Not sure if you're picking up what I'm laying down
Hope this helps
Hope this helps
Broke a pushrod, looking for advice
- Thread starter 7t500
- Start date
7t500
Well-Known Member
I understood where you were going with it. I thought we cleaned up the ID well but it's possible we weren't thorough enough or made a mistake... we are both human, for better or worse
You could check the other pushrods and see if there's signs of not being fully seated. (Light between cup and pushrod tube end)
We're all human. That's why you're asking people that may have made the same mistakes before 
7t500
Well-Known Member
If I were planning on keeping them, I would definitely do that... I'm going to order some this time, probably Smith Bros. Glad to hear I'm not the only one that makes mistakes! I've definitely had my share... some I dont want to even admit!
7t500
Well-Known Member
Now, time to game plan! I'm thinking new cam/lifters for sure. I'm tempted to do heads, which have been on the wish list for quite some time...
What does everyone think? Is it worth re-using the 906 heads and get a bigger cam or am I at it's upper limit for flow already? Cam is a Comp XE268H and rockers are 1.6 ratio. I am suspecting I'm reaching the point of diminishing returns on these heads and a nice set of aluminum heads sounds great, if I can swing it...
What does everyone think? Is it worth re-using the 906 heads and get a bigger cam or am I at it's upper limit for flow already? Cam is a Comp XE268H and rockers are 1.6 ratio. I am suspecting I'm reaching the point of diminishing returns on these heads and a nice set of aluminum heads sounds great, if I can swing it...
What's the et goal and what's the budget.
BSB67
Well-Known Member
What brand of rocker?
Generally, for most rockers, the magical one or two threads showing is recommended by "people". As someone mentioned, how the ball/cup is oiled matters as well. Generally, you want as little adjuster hanging out below the rocker body while maintaining good oiling. The angular load on the adjuster becomes very large a full lift. The more it is haning out the bottom of the lifter, the worse it gets.
The one to two thread general rule seems to be recommended without consideration of the type/style of adjuster. See the link.
https://blog.trendperform.com/introducing-trend-performances-new-rocker-arm-adjusters
Some have the ball more extended from the last thread. The one to two thread recommendation, which has been around for about 50 years, was usually for the short adjusters found on the rockers available at the time.
So in your case, it looks like you have nearly 4 threads showing and a long adjuster. I'm guessing that your pushrod cup is nearly 1/4" away from the rocker body. I would shoot for 0.060 -0.090" Your oiling is directed right at the top of the underside of the rocker.
If you were not replacing your pushrods, and just using a hydraulic cam, I would not recommend replacing them. But considering that you are replacing them, I suggest getting loner ones.
7t500
Well-Known Member
No ET goal, just looking for extremely fun street driving that can keep up with the Jones. Budget isn't set in stone yet and I have some spare parts I can sell to get some more budget if needed. I'm just trying to figure out what I should expect for budget and assess the feasibility.
7t500
Well-Known Member
The rockers are the Mancini Racing aluminum HS rockers. I really love the qealth of knowledge here and appreciate everyone taking the time to help educate us not in the know! I will look more into the oiling aspect and see what I find
Thanks!
BSB67
Well-Known Member
I think you can simply look at the rocker and see how the pushrod cup is oiled. It's pretty clear in one of the pictures.
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BSB67
Well-Known Member
"...heads/cam/converter/3.23 gears..."
There's $3,000 plus. You would benefit from all of those things. Do you have $3,000?
We don't know what power you are making now, but I'll say that you have not reached the limit of the 906 heads with that cam. You're already buying pushrods. I would probably look to a cam swap for more power. More power with a cam swap will be easy, BUT, you might lose some low end power. Is that okay? I was recently reminded again that some people confuse power with driving "feel" (i.e. ability to spin tires).
Balancing what you have, and what I think you want, maybe try one of the following two cams:
1) Comp XS268S, or
2) Comp XS274s ground with a 112 LSA.
These are solid lifter cams. You'll need to check if your valve springs will need to be replaced. They will make noise, but maybe not too much more than what you have now.
The first cam should have similar characteristics as your current cam down low, but should pull a little harder up top.
The second cam will be a little softer down low but still fine with your gear and converter. It will make noticably more power mid rpm and up.
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threewood
Well-Known Member
I agree on longer pushrods. Been there, done that. I had adjusters out 2 full threads and burned up a few cups. I was using Smith Bros pushrods too.
Switched to Hughes rockers and set up the adjusters to have clearance on the rocker at full lift and have the squirter hit the ball/cup. Here is a picture of my current setup. Zero issues.
Switched to Hughes rockers and set up the adjusters to have clearance on the rocker at full lift and have the squirter hit the ball/cup. Here is a picture of my current setup. Zero issues.
I agree the adjuster looks to be out to far.... But at the same time if the pushrod is to long the cup hits the bottom of the rocker instead of only riding on the ball, and that situation results in similar damage.... People tend to think rockers are the simple part of building an engine... It's not, there's allot to pay attention to, if you don't it will bite you..
wagonman
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FWIW I saw a video on Uncle Tonys about lifter failure. Remanufactured lifters. Probably dont apply to your issue but Holy Crap whats next.
7t500
Well-Known Member
Well, time to revive this one. After a few months of research, waiting for available heads, etc.; I am finally moving forward. The plan is:
-TrickFlow 240s
-Comp XE285HL-10
-Comp Pro Magnum lifters
-MRE 1.6 roller rockers
I have verified Cam/crank timing and am getting to the point of measuring for pushrods. I am not making my own and will be ordering a set (Smith Bros, Trend, Manton are the current contenders unless i happen to fall on an off-the-shelf length. I have everything mocked up currently and wanted to see what everyone thought of my rocker adjusters.
-TrickFlow 240s
-Comp XE285HL-10
-Comp Pro Magnum lifters
-MRE 1.6 roller rockers
I have verified Cam/crank timing and am getting to the point of measuring for pushrods. I am not making my own and will be ordering a set (Smith Bros, Trend, Manton are the current contenders unless i happen to fall on an off-the-shelf length. I have everything mocked up currently and wanted to see what everyone thought of my rocker adjusters.
Wietse
Well-Known Member
Thats a long adjuster being used with a press fit push rod.
Imagen the side load when that swings upwards.
Wietse
Well-Known Member
You might want to extend that adjuster 3-4 / 1 turn as this is close..
Check again with 1 full thread below the rocker arm.
I can highly recommend Smith Bro's their product, i got a set from them also.
Check again with 1 full thread below the rocker arm.
I can highly recommend Smith Bro's their product, i got a set from them also.
7t500
Well-Known Member
I bet that aide load is why I broke one in the first place. I'm trying to get it right this time around.
I appreciate the feedback and was wondering if it needed to be a bit longer but I'm conflicted and stuck between the different recommendations of having it as short as possible, best oiling position, and the general 1-2 threads rule... I'll try to get a better picture showing the oiling hole as that may make a difference based on the research I have done.
7t500
Well-Known Member
Here is a shot showing the oiling hole
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