Lets say you moved the crank key 2 degrees.....Would that have the same effect as adjusting a cam gear 2 degrees? Or is there a formula that I am missing here?

Thanks!

 

you have to rotate the crank 2 rotations for 1 rotation of the cams.

 

Exactly what I was looking for....

So 2 degrees of the crank is 1 degree of the cam. Is the the exact conversion? Can you explain "why" that conversion applies?

Thanks for the information.

 

It's a 4 stroke motor, so the piston has to go up and down 4 times for one cycle. The cams must rotate at half that speed to work, so the gear on the crank has half the number of teeth as the cam gears.

 

So the ratio is exactly 2:1...correct?

When the crank is "keyed" do they weld the key channel and then machine a new channel? Or is the existing channel filed or made "wider" by some other means?

Thanks!

 

Oh yes there is a gear, what do you think the timing belt is turned by?

 

yeah...I edited that when I went out to the garage....

I counted 38 teeth on the cam and 19 on the crank gear....

2:1 sounds right to me!




Modified by jisu009 at 11:22 PM 12/12/2004

 

I figured it was just a little brain fart.

Yeah, it's 2:1. For it to be 1:1, the lobes on the cam would have to take up 1/4 of the circumference of the cam, instead of the 1/2 they do now. That is obvioustly a terrible design, which is why cams are made like they are for like 100 years.

And I hope you counted 34 on the cam gears and 18 on the crank gear...

 

38 on the cam

19 on the crank

 

Wierd, I just counted the one off my B16, and it's got 18. But 38:19 is 2:1, so I dunno. I don't feel like digging my cam gears out from under the rest of the head to count, but I believe you.

 

I suppose you don't actully modify the crank, but instead you modify or have a new gear made for the crank?

Anyone know where to have this piece made....or has anyone ever done this?

Yes I know there is an easier way...but I have my reasons.


Modified by jisu009 at 11:39 AM 12/13/2004