# ignition timing? which way is which?



## Sleeper-Dub (Nov 27, 2008)

this is on a mk1 rabbit 1.8l jh engine
ok so my fly wheel only has 2 marks on it. i know the *o* is zero and the hash to the left is 6* btdc... which way do i need to go to make more horsepower? advance or retard? and which is left or right? right now i believe i am sitting at 12* btdc (to the left of zero)
picture time (I) is the 6* hash (o) is zero
.........*I*........*O*.......
<<<< advance?
or 
<<<< retard?
i read a honda forum cuz i couldnt find any good info here.... that was probly the my first problem







anyways tho it confused the hell out of me on what they were saying and now im scared that i either advanced it too far or retarded it too far....
advancing at idle makes the idle faster right? and retarding will make it want to knock correct?
i have a TT 272 cam, HD valve springs and i think my cam is retarded 4 deg. whats the max ignition timing i can run without blowing my motor up?


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## OLDSKOOLVWS (May 12, 2004)

*Re: ignition timing? which way is which? (Sleeper-Dub)*

You are correct. This picture shows zero degrees at the dimple.








The pointer on the trans case (right below the white dot / black line) is your alignment point.








Factory timing is 6 +/- 2 BTDC as indicated here off my 84 GTi.








On my 84 daily driver, I also have a 272 with HD springs and a bunch of other stuff to match with it. I currently run at 8 ATDC. It's good pulling power but you sacrifice gas mileage. You really need to adjust to your best interest though. If it's adjusted wrong you get flat spots in certain points of the RPM range or it just stumbles and runs poorly.
If you retard (BTDC) the explosion happens before the piston reaches the end of the stroke (double the work..sort of) and if you go ATDC it occurs after the stroke (less work).


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## OLDSKOOLVWS (May 12, 2004)

P.S. Advancing too far can cause you motor to go kaboom.


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## ejackson_5 (Jul 10, 2006)

*Re: (OLDSKOOLVWS)*

And go buy one of these:
http://www.harborfreight.com/c...40963


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## Cynical 1 (Jan 23, 2003)

*Re: ignition timing? which way is which? (OLDSKOOLVWS)*


_Quote, originally posted by *OLDSKOOLVWS* »_If you retard (BTDC) the explosion happens before the piston reaches the end of the stroke (double the work..sort of) and if you go ATDC it occurs after the stroke (less work).

you mean ADVANCE the timing. 
advanced means the plug fires before the piston reaches tdc (top dead center), retarding the timing means it fires at or after tdc. 
advanced is good for overall driving, just don't advance too much if you have no knock control, as if you advance too much you will get detonation/pinging and severely damage the enfgine. 
retarding timing may help in torque, but fuel mileage and emissions will suffer. 
start out about 8-10 degrees btdc. go drive it, and go from there. 
me, i'm 26 degrees static advance, but my valve timing is retarded (different topic).


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## chickenfriend (Jan 31, 2005)

*Re: ignition timing? which way is which? (OLDSKOOLVWS)*


_Quote, originally posted by *OLDSKOOLVWS* »_










Curious, did you shave those timing tool lugs down? I did the same to mine.


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## OLDSKOOLVWS (May 12, 2004)

*Re: ignition timing? which way is which? (Cynical 1)*


_Quote, originally posted by *Cynical 1* »_
you mean ADVANCE the timing. 
advanced means the plug fires before the piston reaches tdc (top dead center), retarding the timing means it fires at or after tdc. 
advanced is good for overall driving, just don't advance too much if you have no knock control, as if you advance too much you will get detonation/pinging and severely damage the enfgine. 
retarding timing may help in torque, but fuel mileage and emissions will suffer. 
start out about 8-10 degrees btdc. go drive it, and go from there. 
me, i'm 26 degrees static advance, but my valve timing is retarded (different topic). 

Yes, you are correct. The flame front reaches the piston sooner because the firing occurs sooner. Duh. That's what I sort of meant..I think.


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## jorge r (Apr 27, 2006)

*Re: ignition timing? which way is which? (Sleeper-Dub)*

Timing the ignition spark in relationship to the piston, and there is timing the valves in relationship to the piston. Two different things and should be kept seperate.
As the engine speed is increased, higher rpm, the ignition advance should also be increased, full advace should be 36 - 40 degrees BTDC. Proper ignition advance should not cause predetonation noise, no pinging. Pinging can also be caused by overheated combustion chambers and EGR helps cool them off, a faulty EGR system can cause pinging and should not be confused with too much ignition advance. If the igntion timing is not advance enough, horse power will not be optimized.








Valve timing, or camshaft timing, if the camshaft timing is advanced, or vavles open earlyer, it is in slow rpm mode, good vacuum and good for towing and fuel saving, top high rpm will become lower and with less power. 
Retarding the camshaft timing or cvalve timing will cause the valves to open later in relationship to piston TDC. This retarding will cause the power band of the engine RPM to be moved to higher rpm. Less power at low rpm and peak power at higher rpm.
For city driving, stop and go, stick to stock or your preference, not good to have the valve timing advance too far. For mostly highway driving, you can advance the valve timing a bit since engine will run at higher rpm. For racing, then run your engine at high rpm most of the time and advance your valves or the camshaft is designed already advanced.
http://www.hotrod.com/techarti....html


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## ziddey (Apr 16, 2006)

*Re: ignition timing? which way is which? (jorge r)*


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