I have a 73 429 that has .30 over kb flat tops. And its all balanced with a 4x4 cam in it. I can't remember the lift or duration. its not to extreme. The 73 dove heads needed completely gone thru so I got a set of 68 c8ve heads that have screw in arpstuds with push rod guide plates. And I bought 8:55 length hardened push rods and 1.70 ratio full rollers for it. And it runs worse than before. It sounds good at an idle and revving at an idle. But with a load on it it is gutless. I don't know if I have the wrong ratio rockers or wrong length pushrods or what I don't know if anyone has done somethin like this and would know what is goin on with my engine. People say with the setup I have it should run like a bat out of hell. and just to note it ran good before all I did was put a new intake and heads. No cam to crank timing changed or anything like that. Thanks

 

so i guess a hyd cam. Have you set you hyd lifter lash correctly. let idle and run through valvetrain. meaning to back off rocker arm until it starts to tap or start clicking. then tighten up about a 1/2 turn. ticking should go away. spec on cam would be nice so to help with better answer. on pushrod length why did you change. have you done a pattern check on valvestem. meaning get a black marker and mark the top of each valve tip and see what pattern showing on top of valvestem after rotating the crank once. the roller tip of rocker arm will rub on top of valvestem and show you your pattern. if pattern in center your good to go. but if not need to lengthen or shorten to get pattern in center of valvestem. talk to you later.

 

Thanks. I was told that you do not adjust Fords like Chevys. They all said do it while not running the engine. But since those heads have had studs put in is that why? By the way they are bottle neck studs I dunno if that matters or not?

 

The first thing I'd do is get rid of the 1.7 rockers they will never produce good geometry in a Ford head. Second get rid of those studs. You might need to mill the stud bosses down some to get the geometry right. Studs come in a cupple of lengths for big blocks though.

 

To adjust stud mounted rockers,turn the engine by hand(choose a cylinder)until the exhaust valve starts to open(pushrod moves up).Adjust the intake valve to zero lash plus a half a turn.Rotate the engine again until the intake valve is almost closed.Adjust the exhaust valve to zero lash plus a half turn.The goal is to gain between .020-.040 between the lifter plunger and the plunger retaining clip.That's lifter preload.Of course you should check rocker geometry.I run Crane's 1.73:1 rockers.My buddy uses 1.70:1 on his 460 and hasn't had any issues in years.I did not have the stud bosses milled either.Stud length especially thread length is important.Cam lift also plays a part.

 

you cannot use the bottle neck studs with aftermarket roller rockers. you will never get them to adjust properly. you have to use full lenght studs meant for a 460 and the locking type adjsuting nuts and adjust your rockers as stated in previous post.

rgds
Mike

 

The OP said he has ARP studs.Could be the wrong length and/or not properly adjusted.And OP,the adjustable rockers adjust just like the canted valve Big Block Chevy engines from the 70's.But as stated,you need all of the right components to work together.There is measuring and trial fitting involved.Cam specs would also help.

 

. I have the same setup except I have bottle neck studs. Does that matter? And how are the rockers gonna stay lined up on the value stem

 

Hutch, the pushrod guides keep your rocker arms from straying from where they should be.

 

In your OP you stated that you had "arpstuds".Like Mcdonaldm said,you can't use OEM style studs(bottle neck studs) with adjustable roller rockers.I use ARP 100-7101 studs.I chose those because of the thread lenght for the rocker arms.They may or may not work with your combo.I have had several big block Chevy engines and the 460 Ford heads are a similar valvetrain design.Rocker geometry is important.Depending on the cam profile,there are several areas where contact or premature wear can occur.Do it right now so that you're not taking the heads off to replace the guides,valves or even broken parts.Converting to adjustable rockers is not a bolt on deal.If you've been running the engine with the OEM studs and roller rockers,you should check the valvetrain parts for damage.Also,make sure your lifters are intact.Loose rockers cause the pushrods to hammer the lifter plunger which in turn causes the lifter come apart.