Windsor 289-302-347 Alloy 6061 T6 Main Stud Girdle

6061 T6 Alloy Ford 289-302-347 Windsor Main Stud Girdle ( PT-347MSG )

Pavtek has produced a bolt-on Alloy Main Stud Girdle for Ford Windsor Engines. This girdle requires no costly aftermarket main cap fitting. Performance engines suffer from considerably higher stress loads compared to normal passenger car engines. Nitrous oxide injection, superchargers or turbochargers can more than double the normal amount of stress placed on main bearing caps, fasteners, and cylinder block main webbing. Aside from the power adders competitive motorsports such as drag racing, circle track or roadracing can have an equal effect on a modified or stock engine. These internal stresses can cause the main bearing caps to move or walk from side to side. Movement is then transferred to the free end of the main cap bolts or studs. Eventually the threaded bolt holes in the block crack. Main bearing cap walk can allow the bearing inserts to spin, the crankshaft to break, or the main webs to crack and fail. Due to the close proximity of the Main Stud Girdle to the crankshaft and rods it also does a very good job of stripping oil off of the crank.

With a superior strength-to-weight ratio 6061 T6 aluminum is more expensive than steel but much more effective at dampening harmonics, which is the leading cause of main cap walk and block failure. The lightweight 3/4" thick Main Stud Girdle evenly distributes load and dampens harmonics by bolting the main cap studs together to create a super strong rectangular cage. The brace nearly doubles the main web support area in the engine. The added strength and rigidity assists to  eliminate main cap "walk" or movement. Securing the loose end of the main studs provides stability unequaled even by a 4-bolt main block. Additionally, a production 2 bolt block strengthened with a Pavtek Main Stud Girdle is an economical alternative to an expensive 4-bolt aftermarket block or steel cap conversion.

PT-347MSG - This Main Stud Girdle requires the use of ARP main studs Part # 154-5408 for their additional length. ( Conventional Windsor main studs are too short to be used successfully ) In addition one 12 point nut will also be needed ARP300-8303 for the stud directly under the oil pump.

These Arp products are available from Pavtek.

Pavtek main stud girdles also come with fitting instructions. 

Note a steel girdle utilizes spacers placed on top of the main caps to achieve clearance between the girdle and main caps. Our girdles are .750" thick and the clearance between the main caps and girdle is machined into the girdle. This way the main caps, studs and girdle are braced in the best possible way for the best possible increase in strength to your bottom end.