The Ford Barn

DavidG · 11-21-2013, 01:31 PM

I'd appreciate experience-based opinions on the maximum safe overbore on a '33-'34 V-8 block; specifically regarding the wisdom or lack thereof of going to +.060 versus sleeving back to standard.

David J · 11-21-2013, 01:49 PM

I have two that are .060 in cars and it doesn't seem to bother anything .

Quote:

Originally Posted by DavidG

I'd appreciate experience-based opinions on the maximum safe overbore on a '33-'34 V-8 block; specifically regarding the wisdom or lack thereof of going to +.060 versus sleeving back to standard.

deuce_roadster · 11-21-2013, 05:12 PM

Every block is different on the inside due to minor core position changes. I don't think you can make a blanket statement about this. You have to sonic test the block to see how much material is left. Keep in mind, the inside has rusted and there will be spots where it is thinner then others. My engine machinist sonic tests each cylinder in 4 places top and bottom before determining how much bore any block will take. He leaves a minimum of .100 thickness when finished.
This person is an FAA inspector of homebuilts, A&P and builds aircraft engines also so I trust his judgment. I suspect Rotorwrench has similar qualifications.

Mart · 11-21-2013, 07:20 PM

I think a friend of mine has an early motor that is bored +.080. So +.060 should be ok, but (as stated) as rust and time takes it's toll, maybe a sonic test should be carried out first.

Mart

Charlie ny · 11-21-2013, 08:18 PM

Sponsored Links (Register now to hide all advertisements)

What d r says
Each block is different and core shift in early blocks is ugly. I had a 'decent'
'36 LB block and the rebuilder shot blasted the water jackets and blew a hole in two
bores on the right bank from the water jacket into the bore. On the same bank
the side wall blew thru from the inside out. We sonic everything now....CHEAP
insurance.
Charlie ny

11-21-2013, 01:31 PM	#1
DavidG Senior Member Join Date: May 2010 Location: southeastern Michigan Posts: 10,101	Maximum safe bore on a '33-'34 block I'd appreciate experience-based opinions on the maximum safe overbore on a '33-'34 V-8 block; specifically regarding the wisdom or lack thereof of going to +.060 versus sleeving back to standard.

11-21-2013, 05:12 PM	#3
deuce_roadster Senior Member Join Date: Oct 2011 Location: Shelton, WA Posts: 3,800	Re: Maximum safe bore on a '33-'34 block Every block is different on the inside due to minor core position changes. I don't think you can make a blanket statement about this. You have to sonic test the block to see how much material is left. Keep in mind, the inside has rusted and there will be spots where it is thinner then others. My engine machinist sonic tests each cylinder in 4 places top and bottom before determining how much bore any block will take. He leaves a minimum of .100 thickness when finished. This person is an FAA inspector of homebuilts, A&P and builds aircraft engines also so I trust his judgment. I suspect Rotorwrench has similar qualifications.

11-21-2013, 07:20 PM	#4
Mart Senior Member Join Date: May 2010 Location: Solihull, England. Posts: 8,747	Re: Maximum safe bore on a '33-'34 block I think a friend of mine has an early motor that is bored +.080. So +.060 should be ok, but (as stated) as rust and time takes it's toll, maybe a sonic test should be carried out first. Mart

11-21-2013, 08:18 PM	#5
Charlie ny BANNED Join Date: May 2010 Posts: 3,019	Re: Maximum safe bore on a '33-'34 block Sponsored Links (Register now to hide all advertisements) What d r says Each block is different and core shift in early blocks is ugly. I had a 'decent' '36 LB block and the rebuilder shot blasted the water jackets and blew a hole in two bores on the right bank from the water jacket into the bore. On the same bank the side wall blew thru from the inside out. We sonic everything now....CHEAP insurance. Charlie ny