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Discussion Starter #1
hey guys, a couple of quick questions about my newly running milano:

1) Ignition timing--is there a performance setting for more power or is the stock setting the best? how about for smog testing? i played around with the timing on mine and went from knocking under load (lugging) to slightly retarded and then even more retarded where it is now because i have to get the smog test. i **think** that the current setting is the best for power/performance but not really sure. so where do you guys run your's?


2) so newly rebuilt tensioner and of course it's leaking already with 350 miles on it! arggggg! oh, well, just a slight leak out the piston rod, from under the rubber boot. but i just noticed at idle that the tensioner bobs back & forth as the engine idles--is that normal? i realize that it is probably just doing its job but i don't remember seeing it move so much until today. when i rev the engine even slightly, it tightens and stops the movement but still at idle it constantly moves a bit with the roughness of the idle. so just looking for reassurance that it's not about to slip and snap!

and as always, many thanks for your help & comments....loving this car the more i drive it and really amazed that you can buy milanos for $150-$1000 all day long! but i'm sure you all know this already.
 

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Hello,
I would not try to mess with the timing too much because from my experience you could possibly burn a valve or an electrode inside your distributor cap. Pull it off and check to see if any of the prongs are burnt, if not, set your timing back to factory if you can. Unless you have a modified brain unit that calls for timing advance, I would suggest to leave it untouched, then again I could be wrong. Someone may correct me on this, just never had any luck into obtaining a better running car. I have a modified ecu on mine, when it was running, I used to set it to spec on advance, I do not exactly recall how many degrees, but if you look on the balancer you have a few marking ahead of the Fissa, (top dead centre), you can measure one of those and calculate the same distance ahead to know exactly how many degrees advance you may want. A good trick to get your mixture and performance a little better than the factory, is to tap and install a Carb Jet into the return chamber of the pressure regulator, i can check and tell you what size if you want to try it.

As for the mechanical tensioner, replace it with either a 164 tensioner or a mechanical one, they give you no issues.
 

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Bob, please tell me you're using a timing light for this.

In any case, given that you're new to the car you should set it to stock (F mark on the pulley) to see where you're at. For one thing the CA smog guys are supposed to check timing when they test it, so if it's off too much either way they'll flunk you.

Once you've got it baselined you can try advancing the idle timing about 5 degrees for a bit more power. See Greg Gordon's L-Jet page for some info and other tune up tips. But I would start by setting it to stock and driving it for a while.
 

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set the timing to spec. if the cat is working you should pass.
if the rest is in a working state, good O2 etc. And no air leaks on under the hood etc.
 

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Discussion Starter #5
no timing light when i wrote this but found my roommate's and checked it out and it was still slightly advanced but pretty darn close so i backed it off just a bit and passed smog with flying colors! not even close. so happy as now i have my plates and knowledge that my car is working and set right where it should be. i feel like a proud parent whose kid just got into a great college!
 

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Obviously you should never use the " knocking, then back off a little" rule for setting timing. Not only does it usually screw something up, it sometimes will result in less power. too much advance will always loose power on a dyno in my experience with tuning. Also, advancing the timing until 'just' knocking can cause cylinder pressures to be very high at rev, and can cause inaudible detonation which will eventually melt the piston crown(s) or possibly fry the valves (it will also cause high emmissions)...

but...
the factory setting should pass smog no problems, and i found ON MY CAR that 11° BTDC @850 rpm gave an overall better power curve on a slightly hot 3.0L (dyno tested of course). gained a little low end but the upper band was pretty much the same. I think the factory spark advance module maxes out its curve at like 3 or 4 thousand revs ayways:rolleyes:. no need to exceed ~31° in high rev band either, as it seems to lower output and increase possibility of damage
 

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Discussion Starter #8
forgive me, alfa guys, as i grew up with VW 8v engines in which you gained a noticeable increase in power and throttle response by advancing the timing as far as you could. basically just below knocking. so i just have this built in my brain even though my current VW which is a 16v is not like this. but regardless, none of these vw engines will be damaged by advancing the timing. i never really thought any engine would be so perilously close to meltdown just by advancing the timing. **** italian cars!

anyways, used the timing light so i'm pretty close. i did back it off a bit to pass emissions but i will set it properly tomorrow. anyways, enjoying revving this engine to the redline each & every time i take off! just can't resist. ****, if i had a ferrari, i'd be in jail! (how do those dumb people drive their ferraris so slowly? money is wasted on the rich!)
 

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all engines can be damaged by detonation, especially mildly tuned Italian ones:p...

