Solutions? Rockers too high.

Our '69 429 rebuild is moving right along, at the point of determining pushrod length. Cam is a Comp 34-235-4 (Xtreme 4x4 = 262/270 @ .006, 218/226 @ .050, .513/.524 lift, 111 LSA, 107 ICL), the lifters are standard rebuilder stuff, rocker studs are standard 7/16" BBC rebuilder stuff, rockers are Procomp rollers, guideplates are Comps for 3/8 pushrods. All going on D0VE heads w/ the stock valves reinstalled, have mild cleanup pass on the decks, the block is very close to zero deck, and running standard rebuilder .040" thick head gaskets. Machinist did not realize we were going to run guideplates, and did not machine the stud bosses.

Roller tips are hitting valve tips slightly to exhaust side with the rockers positioned all the way down against the shoulder on the studs. They should be a little lower yet to move the pattern inward over the center and slightly toward intake side of tips. We can't get it, rockers are bottomed on stud shoulder.

We should machine the stud bosses down at least same thickness as guideplates, but my buddy already has the heads torqued down and doesn't really want to pull everything back apart, so looking for alternatives.

I am thinking we can chuck up the studs in the lathe and machine the shoulders down a little lower, making the bases of the studs a little thinner, similar to how the stock studs are made. Would certainly be cheaper and quicker than tearing it back apart to have the bosses machined, i.e. wasting a pair of head gaskets etc. And with this mild setup we don't really need the extra meat in base of the new studs, should be able to get away with taking them down to same thickness as the oem '69 studs.

opinions?

Pull the heads and do it right !!! Why cause other problems ???

Plus consider ditching the Procomp rollers, they are nothing but trouble.

This seems to be a common issue...........do it right the first time and don't look back!!!

You won't waste the head gaskets,you can reuse them,same as a retorque. If ya did'nt put some kind of glue on the intake gasket,you can probably reuse it. Like Dave said, do it right.

Your engine is NO PLACE to skimp. Do it right or you'll be pulling the hair out of your head wishing you had. Your taking a BIG gamble by doing this, its a gamble you don't want to lose. It might not be what you want to hear, but just do it and be glad you did. If not then I wont stop you, you'll figure it out later when it comes apart on you.

Not to be an @$$ or anything.

Cut the stud boss down about 3/16" and put a proper ford stud in it[1.900"] .

You can buy a stud boss cutter for around $45.00 and cut them down with a drill, Go slow with a vacuum and it should be fine. Just check the depth of the hole with a set of 6 inch calipers, and go slow.

Did I say take your time and go slow................ ?

I would also nix the pro comp rockers. It will be much easier to get the witness mark on top of the valve stem right with a correct Ford body rocker.

That way everything will be lovely and you wont be cussin later and spending more Dollar's.

R&R the heads and do it RIGHT! Machine the rocker stud bosses down like Lem said. There's a several other things wrong with your build, but I won't go there. Please don't be lazy, and at least do this correctly.

Uncle Charlie

Unfairadvantage wrote: Cam is a Comp 34-235-4 (Xtreme 4x4 = 262/270 @ .006, 218/226 @ .050, .513/.524 lift, 111 LSA, 107 ICL), the lifters are standard rebuilder stuff, rocker studs are standard 7/16" BBC rebuilder stuff, rockers are Procomp rollers, guideplates are Comps for 3/8 pushrods. All going on D0VE heads w/ the stock valves reinstalled, have mild cleanup pass on the decks, the block is very close to zero deck, and running standard rebuilder .040" thick head gaskets.

Roller tips are hitting valve tips slightly to exhaust side with the rockers positioned all the way down against the shoulder on the studs. They should be a little lower yet to move the pattern inward over the center and slightly toward intake side of tips. We can't get it, rockers are bottomed on stud shoulder.
opinions?

It sounds to me as though you think your valve train geometry is incorrect because the roller tip is a little bit "outside of center" on the valve tip. This is not a very accurate way to determine and establish valve train geometry and it may very well be possible that by lowering the rocker on the stud that you are moving things the wrong direction.

Incidentally, you did not say WHEN the roller is on the outside of the valve tip nor did you explain the sweeping action across the valve tip as the rocker arm moves through its radial sweep, so I don't see how we even have a crystal clear picture of your current situation. Also, I am not familiar with ProCrap rocker arms but if they use the BBC rocker silhouette and simply call that a Ford 429/460 rocker then the roller tip will be 0.030" long relative to the BBF valve train layout. This is not in-and-of itself a matter of issue in a mild combo such as yours but it might very well explain why your roller tip is outboard of center (0.030" long combined in conjunction with erroneous geometry evaluation)....and make you think that you need to lower your rocker arms further down on the studs.

We have built countless high performance D0VE-headed 429/460 engines and even more than countless D0VE head conversions where establishing valve train geometry was a necessity. In 100% of the cases where 1.900" valve springs were utilized, we did not--ever--need to mill down the stud bosses for clearance. You stated that you are using the OEM valves which leads me to believe that you have a 1.820" installed valve spring height. If this is the case, then I have indeed run into your scenario where the rockers (some rocker brands, not all brands) might bottom on the rocker stud, but it was close enough that I was able to circumvent disassembly buy installing 0.080" lash caps and 0.050" longer pushrods....but I am not suggesting you simply go do the same, as you first need to correctly evaluate your valve train geometry.

Paul