Hi, this is an easy question, when you put adjustable cam gears to a SOHC or DOHC, when you going to give some advanced or retard degrees, you loose the bolts that fix the cam gear, but then do you turn the camshaft so you moved slightly the valves open-closed position? Or do you moved the crankshaft so you left the camshaft and the valves at same position, but instead you moved up or down the pistons???

 

You loosen the 5 bolts on the cam gear and rotate the center. You don't loosen any other bolts and you should not be rotating the the entire motor (crank, timing belt). You're only rotating the camshaft.

 

Yes, I know it. But I have this concern, what if once you have the cam gear loosen, what if you instead of moving the center of it while the crankshaft remains fixed... what happens if you put the car on a jack, and move the crankshaft so the timing belt will move the outer case of the cam gear, so you are keeping the camshaft fixed, but the piston is going slightly up or down, I mean is there any physic or engineering diference about moving the camshaft (valves) while the crankshaft is fixed vs. moving the crankshaft (pistons) while the camshaft is fixed???

What actually I want to know is what could happens by engineering facts if you move the crankshaft instead of the camshaft???


Note: Like I already know, that my concern will not going to be understanding, I will upload a short video, of what I am asking here.




Thanks.

 

Moving the crankshaft would cause a greater affect. I believe that the ration is like 2 to 1. Also this would cause the balance shaft and oil pump to move as well.

I do not know why you would want to adjust the crankshaft timing when the purpose of cam gears is to make more or less cam overlap to shift the power band a little. Not simply change the entire timing of the car.

 

Moving the crankshaft while the cam and cam gear is fixed will give you the same effect as moving the cam gear while the crank and everything else is fixed. You're still moving that cam gear around and still retarding or advancing the cam.

Honestly, moving the crank around just to adjust the cam is more work then just rotating the cam gear.

 

That's exactly what I thought, but even that is true that is more work to turn the crankshaft, please read the quoted reply below, to understand why it maybe could worth the more work.

That about the ratio 2 to 1, is really interesting, maybe that's why I experiment the next behaviour:

Several months ago, I started to play with the cam gear, and I first set it to some advanced degrees moving the camshaft (normal procedure), and when I from first gear at 3,000rpm then I went 100% open throttle I notice a good improvement in acceleration and throttle response, it pull very well the first, second and third gear, but at fourth, goes down the power (like it was expected when advancing); then I tried retarding some degrees with same moving the camshaft procedure, and like it was expected, from first gear at 3,000rpm to 100% open throttle response it's turned a little more laggy and a little more heavy, less aggresive, then first gear suck, second was good, and third good, but at fourth gear it generates more top end power, ok, that's normally expected when turning the camshaft. (I personally loves more the torque and an agressive acceleration).

But after that, same day, I then, take the risk to set everything again to 0degrees, and readjust the cam gear again, but this time moving the crankshaft backwards, so, the cam gear outer case and the timing belt moves also back, but since the cam gear inner center remain at the same position it's looks like it is was advanced; I adjust it to same degrees that with previous tests, (I was not really sure, if I advanced or retard,) but this time with the crankshaft procedure, then when I was at first gear at 3,000rpm and I just go 100% full throttle, THE ENGINE WAS TRANSFORMED INTO A BEAST!!! For some reason (that's what I am trying to investigate, and that about ratio 2 to 1 sounds interesting) moving the crankshaft it gives me more power and torque through the entire 1 to 4gears, than when I was trying adjust it moving the camshaft...

BUT WHY???

 

Sorry for the bad English, it was a very hot Sunday afternoon at 90F degrees with a very high level of humidity Also the talk lines, were just improvised. Thanks.

SOME CRAZY BLOOPERS AT THE 11:24 minute till the end of the video.

Please feel free to comment, and critics as well.

