[Billz428]

While setting my pushrod length and checking my wear pattern, I see that my rocker stud has only .257 of the threads left.
Is this enough ?

Valve Train

1. Crane Cam-283951- @.050 in-226 lift- .458 / ex- 234 lift .473
2. Crane Roller Rocker 1.65
3. Rhoades Lifters
4. Push rods Erson 9.680 #E917572
5. Crane Lash Caps 11/32 .060 thick
6. ARP poly locks
7.Edelbrock 72cc Heads -pushrod holes enlongated other wise stock.
8. Cometic head gasket .050

[Jack Gifford]

Without answering "is it enough", you're giving away a lot of strength. Rule-of-thumb for ultimate strength of hardened fine-thread fastener engagement is 1.5 times the diameter, which would be about .655" for those 7/16-20 studs. Granted, we don't always need the ultimate, but I would get longer studs, rather than trust just 1/4" of engagement.

Umm... looking at the picture again- you don't happen to have the trunnion upside-down in that rocker, do you?

[screamingchief]

That 9.680" pushrod length looks way too long to me.

That's a standard FT hydraulic cam,basically stock dimension lifters,the Eheads normally dont require substantially longer pushrods as SOP as I recall,and the lash caps should only add that .060" to the required length,add another .010" to .020" for the thick cometics...

So,unless those heads use some seriously long valves here,I'm betting money you ended up with too long of a pushrod in there somehow.

Not gonna even ask why the lash caps with a fairly mild flat tappet cam???

[Billz428]

The block was decked also, but I have no idea how much.
Lash cap seemed to be a good idea!

[screamingchief]

Originally Posted by billz428

The block was decked also, but I have no idea how much.
Lash cap seemed to be a good idea!

Sorry,but I just dont think your anywhere near where you would need that long of a pushrod...

Say the block was decked,in the most extreme case that's what,like .030" or so?

Besides,please do note that decking usually calls for a shorter pushrod as SOP,and not a longer pushrod,as you have shortened the distance between the lifter cup and the rocker arm cup,not increased it...

I would be real surprised to find the right length needed to be more than 9.300"-9.400" long at the most.

That means your pushrods would still be way too long here,.280" or more.

For the decimal impared members of the forum,that's still a 1/4" too long...

For pushrods,that is a LOT!!!

Stock FT pushrod length is 9.130" - 9.170" for most apps.

Longer valves,at most +.100" usually.
Lash caps + .060"
Thick cometics + .020"

That gets you to like 9.350" at best,and even that is a pretty good stretch here.

That does'nt even take into account the block decking reducing the length needed by that amount...

Seems real clear to me that your pushrods are too long here,JMO/FWIW.

That or there is some important bit of information is yet to be disclosed here...

If when checking the length on this engine,a hydraulic lifter was used,I highly suspect the lifter had bleed all the way down in the lifter body and was not at the correct preload height like it should have been.

[Billz428]

I shimmed up the lifter, to make it solid and keep extending my adjustable pushrod till I came to the wear pattern in my post above.
I was really surprised too.
I,m going to go through this some more later tommorow.
Thanx Chief and Jack.

[Billz428]

Well I went through it again today .
The factory rods will not even work.
9.4 the pattern is off, with no lashcap I had over .545 of stud threads for the polylock.

9.5 the pattern is better , no lashcap .525 of threads left.

9.68 with cap the pattern is centered,with a hardened washer stack under the stud, I had .445 of stud left for the poly lock.

The guide plate and washerstack are .290.
The stud is .745.

This leaves .455 going into the head.

Is there enough threads on both ends now to to the job

[screamingchief]

I shimmed up the lifter, to make it solid and keep extending my adjustable pushrod till I came to the wear pattern in my post above.

How exactly was this "shimming" done???

What lifter was it done too???

Your using the springs that came on the Eheads here,,,right???

Most folks do this with lightweight checking springs on the valves being tested...

There has to be something wrong with how this is being done here,the results are just too far out in left field IMO.

Explain as much as you possibly can for us in the future,this sorta deal the devil is in the details!

[screamingchief]

The factory rods will not even work.

How so???

I'll say this one last time then I give up.

I still believe that your waaayyy past the correct length here...

Even at 9.400" that is true IMHO.

And your chasing a pattern is just you chasing your tail here.

I've seen it happen more times than I care to mention here on this forum,and in person.

