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I have a 69 Bronco with a rebuilt 302. 302 is a '73 and I have early model 289 high compression heads. Pistons and connecting rods are basically stock. Seem to have lots of oil pressure and flow. Heads redone with rebuild an I used basically stock valves, guides, springs... I 've put an RV low end torque cam in it (from Melling) that is pretty mild. I went to roller tiped rockers and I have hydraulic lifters in it. Since doing the rebuild, I've got a lot of valve train noise. Nothing dramatic, you can just hear all the valves working. I've listened to other rebuilds and they seem pretty quiet.
Any ideas? Is this normal? I've adjusted the valves precisely per spec repeatedly and it doesn't change the noise level. I've put a fair number of miles on the engine since rebuild and there dosen't seem to be any issues. Just makes me nervous that it will fail early.
Matt, I'm wondering if you need pushrod guide plates with those roller-tip rockers. Ford went to a rail type rocker arm in 1966 which kept everything centered. I don't think your cam is radical enough to worry about needing screw-in studs but it may be an option for you to consider because you'll need them if you decide to use guide plates.
If those roller tips are moving all over the valve stem I'm afraid its just a matter of time before they contact a keeper.....a dropped valve and blown engine is the next thing that happens. Just something for you to think about.
Matt, I've built alot of fox bodied 5.0 engines and in almost all instances roller rockers do make a little more noise than a stamped designed rocker. Guide plates are a possibility but also check to make sure your lifters are pumping up all the way. If you got them [lifters] at an auto parts store {advanced,auto zone,pepboys,etc.etc.}, this could possibly be the issue. Order them from Ford Racing or Ford Motorsport. Those rockers should be self-adjusting. Good rule of thumb, tighten them until they make niose then back them off a quarter turn; intake,intake,etc./exhaust,exhaust,etc. Also, assuming that your cam was ground right at the lobes, check the length and staightness of your pushrods. A can of Marvel Mystery oil can take the shellacking off of a lifter that the chamfering holes are clogged up on, not letting it pump up all the way. I've also soaked them in transmission fluid for a night to help pump them up before I installed them. With the valve covers off and engine idling warm, make sure you have good oil coming out of the rods, take a stick and put it tight in your ear and up against the rocker one at a time to see which one or ones are making the most noise. Stop engine and bump it or turn the crank until that valve comes up all the way, then take a feeler gauge in between the roller tip and the pushrod. This could help tell you whether the lifter is pumping up all the way. I don't know how much lift or duration your cam has, but if it's not TOO extemely big, you shouldn't have any piston slapping issues. Good Luck!!! chad76