Valve spring install height

johnmead

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What is the installed height of the valve springs on a post war Vincent? I could not find any reference to it in any of the references I have, but may have missed it.

John
 

stumpy lord

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hi ,
Paul Richardsons book the Vincent page 49.

outer spring 2.1/4 inches, inner2.7/32 inches.
stumpy lord.
What is the installed height of the valve springs on a post war Vincent? I could not find any reference to it in any of the references I have, but may have missed it.

John
 

chankly bore

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Dimensions quoted are free lengths, not installed height. You haven't got much room to muck abart wiv installed height because of the way the jigger is designed!
 

A-BCD

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You might get something by scaling this drawing - looks like the installed height of the outer spring is 1 .25"
inletvalvegear.jpg
 

johnmead

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Thank you for the drawing. The reason I am asking is that I am going to install beehive springs. They are smaller in diameter, made from oval cross section wire and are wrapped in a beehive shape to allow for more lift without binding.

Since they are smaller in diameter I made new ET40s with a flat bottom where the base of the spring sits and a narrower post because I am using valve spring seats and shims to get the correct installed height.

I am also going to have the valve stems machined to use modern keepers and titanium retainers. The cams I am using make max hp at 6800rpm and I don't trust the ET38 keepers.

John
 

john998

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Hello,
Wise to be wary of alloy ET37 valve spring cap, had one fail 40 years ago. All that saved a disaster was the rocker pad being tight on the valve stem.
Had the head off before the engine was cold, no damage other than the ET37.
This was in the era of poor quality spares, it was perhaps made of the wrong material.
The Vincent valve gear is amazingly robust, have seen 9000 revs twice, not by intension but by accident.

Regards John.
 

johnmead

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The ET37s I will be using are titanium, as are the keepers. Once I get the installed height of the valve springs I will be able to cut the sloot for the internal rib on the keeper.

John
 

Monkeypants

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"I am also going to have the valve stems machined to use modern keepers and titanium retainers. The cams I am using make max hp at 6800rpm and I don't trust the ET38 keepers."

John

John, what cams are you using?

Glen
 

davidd

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I use R-D valvle springs, keepers and buckets. The buckets are titanium. Steve Hamel installed the beehive springs on his heads three or four years ago. I install the springs and vlaves with the shims to adjust the pressure. I then go through a selection of caps to make sure I have some clearance. I have only once had to modify a cap for clearance. I have some alloy washers that I use in place of the gasket that are a little higher than the gasket if necessary. 0.500" lift intake.

If you run into a problem and you need a little extra height, Terry Prince makes higher caps that have an 'O' ring gasket. No logo.

David
 
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