Subject: Re: [Spridgets] Valve Guide Position

From: "Dean Hedin" <[email-masked]>
Date: Tue, 20 Nov 2012 18:54:59 -0500

I'm putting together a 1098 12G295 head this winter.

I thought I would machine a drift and a spacer to assist when I install the
new valve guides.  My spacer is a cylindrical piece of steel that fits in
the spring pocket that I can use to tap the guide down to the gauged height.

The manual indicated that 1098 guides were set .540" above the head.
The existing guides in my head are set to .470" above the head.
Actually the ones in the head have some variation +- .010.

I'm guessing the previous owner of the head either didn't know what they
were doing or they were running a radical cam.

Is there some other reason why they are set this low?  Like different valve
guide seals?

Speaking of seals, who offers Viton valve guide seals for the spridget
engine?  Are they worth it?

I was going to go with the silicone bronze guides unless someone can tell me
otherwise.

Thanks in advance for any suggestions.  
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[email-masked]

Archive: http://www.team.net/archive

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From: [email-masked]
Date: Thu, 22 Nov 2012 13:21:34 -0500 (EST)

Are you sure they are not Ti?
 
In a message dated 22/11/2012 01:41:37 Coordinated Universal Time,  
[email-masked] writes:

The  spring holders are anodized green aluminum.
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[email-masked]

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From: "Dean Hedin" <[email-masked]>
Date: Thu, 22 Nov 2012 22:43:26 -0500

Good question.

The green anodizing makes it hard to determine.

I have a watch that has a titanium case, and I know what the bare metal
looks and feels like.

The lightness of the retainer in my hand makes me think that it is aluminum.
But it is difficult to be certain.

I'll have to calculate the volume and then weigh it carefully to be sure.

Is there a known aftermarket outfit that is making these in titanium and
anodizing them green?

There are no manufacturer's markings on these.

I'm thinking that the previous owner of this head might have had rocker arms
with an aggressive ratio. 

This may be the reason why the guides were set lower to the head.

I better get this head checked for cracks.  I don't see any visible issues,
but if it's been raced

then it might have some hidden flaw that I can't see with my eyes. 

  _____  

From: [email-masked] [mailto:[email-masked]] 
Sent: Thursday, November 22, 2012 1:22 PM
To: [email-masked]
Cc: [email-masked]
Subject: Re: [Spridgets] Valve Guide Position

[email-masked]

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From: [email-masked]
Date: Fri, 23 Nov 2012 04:08:57 -0500 (EST)

Kent Cams used to retail them (in green) and probably still do.  Some  of
their stuff is made by Titan (like the roller rockers they sell).  David
Anton at APT might know.

In an old Kent Cams catalogue they do list aluminium as well as Ti
retainers for the A-series (photo is b&w).

I can't imagine anyone would be using lightweight retainers on a standard
cam and rockers unless the rules forced them to so 1.5 ratio is my guess.

Regards

Weslake-Monza

In a message dated 23/11/2012 03:43:27 Coordinated Universal Time,
[email-masked] writes:

Good  question.
The green anodizing  makes it hard to determine.
I have a watch that  has a titanium case, and I know what the bare metal
looks and feels  like.
The lightness of the  retainer in my hand makes me think that it is
aluminum.  But it is  difficult to be certain.
Ibll have to  calculate the volume and then weigh it carefully to be  sure.
Is there a known  aftermarket outfit that is making these in titanium and
anodizing them  green?
There are no  manufacturerbs markings on these.
Ibm thinking that the  previous owner of this head might have had rocker
arms with an aggressive  ratio.
This may be the  reason why the guides were set lower to the head.
I better get this  head checked for cracks.  I donbt see any visible
issues, but if itbs  been raced
then it might have  some hidden flaw that I canbt see with my eyes.

____________________________________

[email-masked]