The Ford Barn - View Single Post - How to do an engine assessment on my wifes 81A?

41ford1 · 08-05-2015, 09:33 PM

I don't know if the C7RA-A head is equal to the 77 head listed in service bulletin 6000. If it is, that CR is 7.5:1. The 81T head has a CR of 6.2:1. My info comes from SB 6000 dated Feb. 6 1942. Both heads are for domed pistons.
If this engine runs well and has no strange noises run it as is. No need to fix something that ain't broke.

08-05-2015, 09:33 PM	#11
41ford1 Senior Member Join Date: May 2010 Location: ManchVegas, New Hampshah Posts: 1,591	Re: How to do an engine assessment on my wifes 81A? I don't know if the C7RA-A head is equal to the 77 head listed in service bulletin 6000. If it is, that CR is 7.5:1. The 81T head has a CR of 6.2:1. My info comes from SB 6000 dated Feb. 6 1942. Both heads are for domed pistons. If this engine runs well and has no strange noises run it as is. No need to fix something that ain't broke. __________________ You are never to old to enjoy your childhood. Forty1fordpickup on the HAMB.