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It is my understanding that Dodge started retarding the cam timing at the timing chain for emissions. When did they start this and how did they do this (different timing chain? different crank?)
And how would your engine run if these engines had the cam timing changed to straight up?
 

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any stock timing chain and gears that you buy right now will be retarded/ only the good double rollers with the three keyways aint and then they give you the choice / advanced-straight up-retarded depending on yer cam center line / a retarded motor run straight up would have more low end
 

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DODGEBOYS said:
any stock timing chain and gears that you buy right now will be retarded/ only the good double rollers with the three keyways aint and then they give you the choice / advanced-straight up-retarded depending on yer cam center line / a retarded motor run straight up would have more low end
ok so what about a double roller set that doesnt have the 3 key ways? will this set have it retarded as well? if so that might explain part of my problem

eric
 

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I'm not sure about all this. It was my understanding that the retard was done in the cam. Its best to just degree your cam and adjust as needed. I will say every engine i've degreed was either straight up or needed to be advanced. I only use double rollar chains that have 3 keyways. I don't know about all timing chain manufacturers but one 3 keyway chain I used moved the cam 4 degrees advance or retard. Since the crank turns at twice the speed of the cam that is 8 degrees at the crank. When your degreeing a cam your going by crank degrees. So that particular chain moved the cam 8 degrees either way which was too much. The same goes for offset cam keys. Double the degrees of offset the key is machined for and thats how many degrees it will change at the crank.
 

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chrysler300le said:
I'm not sure about all this. It was my understanding that the retard was done in the cam. Its best to just degree your cam and adjust as needed. I will say every engine i've degreed was either straight up or needed to be advanced. I only use double rollar chains that have 3 keyways. I don't know about all timing chain manufacturers but one 3 keyway chain I used moved the cam 4 degrees advance or retard. Since the crank turns at twice the speed of the cam that is 8 degrees at the crank. When your degreeing a cam your going by crank degrees. So that particular chain moved the cam 8 degrees either way which was too much. The same goes for offset cam keys. Double the degrees of offset the key is machined for and thats how many degrees it will change at the crank.
yeah doug, i had already planned on degreeing the cam, i plan on ordering the degree kit and cam keys here in the next week or so.

still had me a bit puzzled about the chain being designed to retard the cam.

the reason i asked about the double roller without keyways is because that is the kind mine is.

eric
 

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If you are degree'ing a cam does the 3 key placements as opposed to just 1 on a regular crank sprocket matter? Since you are adjusting the cam degree anyway, I believe matching it to where you want it in relation to tdc on #1 (guessing thats whats done). If so, then why would the 3 key crank sprocket matter? Also, can somebody medium simply explain the advantages in degreeing the cam. I can see that idle could be optimized to run better, but isnt it pretty much a linear transition beyond that point in revs? Just a different starting point sort of thing?
 

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Bummo said:
If you are degree'ing a cam does the 3 key placements as opposed to just 1 on a regular crank sprocket matter? Since you are adjusting the cam degree anyway, I believe matching it to where you want it in relation to tdc on #1 (guessing thats whats done). If so, then why would the 3 key crank sprocket matter? Also, can somebody medium simply explain the advantages in degreeing the cam. I can see that idle could be optimized to run better, but isnt it pretty much a linear transition beyond that point in revs? Just a different starting point sort of thing?
technically you are right, since i am going to be degreeing it anyway then the 3 keyways really dont matter, except it would have saved me from buying the cam keys.

as far as the advantages in degreeing, say for instance that some dumbass on the machining line decided not to pay attention one day and they ground in the wrong centerline on the cam, or say they put the wrong cam in the box and it doesnt match the cam card you have. without degreeing the cam you will never know this and will be wondering exactly what is wrong with your engine and why it isnt running the way your cam card says it should

also, it isnt just idle that is affected buy degreeing, more or less what you are doing when degreeing is changing the installed centerline on the cam and effectively changing the RPM range that the cam works in.

for instance the cam i am using is a 1500-4500 RPM cam and it has a 112 centerline, by advancing the cam i am more or less telling the cam it has say a 110 or a 108 centerline, thereby effectively moving my RPM range down to around 1000-3500 RPM

eric
 

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Just lining up the dots isn't good enough. Things such as crank indexing. block core shift. manufacturing tolerences of the timing chain and cam all can affect the cam timing. They can all add up and make the cam several degrees off. A cam that is 4 degrees retarded will make the cam's power come in about 1500-2000 rpm later. This kills all low end power.
 

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chrysler300le said:
Just lining up the dots isn't good enough. Things such as crank indexing. block core shift. manufacturing tolerences of the timing chain and cam all can affect the cam timing. They can all add up and make the cam several degrees off. A cam that is 4 degrees retarded will make the cam's power come in about 1500-2000 rpm later. This kills all low end power.
yeah just ask me about this, i am sure that is what i am gonna find when i degree my cam. :(

eric
 

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I just advanced the cam on my 94 Ram 4 degrees. I degreed the cam when i re-ringed it and found that it was 2-4 degrees retarded. I ran it that way, but it was down on power and fuel mileage. Kicked out of OD alot. I finally installed the keys and the power surge i use to get at 45 mph in 1st gear WOT now is at 15 mph(no tach). Now if i just had a looser converter i would have power as soon as i stomped on the gas.
 

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chrysler300le said:
I just advanced the cam on my 94 Ram 4 degrees. I degreed the cam when i re-ringed it and found that it was 2-4 degrees retarded. I ran it that way, but it was down on power and fuel mileage. Kicked out of OD alot. I finally installed the keys and the power surge i use to get at 45 mph in 1st gear WOT now is at 15 mph(no tach). Now if i just had a looser converter i would have power as soon as i stomped on the gas.
hmmm this is all sounding fmailiar. lol

eric
 
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