View Single Post
  #11 (permalink)  
Old 06-13-2010, 06:17 AM
Barry_R Barry_R is offline
CC Member
Visit my Photo Gallery

 
Join Date: Jul 2003
Location: West Bloomfield, MI
Cobra Make, Engine:
Posts: 717
Not Ranked     
Default

Rick
My 95 is a generic statement - the most important one is to follow the hone process. The 95 pound number is a good one for iron block, alluminum head, traditional fastener length (non-Shelby) FE combos - like the vast majority of folks are going to have.

The factory 427 engines had much higher torque numbers of over a hundred. Your longer fasteners are going to require a lower number to reach a given amount of stretch. I have gone to a lower torque value because I felt that the aluminum heads were growing and crushing the gasket. Proper use of washers as Keith noted helps reduce the bolt hole damage a lot. Blue Thunder heads have pressed in bolt seats which eliminate the problem entirely.

OEM head gasket and fastener combinations are a sealing system defined after extensive lab testing. The fastener clamp load is determined by torque/angle and/or stretch with reduced cross section fasteners being common to maintain an even load. The MLS gaskets they use are designed to function as springs allowing vertical head movement without losing bead contact and sealiing. They also have gone to floating decks where the cylinders are not interconnected and no combustion sealing ring in the gasket.

Unfortunately we cannot draw a fair comparison between the gasket sealing technology they use now and our ancient stuff. Adopting only a part of the system does not guarantee the results. The glue you're using on the head gaskets will help make up for any fluid loss or migration between the aluminum block and aluminum heads - I have one pretty good builder/friend who uses copper coat on his aluminum/aluminum engines but nothing on the iron block combinations. Just because I don't like it does not mean it won't work.....
__________________
Survival Motorsports

"I can do that....."



Engine Masters Challenge Entries
91 octane - single 4bbl - mufflers
2008 - 429 cid FE HR - 675HP
2007 - 429 cid FE MR - 659HP
2006 - 434 cid FE MR - 678HP
2005 - 505 cid FE MR - 752HP
Reply With Quote