Profile Picture

REPLACEMENT PISTONS

Posted By FORD DEARBORN 6 Months Ago
You don't have permission to rate!
Author
Message
FORD DEARBORN
Posted 6 Months Ago
View Quick Profile
Supercharged

Supercharged (444 reputation)Supercharged (444 reputation)Supercharged (444 reputation)Supercharged (444 reputation)Supercharged (444 reputation)Supercharged (444 reputation)Supercharged (444 reputation)Supercharged (444 reputation)Supercharged (444 reputation)

Group: Forum Members
Last Active: 6 days ago
Posts: 207, Visits: 48.0K
Greetings to all:  Presently there is a very good and interesting discussion regarding 292 overbore/rotating assemblies but I thought it best to start a new topic for this question.    There has been several discussions regarding 312 cranks and 292 rods used as an assembly. Something I never thought of. I was under the impression the pistons would be custom ordered to allow for proper head trimming for the purpose of achieving zero deck height.   Can a certain amount of stock be safely removed from the top of an off the shelf cast piston such as a Sil-O-Lite?  Thanks if advance, JEFF..........................


64F100 57FAIRLANE500
Rono
Posted 6 Months Ago
View Quick Profile
Supercharged

Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)

Group: Forum Members
Last Active: Yesterday
Posts: 1.2K, Visits: 43.3K
Jeff;

I used a 312 crank with C2AE rods and stock 292 pistons. The block was a .060" over bore which gave me a displacement of 317 cu. in. The pistons were, if I remember correctly, 0.063" out of the bore at the top of the stroke. The pistons were easily milled .063" to get a "zero" deck

Rono

http://www.y-blocksforever.com/forums/Uploads/Images/820681b8-9d4c-46c2-9484-28c5.jpg

Ron Lane

Meridian, ID


FORD DEARBORN
Posted 6 Months Ago
View Quick Profile
Supercharged

Supercharged (444 reputation)Supercharged (444 reputation)Supercharged (444 reputation)Supercharged (444 reputation)Supercharged (444 reputation)Supercharged (444 reputation)Supercharged (444 reputation)Supercharged (444 reputation)Supercharged (444 reputation)

Group: Forum Members
Last Active: 6 days ago
Posts: 207, Visits: 48.0K
That means there IS enough meat on the top of a stock replacement piston to safely allow .063 to be removed. To me, that's amazing information. Wish I knew that when I built my 312 several years ago - thanks Rono..................


64F100 57FAIRLANE500
NoShortcuts
Posted 6 Months Ago
View Quick Profile
Supercharged

Supercharged (2.8K reputation)Supercharged (2.8K reputation)Supercharged (2.8K reputation)Supercharged (2.8K reputation)Supercharged (2.8K reputation)Supercharged (2.8K reputation)Supercharged (2.8K reputation)Supercharged (2.8K reputation)Supercharged (2.8K reputation)

Group: Forum Members
Last Active: 2 Weeks Ago
Posts: 1.3K, Visits: 111.8K
Rono.  I vaguely recall Ted Eaton indicating in an earlier engine build discussion that in using the longer 292 connecting rods with a 312 stroke crankshaft, there is less frictional loading of the piston against the cylinder walls at the bottom of the piston stroke.  Have I recalled that correctly?

IF correct, is that why you used the 292 length rods in you supercharged engine build OR were you simply seeking to use an available production connecting rod that was stronger than the 312 ECZ rods.

Do I recall that you used flat top forged Probe pistons from John Mummert in combination with 5750-471 cylinder heads for your supercharged engine build?

An .063 cut off the tops of your pistons was only about 1/16 of an inch of material removal.  That does not sound like a lot of material to remove . . .

Thanks for sharing!  Smile


NoShortcuts
a.k.a. Charlie Brown
near Syracuse, New York
Ted
Posted 6 Months Ago
View Quick Profile
Co-Administrator

Co-Administrator (9.0K reputation)Co-Administrator (9.0K reputation)Co-Administrator (9.0K reputation)Co-Administrator (9.0K reputation)Co-Administrator (9.0K reputation)Co-Administrator (9.0K reputation)Co-Administrator (9.0K reputation)Co-Administrator (9.0K reputation)Co-Administrator (9.0K reputation)

Group: Administrators
Last Active: 6 days ago
Posts: 5.9K, Visits: 93.8K
As a general rule, 0.200” is the minimum accepted value for piston deck thickness for a normally aspirated application.  Many cast pistons have decks that are 0.400” thick or more which gives plenty of room to cut the piston tops down.  The only caution here is to be aware of where the top ring placement is so that the top ring does not get too close to the piston top.  If it gets too thin there, then the ring land will break.

Lorena, Texas (South of Waco)
Rono
Posted 6 Months Ago
View Quick Profile
Supercharged

Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)Supercharged (2.3K reputation)

Group: Forum Members
Last Active: Yesterday
Posts: 1.2K, Visits: 43.3K
Charlie;

The supercharged motor I built uses Mummerts stroker kit that includes forged I beam rods and Probe pistons. On that build I asked John to mill flat the 10cc domes that were on those pistons to reduce compression. The motor build where I used the 312 crank and the 292 rods was the build prior to the supercharger build and is in the 56 Customline I have. At the time, I did not know that there would be reduced friction with that crank and rod combination. 

http://www.y-blocksforever.com/forums/Uploads/Images/820681b8-9d4c-46c2-9484-28c5.jpg

Ron Lane

Meridian, ID


2721955meteor
Posted 6 Months Ago
View Quick Profile
Supercharged

Supercharged (1.4K reputation)Supercharged (1.4K reputation)Supercharged (1.4K reputation)Supercharged (1.4K reputation)Supercharged (1.4K reputation)Supercharged (1.4K reputation)Supercharged (1.4K reputation)Supercharged (1.4K reputation)Supercharged (1.4K reputation)

Group: Forum Members
Last Active: 4 days ago
Posts: 660, Visits: 69.7K
i just had heads off a 312, found the composet head gasket is aprox .040 thick at fire ring,so on early shimy gaskets 1 would  have 25 to .030 more room, with jober pistons usually lower idistance pin to top of piston .the 312 i speak of the piston came right to the top of the block.(it has 292 rods.)  have had a truck 292 apart had 312 con rods pistons well below the deck,the312 rods look a lot stronger. ted could  most likely have experience in this aria .
FORD DEARBORN
Posted 6 Months Ago
View Quick Profile
Supercharged

Supercharged (444 reputation)Supercharged (444 reputation)Supercharged (444 reputation)Supercharged (444 reputation)Supercharged (444 reputation)Supercharged (444 reputation)Supercharged (444 reputation)Supercharged (444 reputation)Supercharged (444 reputation)

Group: Forum Members
Last Active: 6 days ago
Posts: 207, Visits: 48.0K
Thanks to everyone for the excellent information, JEFF.................


64F100 57FAIRLANE500


Reading This Topic


Site Meter