Its not just a little timing to screw things up, im talking LOTS...like id be worried about 18° at idle with factory Mgmt curve:D There is a point where an engine will make its best torque...by going less OR more you can loose out. These are things you would never know if the car was not put on a dyno.
 

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Discussion Starter #11
all engines can be damaged by detonation, especially mildly tuned Italian ones:p...

Its not just a little timing to screw things up, im talking LOTS...like id be worried about 18° at idle with factory Mgmt curve:D There is a point where an engine will make its best torque...by going less OR more you can loose out. These are things you would never know if the car was not put on a dyno.
well there is only a certain range that the engine will even run. and if you're not excessively advanced and hearing crazy knocking, i would think any normally aspirated engine would tolerate a bit of advance with no damage.

me thinks you guys are a bit too timing exaggerated! have you ever heard an american v8 going up a hill? and our compression ratio is only 9:1 so it's not like the engine is highly stressed. has anyone on this board ever ruined an engine thru excessive advancement? i doubt it. you would probably have to have it so far advanced that it wouldn't even run.
 

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If you can hear and know that is knock it is a good old school way of doing it.
in my manual for my 1968 Toyoda it says advance untill it pings one or two time when you wamp on it. And that motor lasted somewhere in the 1.5 to 2 million mile mark.

And as you were very close to spec. I would say you were right on the mark.
the problem is some motors will not knock at all in a way you can hear and it can't be set that way. I never had the 2.5 knock with its super low CR. but my 3L 'S' with its high CR will knock in the 1500-2000 range. I had to add extra spark retard in that range.
(programmable ECU VEMS)
 

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the type of 'knock' or 'detonation' which is typically responsible for damage in engines (esp. forced induction ones) is usually inaudible as its at the upper range of frequencies in the hearing range. This type of detonation does not sound like rattling coke cans and occurs at mid to upper rpm where there would generally be too much engine noise to even make it out.

...wouldn't worry about it too much if your use good gas tho
 

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Discussion Starter #14
anyone have any info on question #2 about the tensioner? or if you're too lazy to go up & check, here is the question again:

i just noticed at idle that the tensioner bobs back & forth as the engine idles--is that normal? i realize that it is probably just doing its job but i don't remember seeing it move so much until today. when i rev the engine even slightly, it tightens and stops the movement but still at idle it constantly moves a bit with the roughness of the idle. so just looking for reassurance that it's not about to slip and snap!

thanks
 

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What type is it? mine does not seem to move at all. I use the old oil filled type with the oil feed plunged. I don't think the newer thermo-crap type should be used at all. if you have the new type the main spring seems to like to snap. if you give the belt a good tug between the heads does it go slack? the only thing I have noticed is the belt seems to wonder back and forth on the pulleys a tiny bit but never to the point to touch anything.
 

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I just scrolled up and see it is a oil type did you remember the 'O' rings for the drane part?

there should be 2 'O' on the feed stud and one 'O' in the drane hole. the steel plate seems to be the only thing to hold that in place.
 

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(de) tensioner

at (hot) idle, there is little oil pressure, so my thoughts are that a slight bit of movement would be expected. Revving and thus the increase in oil pressure would understandably impact how the tensioner is able to control the proper tension. When cold the engine makes more oil pressure and has more friction and is contracted, and i believe* the de-tensioner is there to increase tension under these cold conditions...when hot it will lower the overall tension, as things warm and expand

* i have never read up on how exactly this thing works, but just an educated guess (my cars have home fabbed fixed tensioners)
 

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Discussion Starter #18
yup, all the proper O rings were installed as they should be. i read up on many threads about how and where each O ring goes and also about adding a bit of silicone. i feel confident that it was done properly but yet it leaks. oh, well, nothing to do at this point but sit and wait.

and brendan, i too think that the motion is probably ok and normal. i guess i was just hoping for reassurance since i figure it's an easy thing to check as long as you haven't installed the plastic timing belt covers. and i agree that the the oil pressure once revved tightens everything up like it should. i haven't actually observed it when cold so i'll check that when i can. and the belt is always tight. geez, i don't even understand how they could ever slip as when trying to install the belt, it is so tight that it's quite a struggle to even get it on the pulleys. seems like it would run all day with no tensioner at all and be fine but i know that ain't the case.
 

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why are people calling it a tensioner went it is a de-tensioner ,Its holds the belt inplace
at low rev and at hight revs it de-tensions the belt so it can move more freely.

On my the spring was snap and the bearing was sezed .
At the time I did the timing belt i had never dune one in my live .
I all new parts and so far so good 1year along all good.

cheers
 
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