The Ford Barn

Rowdy · 10-31-2013, 11:03 AM

I have tried the search for info, but did not get any results. I looked at an engine taken out of a truck yesterday and it has heads marked 81-A. I have not seen this marking before, so I am curious as to what years these were made and the compression ratio. Also were these heads for flat top pistons or dome to pistons? Thanks Rod

MuskegonFlatheadFan · 10-31-2013, 11:53 AM

good stuff here;
http://www.vanpeltsales.com/FH_web/f...85to100mid.htm

flatjack9 · 10-31-2013, 12:08 PM

They would be 24 stud heads introduced in 1938 for dome top pistons.

Rowdy · 10-31-2013, 12:34 PM

Thanks Jack, just the info I needed. Figured they were before 41 because it has a helmet dist. Also has a Stromberg LZ carburetor, which is why I will likely buy it. Hoping I can keep the carb and break even in the rest. The carb may be a match to my other one which will be great on a slightly warmed up 37 21 stud. Rod

dude · 10-31-2013, 12:38 PM

as I remember they had much the same dimensions as a 59A head

flatjack9 · 10-31-2013, 05:22 PM

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I think they might be a little smaller. Seems to me Ron recommends them on a 59A.

uncle max · 10-31-2013, 05:25 PM

Valve pockets will need to be cut if using on a 59-A.

Ol' Ron · 10-31-2013, 05:33 PM

Yes these are alittle smaller than the later heads due to the relocation of the valves higher in the block. You'll have to use a die grinder to make clearance for the valves. Not much need be removed.
Milling these for .050" piston clearance will increas the CR of a 59 or 8ba series one point . Yes by plunging a water hole you can run them on an 8ba.

Rowdy · 10-31-2013, 10:05 PM

Thanks Guys. I hope the block is not a boat anchor when I have it checked out later this winter. Rod

Rowdy · 11-08-2013, 09:44 AM

I scraped off the grease on the back of the block yesterday and it is marked 59. Also it has A474. Is there any signigance to the A474 on the back of the block? Thanks Rod

ford38v8 · 11-08-2013, 12:42 PM

Those additional characters have never been identified, and are assumed to be mold or batch numbers. The large 59 is significant, I'm sure you know what that means.

Rowdy · 11-08-2013, 12:58 PM

I was happy to see the lage 59 and with the 81-A heads could point to some other goodies inside if they invested the money into the heads to enlarge the valve pockets to use them on the 59 block. Will be pulling the heads next week and try to look cracks and such. Engine is stuck, but since it will have to come apart anyway, thats not a huge issue. Also appears to have an 11" clutch as the pressure plate can not be removed through the back of the bellhousing as it will not fit. I think a 10" would come out without removing the pan. This one will not. Rod

10-31-2013, 11:03 AM	#1
Rowdy BANNED Join Date: May 2010 Location: Gothenburg Nebraska Just off I-80 Posts: 4,893	Engine with Heads Marked 81-A I have tried the search for info, but did not get any results. I looked at an engine taken out of a truck yesterday and it has heads marked 81-A. I have not seen this marking before, so I am curious as to what years these were made and the compression ratio. Also were these heads for flat top pistons or dome to pistons? Thanks Rod __________________ Do the RIGHT thing - Support the H.A.M.B. Alliance!!!!

10-31-2013, 11:53 AM	#2
MuskegonFlatheadFan Senior Member Join Date: Sep 2011 Location: Muskegon, MI Posts: 252	Re: Engine with Heads Marked 81-A good stuff here; http://www.vanpeltsales.com/FH_web/f...85to100mid.htm

10-31-2013, 12:08 PM	#3
flatjack9 Senior Member Join Date: May 2010 Location: Oshkosh, Wi Posts: 4,526	Re: Engine with Heads Marked 81-A They would be 24 stud heads introduced in 1938 for dome top pistons.

