273 adjustable rockers need refurbish.

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MOA

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They came off a commando, no banana groves, shafts are galled, rockers have some galling on a few.

Need new shafts and bushings installed, is it worth it? They are going on a 318. KB 167 pistons I'm told it has 9.46 to 1 compression, I have a bit invested in this, I am lookin for performance.
 
If the shafts are just grooved not not worn, polish them. Run a none through the rockers to knock off the high spots and run them. Unless you have 240 on the seat it won't care.

If you want them bushed, IIRC the place is called Rocker Arm Specialties. They can do it.
 
Nothing special about the Rocker shafts, new would be better.
 
You need the banana grooves with the Commando adjustable rockers. That's how they oil...not having the grooves is probably why they're galled.
 
I was quoted 350 for the job. That's with Allen adjustable with nut and banana grove shafts.
 
My 65 273s were not grooved. I thought the >65 273's and 340 T/A's got the groove as well as the aftermarket? I agree, buy them used here ready to go.
 
I probably got 5 sets of crane rockers with shafts...none of them have grooves in them...TA rockers came with grooves...W2 shafts have grooves...my 2 sets of crane ductile iron rockers have no grooves....alot of non groove shafts out there running adjustable rockers
 
Do you have non adjustable rockers running on the motor now? And you want to put these on to add performance?
MOA said:
They came off a commando, no banana groves, shafts are galled, rockers have some galling on a few.

Need new shafts and bushings installed, is it worth it? They are going on a 318. KB 167 pistons I'm told it has 9.46 to 1 compression, I have a bit invested in this, I am lookin for performance.
Click to expand...
 
70aarcuda said:
I probably got 5 sets of crane rockers with shafts...none of them have grooves in them...TA rockers came with grooves...W2 shafts have grooves...my 2 sets of crane ductile iron rockers have no grooves....alot of non groove shafts out there running adjustable rockers
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Yes...maybe aftermarkets don't need groves. Every set of factory iron adjustables I've seen have had the grooves.
 
350, and I do the install. I want the adjustable so I don't have to mess around getting the lifter preload set correctly. I want full lift and full duration on every valve.

This is a fresh rebuilt 318,not running yet. All drive train is newly rebuilt.

I was going to just freshen up the engine but that didn't work out. When doing so, I ran into the problem of lack of preload on the lifters,all of them needing different length pushrods,what a pain in the ***.

Getting a set of used rockers is what I already have, buying another set doesn't make much sense unless they are in very good condition.

If I could find some that are in good condition,verified,I would likely just buy them and be done with this part.
 
Do you have a picture othe worn-out ones? Both the shaft and rockers are beyond scratches, they're groved up?


MOA said:
350, and I do the install. I want the adjustable so I don't have to mess around getting the lifter preload set correctly. I want full lift and full duration on every valve.

This is a fresh rebuilt 318,not running yet. All drive train is newly rebuilt.

I was going to just freshen up the engine but that didn't work out. When doing so, I ran into the problem of lack of preload on the lifters,all of them needing different length pushrods,what a pain in the ***.

Getting a set of used rockers is what I already have, buying another set doesn't make much sense unless they are in very good condition.

If I could find some that are in good condition,verified,I would likely just buy them and be done with this part.
Click to expand...
 
I have a set for sale on this forum, but I'd like to confirm yours are dead before I push that idea. Besides I'm a little to proud of mine to be pushing.
how far apart are the pushrod lengths? New build?
 
Okay I need to wrap my head around this a little better so you're saying brand new lifters that have a need for all different pushrods? And the cure for this is adjustable rockers?
 
$350 MIGHT be a little on the high end. Stock factory with banana grooves are usually $150-200.
Now if they have been bushed and machined for locknut $350 isnt that far outta line.
MOA said:
I was quoted 350 for the job. That's with Allen adjustable with nut and banana grove shafts.
Click to expand...
 
MOA said:
350, and I do the install. I want the adjustable so I don't have to mess around getting the lifter preload set correctly. I want full lift and full duration on every valve.
Click to expand...
This sounds like you have a hydraulic lifter cam. If that is the case, then different preload values do not effect lift and duration. The one thing that a small preload does for you is limit how much the valves can float IF they ever float when over-revved. And that may be a good thing to achieve, but, again, it is not effecting lift and duration to have different lifter preloads.

Can you give us a bit more info on the total variation in preload that you found? Or were there some that had no preload at all? Was this with stock stamped rockers? Out of curiousity, were the heads rebuilt, or just the valves lapped, or ???

FWIW, some good used 273 rockers sounds like a better deal. You can get the Crane adjusters with locknuts for around $45-50 for a full set.
 
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MOA said:
I was quoted 350 for the job. That's with Allen adjustable with nut and banana grove shafts.
Click to expand...

These adjusting studs and nuts are great replacements... We used them on a 340 that we built last year with stock 273 adjustable rocker arms...

I would spot face the surface of the rocker arm flat so the adjusting nut will bottom out properly... You can do it with a bench grinder at home if you're careful...

https://www.summitracing.com/parts/..._-crane-cams&gclid=CPC0zrX8lNICFYQvgQoduD0N4g
 
If the new engine was completely rebuilt I would just run a light hone or some emery cloth thru the rockers, put them on new shafts, and run them. No need for grooves on a milder build that's fresh. Varying pushrod lengths are normal if the block was not blueprinted and the valve job was not done well. But givent he range of preload on most stock type lifters is generaous, get a length that will give adequate minimum preload on the shortest one, and that should be fine on any of the others.
 
j par said:
Okay I need to wrap my head around this a little better so you're saying brand new lifters that have a need for all different pushrods? And the cure for this is adjustable rockers?
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Yes, because the non adjustable rockers all have different amounts of wear even with new pushrods. At least that's my theory. Assuming the heads were done right.heads were done by a shop that has been in biz a long time.

Cam is new,lifters are new,pushrods new.
 
On my teener dressed as a 273, when I installed the crane adjusters, one hit the baffle in the valve cover. Had to massage the sheet metal some to keep from hitting. Commando Valve covers.
 
I can't post pictures here or I would.

I had at least threelifters that had less than zero pre load. I checked across the tops of the valves with a straight edge and they were not even, I took them back for them to correct this problem.

.010 shaved off the heads at that time. I ported the heads myself, most of the work was on the exhaust side,some bowl work. Going into Doug's headers.

.040 over kb167 piston, block machined,pistons are between .004 and .006 down in t the hole. 028 head gasket. Heads cc'd out at 65cc

I was told that equals 9.46 compression.
 
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Mopar Tim said:
On my teener dressed as a 273, when I installed the crane adjusters, one hit the baffle in the valve cover. Had to massage the sheet metal some to keep from hitting. Commando Valve covers.
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I kind of expected I may have to do the same as you.

I have a set of covers that are wrinkle black with chrome cooling fins that have a notch for the plug wires to sit in, have no idea what they are but the look pretty cool and have the wire looms built on.
 
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