Rocker arm comparison

[1964SuperStocker]

I need to replace all studs I believe as there is evidence of the old rockers hitting the studs due to too short of a pushrod. Nothing appears to be bent or broken, and compression check as well as leak down was beautiful.

I'd grab a couple longer ones and see where they put you. Here is one of my only mock up shots. I don't know what stage I was at when I took this picture but close to figuring this out I think.

 

[tenxal]

With the adjustable pushrod, I'm using lightweight checker springs. Pushrod wise I'll probably eng up using trend or Manton .130 wall thickness

Make sure and check that the upper diameter of the pushrod doesn't contact the rocker during the lift cycle....the pushrod major diameter can try to ride up into the cup if it's too close. If it looks fine but you hear any clicking/snapping noises as you turn the engine to set the valves, double check it.

If it does get close, you can get pushrods that have a tapered portion from the major diameter to the top of the pushrod. Most rockers are done for the 5/16" ball ends...but not all of them. Double check this and order the compatable pushrod ends to fit the rocker.

 

[Barry Taylor]

I distinctly remember Ronnie telling me that when using big block length valves correct geometry becomes a real PITA.Sounds like what you're running into here.

I pulled a valve cover but was not able to verify lengths. After talking to roger i feel confident that there 9.100 and 8.900 long. As to Ronnies coversation with Don about running bigblock valves, these are the heads in question. 11/32 Manley pro flo BB valves cut down. When we ran these the first time on a stock stroke motor half way down track on the 2nd pass the motor starts missing popping and i shut it off. After inspection Ronnie finds a bunch of valves backed way off. “With polly locks” He resets em and i make another run and it starts popping before i get back to the trailer. Same thing and were done for the day. I had a Walden stud girdle that i got with these heads and we put em on. After Ronnie fought adjusting valves with this new toy. “Problem solved” These heads will be going on my next motor. Hope thse pictures help!!

 

[63409impala]

Ok fellas, here is the first round of comparisons. The pictures will go in this order so you know what rocker did what. Sadly, the crower rocker has too wide of trunions and does not clear my springs or retainers. I happened to get it to clear on cyl 2 for the test. First is the harland sharp, second is the comp gold, 3rd is the crower.

 

[63 dream'n]

The patterns all look close to identical to me....... I can’t tell if it’s lighting is there an improvement on the third one ....???

 

[63409impala]

Let me enlarge them. Hang on.

 

[63409impala]

The patterns all look close to identical to me....... I can’t tell if it’s lighting is there an improvement on the third one ....???

Hope this is better.

 

[La Hot Rods]

Looks like the one in the center is the shortest pattern to me.

 

[63 dream'n]

I agree that the center looks like it’s the shortest pattern. I believe the third one gets furthest into the center of the valve

 

[63409impala]

Thats the comp gold rocker

 

[63409impala]

Well guys, I just got a crower rocker with a .050 backset and here is the pattern. 9.200 length pushrod. Might possibly try a 9.250

 

[Tim]

Well guys, I just got a crower rocker with a .050 backset and here is the pattern. 9.200 length pushrod. Might possibly try a 9.250

I’m not the expert but from what I was told and shown the travel looks too wide. I played with my adjustable rod for quite some time to get this pattern and was told the shorter the travel the better. You’re getting all the lift with short travel. Somebody correct me if I’m wrong

 

[63409impala]

I'm just happy it's not rolling off the tip of the valve anymore

 

[La Hot Rods]

You will see the pattern get shorter with a longer push rod.

 

[63409impala]

You will see the pattern get shorter with a longer push rod.

I'm not done yet.

 

[Tim]

I'm not done yet.

Do you have an adjustable one to use? Would save a ton of time.

 

[63409impala]

Do you have an adjustable one to use? Would save a ton of time.

Yes I do. Goes from 8.800 to 9.800. I ended up getting the last 8 centerline aluminum rockers from crower today. So I just have to finalize pushrod length, order new pushrods, and I can FINALLY enjoy my car some.

 

[La Hot Rods]

 

[Tim]

James that’s an excellent video!!

 

[Barry Taylor]

Thanks James! I knew you’d come thru with a good video! I learned something new today!