273 adjustable rockers need refurbish.

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Lash caps? No, I don't know what they are.
 
If you had solid lifters, you'd be writing about not having enough valve lash for the pushrods you're using. Any lash is hydraulically corrected with a hydraulic cam, but you're seeing wild preload swings from lifter to lifter. Lash caps sit on top of the valve stem, under the rocker and take up the slack from the mismatched valve tip heights.

This isn't supposed to be gospel on how to build an engine but it would work, like other ideas. At least youd have consistent rocker arm geometry (as consistent as 1960's get).

I fucked up before and bought pushrods before taking measurements and it sucks. Wasted money. But I learned a lot. I always measure with an adjustable pushrod, measure the max lift the valve will obtain using the rocker adjuster and use the adj rod to take up all slack, then witness the sweep pattern over the valve. Then measure and buy that pushrod.

Sucks that the valves aren't at a consistent height and this is the root problem. Either get the heads worked, use lash caps to correct the heights, or use the adjusters and pushrods you have. I'd say there is a great chance you'll have to buy new pushrods anyways.

Unfortunately, pushrods should be the last part you buy because you need the proper measurements first instead of trying on making xyz pushrod fit.
 
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I checked across the tops of the valves with a machinist straight edge and feeler gauges, the largest gap is .009, a couple at .006.
I'm pretty sure I will be told that is within spec.
 
I checked across the tops of the valves with a machinist straight edge and feeler gauges, the largest gap is .009, a couple at .006.
I'm pretty sure I will be told that is within spec.


If the stem heights are that close, either the rockers are off (unlikely) or the base circles are different. I've seen that many times, especially on reground cams.

The 273 rockers you have are fine. Just polish the high spots out of the bore and run them. Either way, you need shafts, right?

I can say that since 1980, I've run hydraulic rockers twice. Once on my engine, until I broke one and lost $250.00. The other was 1999. Brand new rockers. Broke on the dyno. I know there are many in use. It just isn't worth it.

Ok three times. The car I now own came with hydraulic rocker. Those were changed out very quickly.

So 3 times.
 
Stock stamped rockers with new shafts,measure pushrod length and order custom length pushrods seem to be the best choice here.

Abandon the adjustable rocker idea.

I don't have money to waste on this project and I've already wasted too much on mistakes.

Thanks for all of the help from everyone.
 
To be clear, and I don't think I was. The initial install was with the old rockers and shafts. That experience pushed me toward adjustable rockers.

I have used stock length cup and ball pushrods, measured 7.500
 
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Then you have other issues. .009 difference in valve heights doesn't amplify into a .080 difference in preload problem. The preload difference is coming from somewhere.

-Your pushrods are bent
-Your block deck height is inconsistent by checking 1,2,7,8
-the heads weren't shaved consistently
-measurements are inaccurate

When you're checking all this, the head is torqued down with the gasket to at least 50% torque? Is there any way that the dowels in the block deck are damaged or mushroomed, preventing the head from sitting down flush on the block with less than 100% torque?
 
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At this power level and lift you think he should "call someone" or just run some stock stamps ? Personally, I think this is getting over thought...

I disagree. I believe that at his power level he can show great benefit from a good, consistent ratio set of adjustable rockers. He can adjust the lifter preload dead on, instead of relying on whether or not the stamped rockers are consistent. These are the kind of details that can add up to make missed power, and at the mild to moderate power levels, that can add up quickly.
 
To be clear, and I don't think I was. The initial install was with the old rockers and shafts. That experience pushed me toward adjustable rockers.

I have used stock length cup and ball pushrods, measured 7.500

If you used that length for a hydraulic cam and 273 rocker arms, they are most likely too long...

We used crane adjustable studs on the rocker arms and ended up with 7.090" long push rods from cup to ball...
 
with ball and cup pushrods.,.,,,7.50 are for adjustable rockers with solid lifters.....7.33 are for adjustable rockers with hydraulic cams...
 
I don't know what to do at this point. I bought new stamped rocker arms and rocker arm shafts. Preload is still all over the place, I'm told this is normal for dodge. Doesn't seem normal to me.

Everything is new or rebuilt, refurbishing the adjustable arms is expensive and I would need new pushrods.

Or, take it to the machine shop that built the engine and let them deal with it, which would probably be cheaper in the end. Not better, cheaper. I'm already out of money.
 
I don't know what to do at this point. I bought new stamped rocker arms and rocker arm shafts. Preload is still all over the place, I'm told this is normal for dodge. Doesn't seem normal to me.

Everything is new or rebuilt, refurbishing the adjustable arms is expensive and I would need new pushrods.

Or, take it to the machine shop that built the engine and let them deal with it, which would probably be cheaper in the end. Not better, cheaper. I'm already out of money.
I'll make a suggestion: Take the following numbers and put them in a table per cylinder number:
- Push rod length for each individual pushrod
- Valve stem variation with the straight edge
- Preload measured
You might see a pattern emerge that will help point to any issue.

BTW I would indeed expect variation with stamped rockers; there is simply going to be some variation in parts made that way. How much variation do you have now?

And the only issue that you will have with variation, as long as there is SOME preload in each lifter, is that some lifters can pump up and float the valves more than others if you reach the RPM's where the valves float. What cam do you have? That will influence how prone it is to floating valves, steeper ramps would genenrally tend to float valves more readily.
 
ex268h-10 with high energy lifters.

After giving it some thought, I'm going to rebuild the adjustable rocker arms.

I just can't stand it not being right! I've spent a lot of time matching parts for a complete package, I'm not going to half *** the last piece of the build.
 
Where is a good place to get shim washers?
 
I think 340's had grooves. 273's no.

the only 340s from the factory that had adjustable rocker arms were the 6 pac motors...and yes..those shafts have grooves.....otherwise all 340s had nonadjustable rockers and those have no grooves.
 
At this power level and lift you think he should "call someone" or just run some stock stamps ? Personally, I think this is getting over thought...

It's sorta like a Dana 60. Do you want an 8.250 that "might" break, or do you want a Dana that will "NEVER" break? Those ductile rockers properly prepared will never break at his power range and they are reasonable prepared right. Do it once. Do it right.
 
It's sorta like a Dana 60. Do you want an 8.250 that "might" break, or do you want a Dana that will "NEVER" break? Those ductile rockers properly prepared will never break at his power range and they are reasonable prepared right. Do it once. Do it right.
You're seriously quoting me from something I said three months ago! This is a joke right? I have to go read through this whole entire thread to find out where it's at and what I said three months ago? Forget it! This is somebody else's problem probably! That they fixed 2 months ago likely.
 
I'm not a "speed reader" either. In first grade I was taught to read one word at a time. I guess competent speed readers capture phrases instead of just words. I'm too old at this point to speed things up.
 
You're seriously quoting me from something I said three months ago! This is a joke right? I have to go read through this whole entire thread to find out where it's at and what I said three months ago? Forget it! This is somebody else's problem probably! That they fixed 2 months ago likely.

Yeah. Steve liked a post and then I saw yours. Stop bitchin. You caint have it both ways. First you said I was ignoring you. Now you're bitchin about me respondin. I'm gonna call you Hillary.
 
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