The Ford Barn - View Single Post - The Terry Burtz 5 main bearing engine blocks are back on track.

Terry Burtz, Calif · 07-19-2019, 05:29 PM

This is not an update.

Thanks to all for your comments, questions, and encouragement.

I will try to answer a few questions.

Great to hear that the project is back on. Have you considered copying the original engine block with all of the defects, for the Purists in the club?
Regards, Ron

Yes, a goal is to make the purists happy. The cylinder block copied was manufactured after April, 1929 and has the 3 1/4 inch serial number pad and the small bump to add wall thickness when the hole from valve chamber to rear camshaft bearing was added. There were no exterior changes after the bump was added. Purists needing a cylinder block before April 1929 will have to remove the bump possibly shorten the serial number pad, and possibly remove material where the Throttle Control Assembly (A-9725) mounts. By using a CMM (Coordinate Measuring Machine) to create a SolidWorks model from the original cylinder block, all details that are not on the original Ford drawing (A-6015) such as draft, parting line locations, protrusions where water jacket support wires exited the cylinder block, and other details were captured. Steve Plucker has an extremely detailed Cylinder Block Guide that can be found at
http://www.plucks329s.org/pdf/engine...%20guide_1.pdf

Will this new technology address vibration?
Daren

Flathead answered your question by stating that a balance shaft is needed to fully eliminate vibration. A more detailed explanation can be found at http://www.modelaengine.com/13-crank...gn-a-6303.html
Second order vibration effects are another problem. Modern inline four cylinder engines incorporate two balance shafts with counterweights turning in opposite directions and at twice engine RPM. These balance shafts cancel a second order vibration caused because the two ascending pistons and two descending pistons do not always have identical opposing acceleration. Remember the connecting rod accelerations calculated earlier at TDC and BDC (+1936 g’s and –1081 g’s). Counterweights reduce crankshaft deflections and stress, but balance shafts do not. Balance shafts reduce loads on items external to the engine and increase passenger comfort. Since balance shafts do not reduce stresses in internal engine components and since there is no physical room for them in a Model A crankcase, they have not been considered in this engineering study.

07-19-2019, 05:29 PM	#33
Terry Burtz, Calif Senior Member Join Date: May 2010 Location: Campbell,CA, USA Posts: 318	Re: The Terry Burtz 5 main bearing engine blocks are back on track. This is not an update. Thanks to all for your comments, questions, and encouragement. I will try to answer a few questions. Great to hear that the project is back on. Have you considered copying the original engine block with all of the defects, for the Purists in the club? Regards, Ron Yes, a goal is to make the purists happy. The cylinder block copied was manufactured after April, 1929 and has the 3 1/4 inch serial number pad and the small bump to add wall thickness when the hole from valve chamber to rear camshaft bearing was added. There were no exterior changes after the bump was added. Purists needing a cylinder block before April 1929 will have to remove the bump possibly shorten the serial number pad, and possibly remove material where the Throttle Control Assembly (A-9725) mounts. By using a CMM (Coordinate Measuring Machine) to create a SolidWorks model from the original cylinder block, all details that are not on the original Ford drawing (A-6015) such as draft, parting line locations, protrusions where water jacket support wires exited the cylinder block, and other details were captured. Steve Plucker has an extremely detailed Cylinder Block Guide that can be found at http://www.plucks329s.org/pdf/engine...%20guide_1.pdf Will this new technology address vibration? Daren Flathead answered your question by stating that a balance shaft is needed to fully eliminate vibration. A more detailed explanation can be found at http://www.modelaengine.com/13-crank...gn-a-6303.html Second order vibration effects are another problem. Modern inline four cylinder engines incorporate two balance shafts with counterweights turning in opposite directions and at twice engine RPM. These balance shafts cancel a second order vibration caused because the two ascending pistons and two descending pistons do not always have identical opposing acceleration. Remember the connecting rod accelerations calculated earlier at TDC and BDC (+1936 g’s and –1081 g’s). Counterweights reduce crankshaft deflections and stress, but balance shafts do not. Balance shafts reduce loads on items external to the engine and increase passenger comfort. Since balance shafts do not reduce stresses in internal engine components and since there is no physical room for them in a Model A crankcase, they have not been considered in this engineering study.