There is/was a problem with the dimensioning in the drawing. I brought this to Jerry's attention in an email. He corrected it in later drawing sets and sent me an update. Jerry scanned the new drawing and sent a PDF to me.

I have drawing set #66.

Somewhere there is a web link detailing all the revisions. Maybe Allen can make that known to you.

Allen should probably send you new copies of the sheets that have changed since your copy version.

Here is a copy of the email message he sent me. There were a couple of other issues I mentioned as well.

This may be confusing. There are my comments followed by his response (s).

I hope this clarifies the problem for you.

Dave Sage

A couple of issues with the V4 drawings – errors - maybe not - but anomalies none the less:

On sheet #6 the dimension of .307 should be .305 otherwise adding up all the given dimensions across the block comes out to more than the overall dimension shown of 3.285. I’m not sure how this could happen on a CAD drawing. (rounding errors ?)

You are correct, it should be .305".

On sheet #6 the width of the head deck (top of the block) can be calculated as 3.285 minus .077 giving 3.208. On sheet 7 the same thing can be calculated as 2.990 + .175 + .032 giving 3.197 a fair difference (11 thou). Not a biggy but still perplexing given it’s CAD.

The .175" dimension should be .186" instead, but if the other dimensions are adhered to it is moot. Granted

the dimension needs to be correct anyway, or else just not included. I use the CAD for design as well as

for output of the drawings. Some of these dimension errors are remnants of multiple design changes where

some affected item dimension corrections were missed. Also contributing is 69 year old gray matter! All

the above will be corrected for all future plan sets along with a couple on Sheet #16 as well. The 3.210" to

3.208" and 3.080" to 3.078" due to assumed .002" added to the .128" for cleaning up the mill

marks from Step #3 thus the .130" dimension. See below.......

If you look at the pictures of the finished engine, the heads seems to overhang the block an obvious amount all around which looks good. But given the dimensions above and looking at sheet 22 and 20 there will be no overhang on the ends and only 60thou on the top and bottom. The head is drawn as 3.200 long (only 8hou or so different than the 3.208 or 3.197 above)?

You missed the .128" of material milled away (plus .002" for cleaning up the mill marks) all around the gear

case cover on the flywheel end of the block in Step #3 on Sheet #16. This brings the length of the cylinder banks

to 3.078". With the heads at 3.200" long, there is .061" of head overhang on each cylinder bank end.

Thank you for pointing out the dimension errors. I always want to know about them so I can correct them.

Regards,

Jerry E. Howel