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> Rocker set question?
NCRider
post Dec 21 2013, 05:17 PM
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Hi all I'm building my 2270 Raby kit. I might be over thinking this but looking at the way the swivel foot seats on the valve stem is off center. Im thinking this is so that the valve rotates and I should not try and line it up on the valve center line. I can do that if it is necessary. How much offset is to much? I ask because some valves are visually different as far as the off set goes. Also how much clearance should I have between the rocker stack and the end block?

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AndyB
post Dec 21 2013, 05:29 PM
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QUOTE(NCRider @ Dec 21 2013, 06:17 PM) *

Hi all I'm building my 2270 Raby kit. I might be over thinking this but looking at the way the swivel foot seats on the valve stem is off center. Im thinking this is so that the valve rotates and I should not try and line it up on the valve center line. I can do that if it is necessary. How much offset is to much? I ask because some valves are visually different as far as the off set goes. Also how much clearance should I have between the rocker stack and the end block?

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Doesn't the Raby kit come complete with everything you need? That's how its advertised or was or is the kit back? I know he is offering them still at the Club site. Or at least the advertisement says so. Just curious.
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Mark Henry
post Dec 21 2013, 05:43 PM
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QUOTE(NCRider @ Dec 21 2013, 06:17 PM) *

.....I might be over thinking this.....

Yep.
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NCRider
post Dec 21 2013, 08:49 PM
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Thanks Mark


".... Doesn't the Raby kit come complete ..."

Scarlet75 Yes it does .... but as stated many times ... you are the motor builder
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stugray
post Dec 22 2013, 10:43 AM
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The offset is ok.

When you are done I would be very interested in what you measure for Cam lift and Valve lift. Both intake & exhaust.
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r_towle
post Dec 22 2013, 03:54 PM
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The offset if fine and it's there to turn the valve each fit.

I am curious though,
Has anyone checked this setup out to make sure the valve is turning.
Who is to say that frictional force would not just turn the swivel foot instead of the valve?
Seems like it would be easier to turn that swivel foot, just base on mass, versus all the side friction that is on the valve stem at that moment.
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Mark Henry
post Dec 23 2013, 09:06 PM
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QUOTE(r_towle @ Dec 22 2013, 04:54 PM) *

The offset if fine and it's there to turn the valve each fit.

I am curious though,
Has anyone checked this setup out to make sure the valve is turning.
Who is to say that frictional force would not just turn the swivel foot instead of the valve?
Seems like it would be easier to turn that swivel foot, just base on mass, versus all the side friction that is on the valve stem at that moment.


Valve is going to turn no matter what. I grind the keepers so they shouldn't be able to turn, they still do. They at least twist enough that it has never been an issue.
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messix
post Dec 23 2013, 11:07 PM
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I read some where that the valve spring is what induces the valve to rotate

http://courses.washington.edu/engr100/Sect...lve%20Train.htm
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Mark Henry
post Dec 24 2013, 08:42 AM
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QUOTE(messix @ Dec 24 2013, 12:07 AM) *

I read some where that the valve spring is what induces the valve to rotate

http://courses.washington.edu/engr100/Sect...lve%20Train.htm


Either an educator or engineer wrote that. (IMG:style_emoticons/default/rolleyes.gif)
Easier way of explaining this is "as the valve spring wraps and unwraps it induces valve rotation".
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Jake Raby
post Dec 24 2013, 08:52 AM
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.004 lateral clearance is perfect for the rocker assembly, some adjustment may be necessary to the aluminum spacer to allow for this.

The contact point of the swivel foot adjuster to the valve stem isn't critical, as long as the entire stem of the valve is covered by the adjuster, there are no issues. The picture that was posted is OK, but barely.

I sold my Type 4 Store to LN Engineering, Charles plans on bringing the kits back ASAP. I discontinued them 3 years ago and life has been much better since I did. With the store gone and my only focus on developing products and building engines, it will be even better!
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NCRider
post Dec 24 2013, 04:58 PM
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Thanks Jake

I have been playing around with getting the foot centered on the stem and yes I have had to remove material from the spacer & block to get both rockers centered on the stem. You will need a few extra shims. I was able to source some stainless steel Rockwell C25 from MSC. Had to flap the ID to get the shaft clearance right.

Mark

The spring rotating the valve makes more since than a off center foot on the stem.

Jeff

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gothspeed
post Dec 24 2013, 11:57 PM
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QUOTE(messix @ Dec 23 2013, 09:07 PM) *

I read some where that the valve spring is what induces the valve to rotate

http://courses.washington.edu/engr100/Sect...lve%20Train.htm

+1 ........ the entire valve, spring, retainer and keepers would rotate together .... (IMG:style_emoticons/default/smile.gif)

But the valves will indeed rotate a little, with or without swivel adjusters.
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euro911
post Dec 25 2013, 12:19 AM
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If that's your engine, don't forget the lock nuts (IMG:style_emoticons/default/sad.gif)
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Jake Raby
post Dec 25 2013, 06:46 AM
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I prefer the swivel foot a little off center.. Thats just me.
It worked for 160K in my personal engine just fine.
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stugray
post Dec 25 2013, 01:30 PM
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I would really like to hear what the valve vs cam lift measurements are.
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914_teener
post Dec 26 2013, 06:15 PM
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QUOTE(gothspeed @ Dec 24 2013, 09:57 PM) *

QUOTE(messix @ Dec 23 2013, 09:07 PM) *

I read some where that the valve spring is what induces the valve to rotate

http://courses.washington.edu/engr100/Sect...lve%20Train.htm

+1 ........ the entire valve, spring, retainer and keepers would rotate together .... (IMG:style_emoticons/default/smile.gif)

But the valves will indeed rotate a little, with or without swivel adjusters.



+2

Are the shims "spring" type or just flat shims?
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NCRider
post Dec 27 2013, 08:53 AM
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They are flat stainless steel shims that come in the solid spacer kit.
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