Hello, I have 72 MAV with a 302. What size push rod length do I need? I’m using the rail rockers (CAT roller tip) Right now I cannot get any preload when I adjust to 20 foot pounds.I increas to 23 foot pounds with no luck, I can still twist the push rods a little bit. Thanks Tony 805 258-9824
I'm assuming your heads have the factory positive stop, set & forget studs??? If that's the case, unless actually on a lobe, it's normal to be able to spin the push rod as the plunger inside the lifter compresses... Main concern would if the nut is at spec and there is still some lash, in that case you need longer push rods... Ford supplied service push rods that were .060 longer or shorter but most aftermarket vary by approx .100 between lengths... Though it isn't mentioned in any manual I've seen, you can still sort of check clearance the same way as the fully adjustable rockers... Tighten the nut till the clearance is at zero, then note how many turns it takes to torque the nut to spec, hopefully it will be some where 1/2 and one full turn max... BTW most of the aftermarket rockers are designed to be used with a fully adjustable valve train and not really meant to be used on a positive stop type stud... Of course with some push rod length juggling it can be done... If I remember correctly, the non roller 302 push rod length is 6.80" so if yours are too short you'll prob need a 6.90... As already mentioned, a push rod length checker would go a long way in solving your issue...
Thanks for all the info. The roller tips from CAT are for rail rockers with non-adjustable. I'm trying to see if there 2 different lengths. 1 for non-adjustable, 1 for adjustable. Tony 805 258-9824
I dug out a '02 Ford Racing catalog and it does state the 6.80" length are for "non-rail" applications and that a 6.90 is used for stamped steel and most roller rockers... The part no for these is M-6565-N332... Sooo if those are what you have and are too short, you'll have to check some place like Summit that has about any length you'd like(again in .100 increments)... BTW those two lengths are the only ones listed for a non roller 302...
