akauf at this point my brain is a piece of cheese so I'm gonna sit this one out.

 

as long as the cams line up with the valve cover (aluminum hub, not the plastic toothed end) then its in time.

 

Very helpful. Thanks mang.

 

im with 94awdcoupe, when it comes to cogged drives, pitch (space between teeth) is all that matters. if length mattered then after a couple revolutions, the longer or shorter belt would time differently. 1 crank revolution is say 10 teeth of belt movement, doesnt matter if the belt is 1' or 10' long, it stays the same.

 

Glad were all agreeing on this finally lol

 

Now hold on a moment. The Evo hole on the Fidanza gear is for the EVO 8-9 and may also be for Evo 1-4.

If you overlay the gears to a stock gear the dowel hole on the Evo hole will only line up on the EVO hole. On the DSM hole is is 1 tooth off 7.5*.

So now you have 2 things in the mix. A longer 64 belt plus a tooth off on the DSM gear hole that you should NOT be using. So at ZERO you start off at actual +7.5* and then you add the 64 belt which is throwing off the offset even more.

Its likely helped to put it back in the right direction with the longer belt.

If you put the cam dowel on the correct EVO pin, you will then see that you will need to advance or retard the gear the proper 3.75* to achieve ZERO.

You can also leave the DSM hole on the cams and retard your Fidanza gears to -7.5* and this will show you where you would be if using the correct EVO dowel hole.

Depending on the decking of the head its very well possible that being on the wrong dowel hole + using a longer belt has just about ZEROED your engine timing as they cancel each other out.

 

Anarchy correct me if I'm wrong but as stated a higher deck height yields the gears pulling to the right thus advanced .5 tooth w a 63 belt now, keeping the height constant( obviously) a 64 Puts you in a retarded position of halfa tooth which makes sense however if your head has been cut more or you block cut more that would bring either of these situations relatively closer to 0 at which point whether it's 2 * or 3.75* or whatever you would proceed to turn the gears to the point where the inner timing marks on the cam gear meet the ones on the vc which in theory is 3.75 * but accounting for other things such as amount of times decked how much was decked and how thick the hg is that theoretical value can vary within a few degrees yes?

 

K, keys think about this, how about vvt cars like Nissan and VW 1.8/2.7. They have a chain between the cams and an oil pressure driven tension lengthens out shortens the distance between the sprockets. The amount of chain links does not change between the sprockets only the distance. So do these cars not actually change can timing. Same concept.

The belt length, tooth spacing and ratio is unchanged between crank and cam pulleys sure, that obvious, but the distance the belt needs to travel changes.... I mean come on, is it not clear that this would "pull" the cams "forward", assuming the same number of teeth?

The only reason people end up retarding their cams with a 64 belt is because they end up with an extra tooth between crank and cam. The only reason for the different belt length is to keep the tensioner in the optimal range. But the change in deck height is half a tooth so that's how far, approximately, your cams end up being off one way or the other.

 

Oh Lord.

The last time my car wouldn't run after I did cams, it was a timing problem.

My cams were in the "EVO" hole. For my car to even idle with my gears in the EVO holes, my Ignition Timing MAP had to look like a roller coaster and still barely ran.

Low and behold, a million other members in another thread told me to put my dowel pins in the hole NOT labeled "EVO". I placed said cam dowels in said "other" holes, and whala, my car ran perfect, and I was able to set normal ignition timing, my car ran perfectly, pulled perfect vaccum, etc, when EVERYTHING in my tune had to be a mess for my car to run with dowels in the "EVO" holes.

Now we're in a different thread talking about timing, and when it seems fitting for the gears to fit in a different hole and that's why it lines up, my cam gears are in the wrong dowel pin again.

We tested the timing theory above not only on my motor, but on stanlsha's 2.4L, and his cam gears are only made for an Evo VIII-IX. Low and behold, his motor timed exactly as mine did, yielding the same exact results.

Maybe my cam gears are messed up, but I already dealt with this site telling me the opposite thing, which actually fixed my problem.

Basically, I timed it as I would a normal 4g63, and in the end it was off a degree or two on each cam gear, so I lined up said inner marks and we're good to go.

Everyone has had a different amount of material taken off their head and block deck, so there's no way a cam gear is automatically going to be 3.75 DEGREES off every single time. Advancing it in the beginning is the same as advancing it in the end, so we set them at 0, timed the car, and fixed the gap at the end with the cam gears, as every car is going to be different. A degree is a fraction of a mm, so saying that it's off 3.75* every single time just doesn't make sense.

 

Stanlsha, that is correct, for example a .5mm thicker hg will move you .625° advanced or so. This is why you always degree your cams, that and manufacturing incongruencies

 

degreeing your cams by actually measuring fixes this whole thing. So many variables, the values thrown around like 3.75 only takes into account one condition when obviously there is more that can affect it. you always degree cams by taking real measurements not just lining up the notches, that's part of the problem here and why everyone gets mixed results.

If you can grasp why machining or head gasket thickness matters, then three half tooth off concept should be easy to follow. If you had 12mm more deck height, you'd have one more tooth between crank and cam and you'd be dead on timing. well aside from machining, variables in cams and hg height.

 

Yeah its not cut and dry but even when I see others degree a motor its fairly close to the -3.75 range. Typically in the .75* range +/-.

If your car would not run well on the other dowel hole, you likely had cam timing off. Typically if you line up the crank to the T and then on the EVO dowel holes adjust the inner aluminum sliding cam line to point to the valve cover mark, then you're pretty much there.

 

akauf, I am amazed you are still mucking up the thread trying to convince people belt length changes timing .

maybe a picture will clear it up for you. the timing changes only when the length of yellow line changes. belt length has no affect on timing marks.

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The 3.75* thing is a base setting as would work on a 100% stock engine and head never being cut. Just as if you had a stock car with stock gears but had a hg done and ground the head. It would be off using stock gears but you have no adjustment. What I would do is line up your adjustable Cam gears to your stock gears and see which way they line up best and go from there. Then start with the base of 3.75* retarded and then work from there. I agree with 94AWD that the belt being for either 63 or 64 should only affect the tensioner side and not the savings between the cams themselves or the exhaust Cam to crank relationship on the fixed side of the belt,.

 

I would just put either belt on and degree the cams to their specs so it'll be perfectly in time.