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Discussion Starter #1
I am building a 289 with HiPo heads. The heads have been milled to increase the compression and a ton of porting has been done. Now the roller rockers do not sit in the center of the valve ends. I checked the push rod lengths and they are all about 0.250 short. If I buy longer push rods, the studs don't have much thread left to adjust and tighten...maybe 5 threads.
What to do? Do I leave the roller off centered or fix this issue some how?
Thanks for the help.
 

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Did you really mean to say the pushrods are 1/4" too short?

I'm thinking you meant to say .025". That's a LOT of planing. I hope the intake ports were raised accordingly. Have you accounted for valve clearance? Wouldn't want those bad boys hitting the top of the pistons.

Back to the original question, Unless something else has been done, you should have more than 5 threads when done, but that's enough. I don't see why you'd want longer pushrods, though, if you planed the heads, the pushrods should be shorter, by the exact amount you cut off the heads.

I used 7/16" BOSS 302 studs on my 289HP, which meant I had to switch to 5.0 rockers (which are more stable anyway).

Are you still using the in-head slots or did you change to guide plates?
 

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Discussion Starter #3
Thanks for the speed response,
I used the correct length tool and I had to increase the length by 0.250 to get the roller to sit in the center of the valve stem.
I bought this engine from a vintage car shop about 15 years ago. It came out of a wrecked Cooper Indie car in 1964. I had it rebuilt to run on the street. The compression ratio was about 12 to 1. It had many upgrades including 0.030 over forged pistons, roller rockers, aluminum flywheel, Cobra intake, double pumper holly and so on and on.
The builder tore it down and magna fluxed everything. It had a cracked crank, but everything else seemed fine to the builder. The block had a bit of moisture in one cylinder and etched it at the bottom of the bore a bit so we bored it to 0.040 over and put in a new set of forged pistons. We used a Babe Erkson cam to make it "rumble" a bit. I had noticed that the pushrods were dented and scuffed before it was rebuilt, so I opened it up and sure enough they needed to be replaced. I purchased a set of stainless 1.6 to 1 Comp Cam lifters and when I installed them, I noticed that the roller was way inside so the lifters were way too short. I bought the adjustable tool and checked it this morning. It took 5 complete rotations or 0.250 to get the roller centered in the valve stem. That pushed the rocker up so far that I only have about 5 threads left to lock the rockers.. So what to do? Longer screw in studs or leave it like it is and hope at 7K the roller doesn't fall off the valve stem.
Your thoughts?
 
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