C2 SHP timing cover

[Steve D.]

I am building my small journal crank 327 as an SHP engine using the 8" balancer (PN 3817173). I have not located a part number on the existing timing cover, but I measured (estimated with a protractor) the position of the timing mark to be approximately 40 degrees ( between 1 and 2 o'clock). Does this sound like the correct position for this balancer?

Steve

[Duke W.]

Re: C2 SHP timing cover

It's actually about 43 degrees from vertical. You need the SHP front cover that has the timing tab located at a greater radial distance to clear the 8" balancer.

The "A" mark (ten degrees advance) is actually the point where the tab plane is tangent to the arc centered on the crankshaft axis, so there is no parallax when you read 10. The tab becomes less accurate as you read timing values farther from "A". If you align the balancer to the "A" mark the angle should be 38 degrees.

Duke

[Tracy C.]

Re: C2 SHP timing cover

Steve,

There is no part number on the timing cover, but it should have a timing tab that looks like this. The distance from the bottom side of the tab to the centerline of the crank is 4 3/32". I didn't attempt to measure the angle, but I suspect Duke has an engineering drawing that provides backup for his 43degree info.

If you need anything else, I'd be glad to help.

tc

[Michael H.]

Re: C2 SHP timing cover

Steve,

Tracy has it right. If the distance from the crankshaft to the timing tab is slightly more than 4", then the cover is correct for an 8" balancer. Finding out if you have a pre 69 or post 69 cover isn't real difficult. In 69, the timing tab on the cover was moved up 10 degrees, along with the mark on the balancer so you need a 68 and earlier cover to match the 68 and earlier 3817173 dampner that you have. The zero line should be at roughly 45 degrees when number one piston is at TDC and as long as you have the opportunity, this is a good time to establish a true TDC as the balancers and cover tabs tend to be a little inaccurate.

Using the "A" mark may be SLIGHTLY more accurate but we're only talkng about a tenth of a degree here. Besides, I think the math is wrong. Aligning the mark on the balancer with the "A" would be a difference of 10 degrees for a total of 35 degrees, or 33 degrees if you use the 43 degree location for the mark.

Michael

[Steve D.]

Re: C2 SHP timing cover

I measured the distance from the bottom of the tab to the center of the crank hole and got just a tad over 4", so I guess I'm ok.

Thanks everyone.

Steve