[Fot] "Vernier" Adjustable Cam Sprocket

[Scott Janzen]

I use what Richard Good sells - don’t know if he has an equivalent for the Tr4.  Never had anything loosen up.  the heads of the bolts that attach it to the cam are drilled and wired.

On Sep 23, 2024, at 8:35 AM, Erik Jacobsen via Fot <fot at autox.team.net> wrote:

Phil,
My two cents (no cash value ). I have used vernier sprockets on my TR3, my wife's TR6 and my Bugeye race cars, and haven't had any issues. I don't torque them to a specific number since mine are all aluminum, but I do Loctite blue the screws. Have never had any slipping or wear issues. And the ability to get the cam timing just right is awfully nice, especially on the 3 as it's so critical. 

Cheers,
Jake

On Monday, September 23, 2024 at 07:21:34 AM CDT, vfracing--- via Fot <fot at autox.team.net> wrote:


Hi all;

After completely and embarassingly blowing cam timing on two consecutive engines i bought from Moss a so-called "vernier" adjustable cam timing sprocket made by Powertune.  It consists of a hub and sprocket held in relative position to each other with 6 Allen head cap screws near the periphery of the sprocket.  The cap screws have a fancy machined and anodized aluminum washer under them to spread the load. (See picture).

My question/concerns are:

Is this robust enough to hold position?  Is the friction between hub and sprocket sufficient?  

Do the aluminum "washers" hold up or do they creep over time, reducing the clamping load and allowing it to slip?

Does anyone have a suggestion for the torque spec on the 6 Allen headed cap screws (no specs given with the sprocket) or the hub to cam (book says 24 - 26 ft lbs).

Should I assemble this Loctite between the hub and sprocket to keep it from slipping?

Or should I send this back and get a more robust unit?  If so, where can I get a better one?

Thanks!


Phil Gott


_______________________________________________
fot at autox.team.net <mailto:fot at autox.team.net>

http://www.fot-racing.com <http://www.fot-racing.com/>

Donate: http://www.team.net/donate.html <http://www.team.net/donate.html>
Archive: http://autox.team.net/archive <http://autox.team.net/archive> http://www.team.net/pipermail/fot <http://www.team.net/pipermail/fot>
Unsubscribe/Manage: http://autox.team.net/mailman/options/fot/kekjacobsen@yahoo.com <http://autox.team.net/mailman/options/fot/kekjacobsen@yahoo.com>


_______________________________________________
fot at autox.team.net

http://www.fot-racing.com

Donate: http://www.team.net/donate.html
Archive: http://autox.team.net/archive http://www.team.net/pipermail/fot
Unsubscribe/Manage: http://autox.team.net/mailman/options/fot/sjanzen@me.com



-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://autox.team.net/pipermail/fot/attachments/20240923/f12434b2/attachment.htm>