d. and f. performance logo

Preparing Your Rotating Assembly

Prepping the rotating assembly by balancing,setting up the proper bearing clearances, proper pushrod length, enough piston to valve clearance and using the proper finish on the cylinders are all necessary to create a lasting combination--

Don't forget to join us onFacebook logo our facebook page

click here to enlarge
checking connecting rod housing bore size

--all rod housing bores, new or used, are checked for roundness and size and redone if they are not within spec-

click here to enlarge
checking crankshaft end-play

checking and setting thrust clearance is an important part of the assembly-too little will create heat and wear the thrust surface of the crank

click here to enlarge
checking hone finish with a profilometer

-making sure that your hone finish is within the parameters of where it's suppose to be with a surface gauge insures a long lasting finish for the rings-

click here to enlarge
Sunnen crank shaft balancer

-balancing becomes necessary when the components being used are a different weight than the original components or if the assembly is new and hasn't been balanced previously-

click here to enlarge
Sunnen rod reconditioner

-with 2 very accurate Sunnen gauges, one is setup to check the housing bores of the rods and the other is set to the size of the crankshaft rod journal for the ease of checking the bearing clearance w/o resetting the other gauge-

click here to enlarge
crank polishing fixture

-prior to the assembly, checking cranks for any small scores or scratches is well worth the time spent and then a light polishing will ensure it's ready to go-

click here to enlarge
checking main bearing clearance

-checking the main bearing clearance after the mains have been align-bored is a necessity-even though all the housing bores are the same size there is often some thickness differences from bearing to bearing-nothing should be overlooked when doing preassembly checking-it only takes one item to be overlooked for a problem to develope-

click here to enlarge
adjustable pushrod will help find the correct length for the best rocker geometry

-adjustable pushrod and checking spring allows you to try a couple of different lengths to help you choose the correct one for the best rocker geometry-

click here to enlarge
checking valve to piston clearance

-if you're using a large or aggressive camshaft, you might want to check the clearance between the valve and piston-easiest and most accurate way is with light checking springs and a dial indicator and pushing the valve down to find the closest point-- click here to enlarge
fly cutting pistons for valve clearance

-after finding that you are coming up a little short on the valve to piston clearance, flycutting the piston reliefs will be necessary to help you reach that long lasting combination-- click here to enlarge
checking connecting rod bolt for proper thread stretch to insure proper torque

-torquing the rod bolts to the proper stretch will keep the fastener tight-

click here to enlarge
checking ring gap

checking ring gap is a vital part of the engine building operation-the ring gap is determined by the usage, whether it's NOS, Forced Induction or just N/A operation, each specific load will have it's own gap dependent upon the heat deilvered and the bore size-

click here to enlarge
degreeing camshaft

-degreeing a camshaft to the correct intake center or at least knowing what centerline you are installing the cam at, becomes a very helpful tuning element to move the power curve, either up or down, to put the power where the car needs it most-

click here to enlarge
checking connecting rod for straightness and length

-old but invaluable gauge for comparing rod length from one rod to the next and also for checking connecting rod straightness-

click here to enlarge
checking surface finish with a profilometer

-making sure that the surface finish on heads and blocks is smooth enough for the MLS gaskets is critical for the sealing effect