[twisted91]

i've got a sbc 355 with a crane 100112 hydraulic camshaft. the heads are rebuilt 993 heads with 202/160 valves and the springs were setup for comp 305h camshaft which is similiar to my crane cam. but my problem is on #8 cylinder i keep bending pushrods. they are melling pushrods. which aren't hardened. but also noticed where the pushrods go into the head the guide in the head is a little wore. so it has a little side to side movement but i am using slotted rocker arms. so the rocker arm stays on the valve. it will run good but as soon as i rev up to a higher rpm it goes to bending pushrods. my question is could hardened pushrod prevent this or go with a wider pushrod to keep it more aligned. it is driving me crazy cause i only have driven the car about 200 miles on new rebuild and want to get on it to see how strong it is. any help would be appreciated.

[GMC boogie]

One problem I see is the use of two methods of alignment. Either use the pushrod slots in the 993 heads and non self-aligning rockers or open up the slots and use the self aligning rockers.

Make sure your springs are not binding or the retainers making contact with the seal/guide boss.

[RPM]

You can only have one way to align the push rod. The slot in the head, a push rod guide plate or a rail type rocker. If you have a push rod binding up that will cause it to bend. When you adjust the valve, with the valve closed you should be able to spin the push rod.
Now as GMC boogie says you have to make sure the bottom of the retainer is not contacting the top of the guide or seal at full lift. Also a rocker could be binding on the stud at full lift. All of this is going to be hard to check on the engine with it in a car.

[twisted91]

i found out that one of the rocker stud was bent which threw everything out of alignment. ran the car so far so good but anything is possible thank ya'll for the help.