Engine: More Hot Rod engine parts...

[Mike Van Veghten]

The cam grinder that's doing the roller cams for us is also going to make adjustable upper timing gears.

Again please go the the Stude Racing site to the thread below -

http://racingstudebakers.com/foo/viewtopic.php?f=1&t=2405

This gear will be affordable and work under the stock timing gear cover. If you want to get your camshaft of ANY brand to the closer location it was designed to be in, think about one of these.

Not sure of the exact cost yet (hopefully this weekend) but it won't be too much more than the aftermarket aluminum gears currently available.

Mike

[Kdancy]

Mike,
Please elaborate on this-- good for knowledge base--
"Now this won't help blocks that have been line bored by a shop that doesn't understand how a double gear system works and shortened the cam to crank dimension."

[BobPalma]

Kdancy: The problem is this: If you line-bore a block, you remove just a little metal from the top of the main bearing cavities in the block itself. This moves the cranksahft microscopically up in the block just a little.

This changes the dimension from the centerline of the crank to the centerline of the camshaft, putting the timing gears just a little closer to each other. Obviously, they will then mesh differently than when the crankshaft was just a little further away from the camshaft. BP

[R2Andrea]

This gear will be affordable and work under the stock timing gear cover. If you want to get your camshaft of ANY brand to the closer location it was designed to be in, think about one of these.


I think he's refering to location in terms of timing, rather than physical location in the block (cam centerline vs crank centerline).

[Mike Van Veghten]

While Bob is correct....it's MUCH more than "microscopically", unless the microscope's power is turned WAY down..!
A coupla thousandths can make or break the gear mesh, espicially when used with the oversized aluminum gear that I believe is still out there that's too large as it coumes out of the box.
But yea..."normally", it should be about the same as a thin piece of writing paper.

And R2Andy is also correct, I'm refering to the rotational relationship between the cam and the crankshaft. Most cams are ground a little advanced or retarded, few are ground at the "zero" point. I"ve "heard" (from some reliable sources) that the Stude cams are a coupla degrees retarded.
For those that just drive around town and don't take too many high speed runs across country, advancing the cam 2 or 3 degrees can have a great positive effect on power and milage.

Depending on the way the cam is ground, advancing the cam will cause everything in the combustion chamber to happen a little earlier in the cycle and provide more usable power. This advancing of the cam, will cause the pressure, or dynamic compression to go up, thus raising the power curve at low to moderate speeds. And in the case of the Stude engine, will go all the way to freeway speeds (65/75mph).

Mike

[JoeHall]

Has anyone experienced a line bore that resulted in the cam & crank gears being too close? I dropped a 289 block of a couple of days ago. The guys there seemed very competent, but GM Performance is their specialty. I think I'd better mention the 289 has timing gears instead of a chain.

[Mike Van Veghten]

Joe -

On one hand, just because they do mostly Chevy stuff...doesn't mean they can't do a good job on the Stude engine too.
Think about it...how many Stude engines are there being rebuilt..!

On the other hand, if they've never done a Stude engine....YES...they need to know the coupla qurks that the Stude has...like having the timing gears and no chain. Remember where the crank thrust shims go..."you" need to remember to reinstall the pipe plug in the distributer cavity in the block, maybe the proper installation method of the wrist pin pinch bolts in the rods. Some of those things.

Otherwise, it's just an engine, it requires the same things to make it work as other engines.

Mike