Is your maximum lift at 108 degrees atdc [assuming no built in retard?].
Figures you give indicae 300 degree of opening. half of that is 150.
15042 = 108 which is where max lift should be.
On Fri, Oct 4, 2013 at 12:05 PM, Joe Guinan <joeg@neb.rr.com> wrote:
> Friends,
>
> I've finally installed the used Kastner A7 cam in my 1147 race engine and
> am
> having trouble getting it timed correctly. When I set the #2 valve (intake
> on #1 Cylinder) to open at 42 degrees, I cannot get the closing number
> anywhere close. It's at 60 something on closing. Haven't even checked where
> the #1 valve starts to open, as this seems so wrong.
>
> Specs I received from FOT Aaron Johnson are below.
> - Inlet opens 42 Inlet Closes 76
> - Exhaust opens 76 Exhaust close 42
> - Duration 293 Lift at valve .410
> - Checking clearance at the camshaft is .013
> - Rocker arm clearance is .020
>
> Information I received from Kas himself is close to the above;
> "That cam was done early on but it will work fine. The timing is Inlet
> 42-71
> and the exhaust is 71-42. The cam has 293 degree duration and .410 lift at
> the valve. As I remember the checking clearance is .013" and the running
> clearance is .020"."
>
> Kas also added, "Just for your information I believe that cam is done on a
> factory billet meaning that the base circle is very close to the stock
> diameter. Check to see if it is. If so, you can get a dynamite cam
> profile
> put on that cam at Moon Equipment. You cannot E-mail them but phone and ask
> for Bill Jenks and then tell him you want the A-10-A. This will go onto
> that
> cam fine if it is the factory billet I used for lots of the camshafts. That
> was the latest grind (54 - 90 and the gross lift is .517" )and it was
> terrific but you do need high compression to deal with it."
>
> Note the difference in closing measurements in the two sets of specs?
>
> I know I have TDC on the crank set correctly. I'm seeing 42 degrees on the
> degree wheel when the dial indicator on the top of the pushrod shows the
> valve has opened .013 inch. The valve stays open like it should for most of
> a rotation but is only at 60 something on the degree wheel when it has
> closed to only being open .013 inch.
>
> What am I missing / not understanding?
>
> I already have the head installed, but I'm about ready to pull the cam out
> and get a new one, or follow Kas's suggestion to send it out for a regrind.
> I am running high compression with "pop-up" pistons. Something about this
> cam just doesn't seem right, and adds to my suspicions about running a used
> cam in this newly rebuilt engine. Hate to spend the money and time, but if
> I
> have to do it, I might as well do it now.
>
> Thoughts and opinions welcome...
>
>
> Thanks,
>
> "Jedi"
> Joe Guinan
> Fremont, NE
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>
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