View Full Version : crank woodruff key location?


Brian Callahan
08-19-2012, 09:46:41 PM
Anyone know the nominal angular position of the torsional damper woodruff key versus the block when the #1 piston is at TDC? Engine is a Mark IV big block, if that makes a difference.

We're building a trigger wheel and want to get it right but measuring the existing parts is difficult.

77nomad
08-20-2012, 12:34:19 AM
You can buy a stamped steel wheel for about 30 bucks. Unless you got a laser cnc then rock on. This is the one I was talking about.

http://www.diyautotune.com/catalog/images/products/tw36-1_825_med.jpg

Damon
08-20-2012, 08:23:42 AM
45*. Exactly.

It's perfectly in line with the #1 crank throw. So when Piston #1 is at TDC the keyway is pointing directly at the middle of the #1 piston bore.

True for small blocks as well.

Brian Callahan
08-20-2012, 03:38:19 PM
Thanks, Damon.

Nomad, yeah that would have been the preferred solution and in fact is what we have been using to date. But, we changed some stuff including the power steering pump location and also switched to a belt-type cam drive. All of that forced us to put the crank sensor in an axial position that would not allow a regular wheel. So, Kevin is making a top-hat shaped wheel.

Brian Callahan
08-20-2012, 03:49:26 PM
A cartoon of the new trigger wheel (left) and our old one (right). The new one is shown without teeth. Because of its axial thickness, we can't use an off-the-shelf disk-style wheel.
http://i233.photobucket.com/albums/ee165/br1ian/cranktriggerwheelcartoon-1.png

Brian Callahan
12-10-2012, 03:22:07 AM
Here is the finished piece.
http://brian-callahan.com/Brians stuff/Camaro-pix/engine/trigger wheel front view.jpg
http://brian-callahan.com/Brians stuff/Camaro-pix/engine/trigger wheel iso view.jpg