 

Well actually after all is does not occurs the same engineering effect to move the camshaft vs. moving the crankshaft when adjusting the cam gears; because when you move the camshaft (normal procedure of adjusting cam gears), you are changing the time when the valves open and closed, you are not changing it's lifting duration (like an aftermarket camshaft lobes will do), but you are changing the degrees time when the valves will going to open and close, so if you advanced the cam gear degrees then you are changing the degrees time when the valves will open at, so the valves will now open early, but it will take same lifted duration, so now they will going to close early too. In the other hand, if you retard the cam gear, you are delaying the degrees time when the valves will open, it will take same lifted duration, but they will also being closed with some delay to it's previous settings.

Ok, but if you instead of moving the camshaft, for adjusting the cam gears, you instead, move the crankshaft then, you are changing the heights of the piston, and then you are eventually changing the ignition timming, because if the piston will reach TDC earlier or belated then the spark plug will going to ignited earlier or belated just when the piston reach TDC if earlier or if delayed; so moving the crankshaft will directly have an effect on the ignition timming; but the camshaft will only have an effect of the degrees time when the valves will going to being opened and closed, not when the spark plug will going to be ignited.

So, it is absolutely irrefutable then, that is not the same, and it will not going to take the same physics or engineering effect to adjust an adjustable cam gear moving the camshaft, vs. moving the crankshaft...

...then, this now, can explain why when I did the normal procedure moving the camshaft my engine power doesn't matter if I advanced or retarded didn't make significatly diference in power, cause I was not having more air into the combustion chamber (like an aftermarket camshaft will allow), but I was only changing the degrees time when the valves open and closed but as my car is SOHC I will not going to see so much improvements, like a DOHC could see. By the other hand, when I moved the crankshasft instead of the camshaft, then advancing it I noticed a lot of improvement and more power and torque output, due that I was advancing the ignition timming, making the combustion time more agressively due that the spark plug will going to ignited nearest to TDC piston height, but that was at naturally aspirated; now that I am turbocharged it will be a higher risk to have the ignition timming advanced cuase the risk of detonation or pre-ignition increases; so, now, I will better retard the crankshaft some degrees, so the piston height where the spark plug will going to ignited, it will being sligltly changed after TDC not before, that will of course reduce a little of power HP ouput, but it will allow the engine to run safer, and to use more boost to compesate the HP loss, than if the ignition timming were advanced.

Thanks a lot.

Note: Please noted that any swear or prohibited words had been used in this reply; all this content is a personal opinion, and does not necessarely represent the opinions of any other members than Jos_iQRacingEVO, so if you read it, and your don't agree with this information, you are at your freedom of that right; but also you have to respect my opinion, no one and I am not forcing in any way to anyone to follow, believe or try this information in any aspect of it; I the O.P. only believe in this info. I am the only who tried this at my own car, by myself with totally freedom. If you don't even like this info. then ignore it completely.

 

It's like me punching you in the face versus your face blocking my punch. Both do the same effect.

Your still only changing the adv or retard either way. One way is just much easier because moving the cams you can dial in more exactly. Another reason you don't move the crank is because now your moving the balance shaft and oil pump timing.
Save yourself the headache and adjust with your cam gears. There is no hidden magic horepower with adjusting via your crankshaft.

 

Exactly all this is simply an opinion until you provide solid data through back to back dyno runs.

I changed timing a little on a friends car (through ecuflash). It felt better on the but dyno than the previous timing did. Look at the dyno sheets and the car lost power...

Come back with facts. All of the conjecture gets old. This thread should also be in the Lancer section. When I first responded I did not even look to see that you are adjusting a SOHC instead of a DOHC car.

You need to tune via ecuflash or something similar to make the most out of your mods.

 

Moved to lancer tech

 

I agree with your above action. Thanks.

 

Dude you need to study basic mechanics before tackling this stuff if your asking this question. The standard 4 stroke engine has a rotation ratio of 2:1 with the crank spinning twice for every 1 revolution of the cam shaft. This is because there are 4 cycles: Intake, compression, power, exhaust.

The first downstroke draws in the air/fuel charge (intake)

the first upstroke compresses the charge (compression)

right before the spark plug fires to ignite the compressed charge (power)

forcing the piston into its second downstroke, then the second upstroke and final cycle expells the used charge completing the cycle and then its starts all over again.

 

/facepalm i wish they would ban this guy.