pix
FORDMUSCLE.com FordMuscle Nav
Page 2 3
 

Magnafluxing, Shot Peening, and Pressing Rod Bolts
After finishing the rod beams on my own, it was time to turn the work over to the professionals. To take the rod, cap, and piston assemblies to the finish line, I turned into a spectator while Auggie Steinert demonstrated the rod preparation, reconditioning, and balancing techniques that require experience, training, and special equipment... that's most of them!


Since I was going with ARP Wave-Loc bolts that have a radiused shoulder, it's best to put a chamfer on
each rod's bolt hole. Factory bolts have a 90 degree shoulder.
 
The chamfer will allow the bolt head to sit squarely on the rod. This is
critical for accuracy when torqueing the rod bolts to specification.
     

The magnaflux process is intentionally done after the parting line is removed from the beam. Maganfluxing involves applying a magnetic field to the iron rod, placing it under a UV light, and dusting the rod with iron powder.
 
Cracks will show themselves as purple veins where the powder interacts with the "broken" electromagnetic field that is passing through the part. In our case, all eight rods passed.
     

Now it was time for shot peening then rod beams. Shot peening compacts the metal surface by bombarding it with steel balls.
 
Compacting the rod's grain structure is further insurance to prevent stress cracks from arising. Auggie was careful not to shot-peen recklessly toward any machined surfaces.
     

This rod was removed halfway through the shot-peening operation. The portion of the beam toward the big end has been shot peened. Note the matte finish. All eight rods were processed with the shot-peener.
 
Using a cap grinder, a minimal amount of material is machined from the cap AND the rod mating surfaces for all eight sets.
     

Here's one rod's freshly cut mating surface.
 
Auggie uses a hand file to carefully deburr any sharp edges left from the cap grinder operation. Again, this is performed on all eight rod and cap sets.
     

After applying some lube to the rod bolts and the rod bolt holes, the new ARP Wave-Loc's are pressed into position.
 
By torqueing the nuts to 50 lbs, loosening, then retorqueing to 50 lbs. again, the caps are secured to all eight rods confidently.
     

A hand file across the fastened rod and cap assembly removes any burrs that may cut into fellow rods/caps when the parts are stacked.
 


(
Grinding & Honing, Balancing, and Pressing Pin)

Page 2 3

ARP Wave-Loc Rod Bolts
Good connecting rod bolts are possibly the best investment you can make for increasing the durability of your motor.



On more than one occasion, ARP's patented Wave-Loc bolts have been recommended to me. As opposed to the less expensive knurled shank design, the Wave-Loc's "smooth" interference fit can prevent the stress-risers sometimes caused by diamond knurls cutting into the rod.

See the ARP online catalog for more information.



 


pixblue
pixblue
Tech Archives Project Cars Readers Cars Feature Cars