MR V LIMITED/MODIFIED-4.500 ROD
Refer to Degreeing Instructions and Installation Instructions supplied in the cam box or our website for proper setup of your new camshaft. Mr.Velocity™ cams have a rapid acceleration rate and will require the use of GP8250-2 Billet Lifters to insure durability. We recommend welding the lifter bores on your block and “chamfering” your lifter bore approximately .030”. Frequently check the condition of the valve spring retainers, lifters and valve springs. It is a good idea to change your springs, retainers and lifters at every rebuild. In order to achieve controlled valve float and maximum performance at high RPM, it is ESSENTIAL to properly setup your valve springs. Improper set-up of your valve springs could result in damaged parts inside your engine and lost performance. See recommended spring pressure specs for the proper setup.
Ignition timing should be referenced when the right leg of the coil is lined up with a line about 3/8” from the leading edge of the magnet on the flywheel.To find the exact line on the flywheel, you must use a timing light. Check installed height WITH the lower retainer on the valve. Check the spring pressure WITHOUT the lower retainer, spring only. The valve spring seat will require cutting to achieve the proper amount of pressure. Be careful to not cut the block too much! On restricted engines, we have found carburetor metering holes of .056” (big) and .026” (small) give the best performance. On unrestricted engines, we have found carburetor metering holes of .054” (big) and .026” (small) to give the best performance. On super stock engines, an upper spring retainer must be used.We have found the 314 Tillotson to give the best carb performance.