Something has gotta be going on here,but were at your mercy to figure it out.

As I've said earlier,nothing I can recall from the basic Eheads useage requires a significantly longer than stock pushrod when used with mostly stock hardware,only when something is changed on them does the required length of the pushrods change significantly as well.

Add a taller valve for a taller IH and yeah,sure then you need a longer pushrod.

But you imply these are outta the box "stock" Eheads,which has me at a loss to explain how you got to where you are now...

If you were using a roller cam,then I could see you needing a longer pushrod like that.

Or if you were using some solid cams & lifters that use a lower pushrod seat and a smaller base circle,those both often require longer pushrods.

Ask me,without those lash caps,and considering the roller rockers your using (crane energzier 1.65 by the looks of them) I would expect the needed length to be virtually the same as the stock pushrods which is around 9.130" to 9.170",and the block decking most likely would negate the thicker headgasket issue and cancel each other out pretty nicely,so at the most I would be trying this with would be a 9.200" long pushrod to begin with.

So you should see why I cant grasp how you came up with that 9.680" length to begin with?

So I ask...

Are there any extenuating circumstances that have'nt been mentioned yet that somehow demands a significantly longer pushrod???

I know a couple of the magazine build ups using box stock Eheads with flat tappet hydraulic cams and similar 1.65 roller rockers and those in fact used the stock length pushrod (9.130" appx.) in their builds and they were just fine...

Most of the Eheads I've personally been around were used along with roller cams,so those obviously required non-stock pushrods lengths,and even those were in the 9.250" to 9.350" range at the longest...

And those used longer than stock valves and taller spring installed heights as I recall.

You can get "good looking" patterns even when the pushrod length is way off,and occasionally even the opposite can happen,this is where the fine tuning of length comes in,but to begin with you gotta get the length into the ballpark,and I dont think your remotely close to that point yet.

I dunno,this is wearing me out...

Good luck with this.

[Billz428]

Thanx for your help and Interest Chief,

The lifter is a Rhoades - gutted and filled with a plastic rod cut just long enough to get the cup and retainer on with a tiny bit of play.

Crane Energizer 1.65 Rockers.

Factory Ehead springs.

.050 Cometic head gaskets.

The factory rods 9.130 are very close to the edge - the stud side- they almost run over!

The heads are snugged down by 4 head bolts - tight but not torqued.

I start off the base circle of the cam-rotate it twice- back to base cicrle -remove rocker arm- check pattern.

I have those lightweight springs also.

I,m stumped also, done a bunch of reading thru the archives and see rod lengths all over the board.

When I kept elongating the rod at .125 intervals and as the pattern got more favorable I stopped at 9 5/8- 9.625.

That is it in a nutshell.

[Jack Gifford]

Valve lengths?
Spring installed heights?

[Billz428]

I went back to basics then made one change Harland Sharp 1.65 .

With the 9.130 rod and the HS 1.65 rocker the pattern was great!

The Crane rocker body and those lashcaps got the rod length to growing.
the pattern was good but I had no stud threads left I was comfortable with.
I was really set on using the Crane rockers and it clouded my thinking,Hence the washer idea to make the stud appear longer but costing threads into the head.

The HS 1.65 have plenty of threads and way more clearance around the spring retainer.
The wear pattern is good to and I will not be using the lashcaps.

I can now finally get the long block finished .

A big Thanx to Screaming Chief & Pontaic Jack .

[screamingchief]

He PM'd me last night PJ,seems the rocker body and lash caps were interfering with the process,and thus why the stock length pushrod was'nt working for him,tried some harland sharp 1.65's and the deal all came together just fine.

That's like the second or third time I've seen a fella have a problem with those crane energizer 1.65 roller rockers and the geometry,and they always seem to chase a pattern and end up with much longer pushrods than are correct in the end.

I would hafta figure there is a situation occuring where the rocker arc comes and goes away with given pushrod lengths,get too far past a certain length and you end up with a pattern that looks "wrong" till you get to the next "working" arc for the next longer pushrod length,overshoot that point once or twice and you end up way past the "correct" pushrod length mislead by the fact that the pattern looks good,but then something else is at issue,like billz running out of threads on the studs,or another fella who was running out of rocker slot travel at full lift.

HTH.

P.S. Glad it all got straightened out!

[BILTIT]

Interesting, i never had any issues with my crane rockers but then again i am not running E-heads. 9.2 Pushrod length.