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Discussion Starter · #1 ·
Finally got a timing gun onto my 1.6 the other day.
It's been running very well.. feeling extremely fast.
Anywho.. since refitting the cas i never had a chance to check the timing.
Anywho.. this and the fact i couldnt get idle lower than just over 1k suggested the timing was quite advanced.
So... 28deg before top dead centre.
I cant hear any funnies happening though i've not put det cans on it yet, but mel drove it the other day and commented on how well it pulls.
Think I have some experimenting to do

I'm guessing this is far too advanced and i'd probably find more power still by pulling the timing back to something more realistic.
 

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I run loads of timing the second I split from idle but I've full control (I take it you are on the stock ECU again?). My idle timing is set to 16*BTDC and advances up to 30degBTDC the second the throttle is hit. For me, In vacuum, I just tuned until the car cruised nicely with minimal throttle input. My figures get high, but the engine runs great so I can't complain.

I wish I could see all the engines spark tables in one neat location on the internet. I'd make ignition tuning a whole lot easier
 

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Discussion Starter · #3 ·
yeah im on a standard ecu for now.
I dont know what map that has on it but i should think it does a fairly basic job at doing the same as you have done.. but probably not quite as far advanced.
 

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Make sure the timing mark on the pulley that you are referencing is the real timing mark. My pulley has various notches and nicks/marks around the edge. The wrong one was highlighted with white paint by a previous owner.

Drop the dipstick down #1 spark plug hole and find TDC. Then mark the notch on the pulley that seems to fall in line with zero degree marker on the teeth above the pulley.
 

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Good point niggle.

FWIW on my old engine I managed to induce knock whilst n/a with too much timing, so be aware
I'm running 18 deg with Tesco Finest Petroleum Spirit (99 RON). It's OK at the moment but I am prepared to wind it back if/when the warmer weather arrives. I have marked the CAS and camshaft housings for 18, 16 and 14 deg.

Incidentally, how do you measure 28 deg when the timing marks only go up to 18?
 

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Discussion Starter · #7 ·
well its a rough guess at how much further around the mark is.
Its almost totally vertical.

I have 2 marks (which I guess is right for the 1.6). I'd assume 1 is tdc and the other 10deg before ?
 

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I have 2 marks (which I guess is right for the 1.6)?
From what I can tell, only '94 models had both a yellow and a white timing mark 10 degrees apart. All others have a single (white?) timing mark on the pulley. It would be worthwhile establishing a proper TDC timing mark referenced from the piston TDC for two reasons:

1. In case the front pulley on your engine is not the original one
2. In case the outer part of the pulley has slipped around the inner boss
 

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Discussion Starter · #9 ·
yup i think i should do this actually though i do know for sure the timing is well advanced due to the fact i cant get the idle down any further.
 

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yup i think i should do this actually though i do know for sure the timing is well advanced due to the fact i cant get the idle down any further.
Yes, I can't get mine down to the "official" 850RPM either. It jumps to over 900RPM when I bridge TEN and GND in the diag. socket. The base idle screw is screwed right in and I have no vacuum leaks.
 

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I don't really understand Skuzzle mate.

You've put a thread up on timing but you don't actually know what timing your running and you don't actually know if your getting knock.

This is on the stock ECU right?

If so wind it back to 14?, there's absolutely no gain from running it THAT advanced and only possible downsides (knock).

Get off ya arse and get that TDC point marked out.


It is well worth doing as i was running the wrong timing for a while simply because i assumed the mark i was setting my timing against as TDC


Cheers
Mark
 

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Discussion Starter · #12 ·
I don't really understand Skuzzle mate.

You've put a thread up on timing but you don't actually know what timing your running and you don't actually know if your getting knock.

This is on the stock ECU right?

If so wind it back to 14?, there's absolutely no gain from running it THAT advanced and only possible downsides (knock).

Get off ya arse and get that TDC point marked out.


It is well worth doing as i was running the wrong timing for a while simply because i assumed the mark i was setting my timing against as TDC


Cheers
Mark
Yup Mark, stock ecu at the moment. I'm pretty sure the marks on the crank i was using were the right ones but i'll double check and by looking at the scale and working out how much past the scale im at i would say i am about 28 deg btdc.

Also, the car does feel very lively. The top end may be a little asthmatic but mid range is incredible.

I'll have to get some det cans on it i recon to check for knock.

Really this is just an excersize in timing and to see what peoples views are. My own view is that even 14deg is pretty tame with the quality of fuel we have now compared to what it was when the cars were first built. But I want input from others who have tried as to whether pulling the timing back nearer to 14 deg will actually gain me better performance.
 

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Thing is though on the stock ECU our only moving the timing curve around the rpm range, you not really gaining anything.

As niggle says,
Remove #1 spark plug
Stick the oil dip stick in
Manually turn the motor over till your sure you've reached TDC.
Check the timing make on the crank pulley is at the top.

If you remember from my post a while ago, with faffing about swapping motors and crank pulleys, i was setting the timing using a completely non stock dent/scratch on the timing pulley.

I was faffing around for around 3 months wondering why i couldn't get rid of knock.
Turns out i was running around 28?


Cheers
Mark
 

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IIRC early 1.6's only have one timing mark not two like the 1.8, as above you need to check TDC as a worn hamonic balancer may have let the timing mark slip!
 

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P.S. Perhaps the second mark has been made by someone re-marking TDC!
 

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My own view is that even 14deg is pretty tame with the quality of fuel we have now compared to what it was when the cars were first built. But I want input from others who have tried as to whether pulling the timing back nearer to 14 deg will actually gain me better performance.
Soz in advance for jumping in here - given that 99 RON is available at the pumps, would it be safe (knock wise) to run a 1.6 with an M45 SC at 5-6 psi on a stock ECU/injectors with the base timing set at 16 deg BTDC?
 

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No, without something to pull your timing under boost such as a Bipes or an intercooler/charge cooler to lower your intake temps, you should be running 6-8 deg BTDC as Jackson advise! Different setups/engines can yield different results, best start from the best known safe place and work from there!
 

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No, without something to pull your timing under boost such as a Bipes or an intercooler/charge cooler to lower your intake temps, you should be running 6-8 deg BTDC in Jackson advise! Different setups/engines can yield different results, best start from the best known safe place and work from there!
Gotcha...........thanks Rich
 
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