10-31-2013, 12:34 PM	#4
Rowdy BANNED Join Date: May 2010 Location: Gothenburg Nebraska Just off I-80 Posts: 4,893	Re: Engine with Heads Marked 81-A Thanks Jack, just the info I needed. Figured they were before 41 because it has a helmet dist. Also has a Stromberg LZ carburetor, which is why I will likely buy it. Hoping I can keep the carb and break even in the rest. The carb may be a match to my other one which will be great on a slightly warmed up 37 21 stud. Rod __________________ Do the RIGHT thing - Support the H.A.M.B. Alliance!!!!

10-31-2013, 12:38 PM	#5
dude Senior Member Join Date: May 2010 Location: Kansas Posts: 334	Re: Engine with Heads Marked 81-A as I remember they had much the same dimensions as a 59A head __________________ [QUO[/QUOTE]no matter where you are,or where you're at, there you are...

10-31-2013, 05:22 PM	#6
flatjack9 Senior Member Join Date: May 2010 Location: Oshkosh, Wi Posts: 4,526	Re: Engine with Heads Marked 81-A Sponsored Links (Register now to hide all advertisements) I think they might be a little smaller. Seems to me Ron recommends them on a 59A.

10-31-2013, 05:25 PM	#7
uncle max Senior Member Join Date: May 2010 Location: SLC Utah Posts: 798	Re: Engine with Heads Marked 81-A Valve pockets will need to be cut if using on a 59-A. __________________ RIP Tyler... My Son, Helper & Best Friend. Feb '78 to Father's Day '10. www.97-express.com ~ [email protected]

10-31-2013, 05:33 PM	#8
Ol' Ron Senior Member Join Date: May 2010 Location: Chester Vt Posts: 8,859	Re: Engine with Heads Marked 81-A Yes these are alittle smaller than the later heads due to the relocation of the valves higher in the block. You'll have to use a die grinder to make clearance for the valves. Not much need be removed. Milling these for .050" piston clearance will increas the CR of a 59 or 8ba series one point . Yes by plunging a water hole you can run them on an 8ba.

10-31-2013, 10:05 PM	#9
Rowdy BANNED Join Date: May 2010 Location: Gothenburg Nebraska Just off I-80 Posts: 4,893	Re: Engine with Heads Marked 81-A Thanks Guys. I hope the block is not a boat anchor when I have it checked out later this winter. Rod __________________ Do the RIGHT thing - Support the H.A.M.B. Alliance!!!!

11-08-2013, 09:44 AM	#10
Rowdy BANNED Join Date: May 2010 Location: Gothenburg Nebraska Just off I-80 Posts: 4,893	Re: Engine with Heads Marked 81-A I scraped off the grease on the back of the block yesterday and it is marked 59. Also it has A474. Is there any signigance to the A474 on the back of the block? Thanks Rod __________________ Do the RIGHT thing - Support the H.A.M.B. Alliance!!!!

11-08-2013, 12:42 PM	#11
ford38v8 Senior Member Join Date: Jul 2011 Location: SF Bay Area Posts: 6,641	Re: Engine with Heads Marked 81-A Those additional characters have never been identified, and are assumed to be mold or batch numbers. The large 59 is significant, I'm sure you know what that means. __________________ Alan

11-08-2013, 12:58 PM	#12
Rowdy BANNED Join Date: May 2010 Location: Gothenburg Nebraska Just off I-80 Posts: 4,893	Re: Engine with Heads Marked 81-A I was happy to see the lage 59 and with the 81-A heads could point to some other goodies inside if they invested the money into the heads to enlarge the valve pockets to use them on the 59 block. Will be pulling the heads next week and try to look cracks and such. Engine is stuck, but since it will have to come apart anyway, thats not a huge issue. Also appears to have an 11" clutch as the pressure plate can not be removed through the back of the bellhousing as it will not fit. I think a 10" would come out without removing the pan. This one will not. Rod __________________ Do the RIGHT thing - Support the H.A.M.B. Alliance!!!!