture...

Let’s see if I can explain this well enough.

The advancing of ignition timing can cause detonation, which is why it’s best to be on higher octane pump gas. Also, higher compression in the combustion chamber also calls for higher octane pump gas. As you can tell, the higher the octane, the more resistant the fuel will be to resisting detonation.

Most cars have an ignition curve programmed as such, that it is conservative enough it will not cause detonation. However, if you use a higher octane gas, you can advance your timing a bit to gain a bit more power.

Also, do note that as the rpm goes up, the ignition timing becomes more advanced. This is because the piston is moving at a higher rate of speed, and in order to keep the timing right, the ignition is sparked a bit earlier.

 
Rep Power: 0

Sorry to sound mean bro but you still didnt answer my other question... can it be done to our cars since we have no distributor? If so, how? And is it safe? And am I correct when i say that advancing the ignition timing in turn raises the compression ratio due to a longer stroke?

 
Rep Power: 401

you know, i'm not sure on the advancing of the timing without a distributor. that means it'd have to be done electronically by some type of ECU. I don't know if such a thing exists, but if you ask around on the site, you should be able to find out. And it would be just as safe as with any car... meaning you'd be best off putting it on a dyno to do the timing adjustments. But I wouldn't advance it more than a few degrees (2 or 3 at MOST) on a stock ignition system.

As for advancing ignition timing, NO this does NOT change your compression ratio. All ignition timing does is change the time at which the spark plug fires and causes the combustion to occur. Ignition timing doesn't affect stroke.... the only thing that changes stroke is the crank shaft.

 
Rep Power: 0

But thats what ignition timing does... it changes the time the fuel ignites.. it delays it...and because of this, the piston travels up the chamber further before it ignites creating a stronger explosion because it compressed the fuel/air more... wouldnt that be a longer stroke?

 
Rep Power: 401

If you advance timing, that doesn't DELAY it... it does the exact opposite. But in all honesty, when you talk of advancing or retarding (which would be delay) timing, you are talking of a MERE 100ths or 1000ths of a second. Your compression ratio is calculated by combustion volume at BDC vs combustion volume at TDC. So, again... no, it won't change your compression. And the 1000th's of a second difference you make in advancing or retarding timing won't make your compression different either. Changing the timing has an effect on the WAY the air/fuel burns, making it burn more evenly, giving you just a tad bit more power. That is where ignition timing is getting the power from.... by manipulating the ignition timing curve, you can get more even burning of the mixture, and have the spark come at a better time during the compression stroke.

 
Rep Power: 0

check with Hondata. they might have a product that suits your needs. I wouldn't mind having the ability to manipulate my ignition timing but one would definitely need some type of piggy-back system to alter the parameters of the factory-programmed ECU.