Are These Factory Rocker Arms on my 1973 340ci ?

[toolmanmike]

Stock 273's have a adjuster and no lock nut. Those are aftermarket or stockers that have been modified. Tap the engine over to the base circle and slide a feeler gauge between the valve stem and the rocker pad. If you have .012-.020 clearance it''s a solid. Hydraulic won't have clearance but you will have to back the adjuster off a half to a full turn to get to Zero clearance. Here's stock 273 rockers.

 

[66Satellite47]

Stock 273's have a adjuster and no lock nut. Those are aftermarket or stocker that have been modified. Iap the engine over to the base circle and slide a feeler gauge between the valve stem and the rocker pad. If you have .012-.020 clearance it''s a solid. Hydraulic won't have clearance but you will have to back the adjuster off a half to a full turn to get to Zero clearance. Here's stock 273 rockers.

View attachment 929690

Thanks Mike I did not recall that those 273 rockers did not have lock nuts. My BB Isky stuff did. But now thinking of my buddy's 273 rockers, bet they didn't.

 

[Moparfiend]

Good timing guys thanks for keeping up with me on this. I was out actually checking the lash and it sure looks like I must have solid lifters as the lash is 0.017 in on #2 and #6 intake.

 

[Moparfiend]

The lifter marks on one side facing the rear of the car is “380” and the side facing the front have different alpha numerics but typically look like “W7” “IV24” etc.

 

[33 IMP]

I dont mean to derail the thread, but.... do big block adjustable rockers interchange with small blocks? The reason i ask, the rockers in post #1 look exactly like the big block rockers that came on my maxwedge. Screwslot adjuster with a locknut. I am away from my engine at the moment or i would get a pic. Memory says i've got a lube hole in the top too.

 

[Moparfiend]

Just a few more:

 

[toolmanmike]

Looks like you have a mix match but that's ok. The non lock nut adjuster rockers are a interference fit to keep them in adjustment. Those can be changed to lock nut types but they have to be spot faced so the adjusting nut is flat against the rocker.

 

[Moparfiend]

One more

 

[Moparfiend]

Looks like you have a mix match but that's ok. The non lock nut adjuster rockers are a interference fit to keep them in adjustment. Those can be changed to lock nut types but they have to be spot faced so the adjusting nut is flat against the rocker.

Looks like all the intake valves have the non lock nut adjust screw. Wonder why? If they are interference fit how are they adjusted?

 

[toolmanmike]

One more

View attachment 929725

Those are aftermarket pushrods.

Looks like all the intake valves have the non lock nut adjust screw. Wonder why? If they are interference fit how are they adjusted?

Just turn the adjuster screw. They turn fairly hard. You can still buy adjusters and that can help with loose ones. You can also lay the rockers sideways on a vice anvil with the adjuster removed and hit the adjuster end with a hammer to distort the adjuster hole. hat will tighten them up as well.

 

[Moparfiend]

So let me see if I am understanding this correctly.

1. These are aftermarket valve rockers and they are stronger than the stamped cupped stock ones.
2. Hydraulic lifter set up will have 0 lash and what ever tightness past that (like 90 degrees etc) which means that at any point in the valve position I should not have a gap.
3. I measured a 0.016 gap on two valves. This indicates that either the vales are loose or I have a solid lifter which is typically gapped in that range ie .010 to .020 range.

Right?

 

[wyrmrider]

Big block do not interchange
neither do Ford 1.75 or Olds 1.8
had customers try and make these work
that's early Olds Gotha arms

 

[66Satellite47]

I dont mean to derail the thread, but.... do big block adjustable rockers interchange with small blocks? The reason i ask, the rockers in post #1 look exactly like the big block rockers that came on my maxwedge. Screwslot adjuster with a locknut. I am away from my engine at the moment or i would get a pic. Memory says i've got a lube hole in the top too.

No, SB & BB rockers do not interchange.

 

[66Satellite47]

So let me see if I am understanding this correctly.

1. These are aftermarket valve rockers and they are stronger than the stamped cupped stock ones.
2. Hydraulic lifter set up will have 0 lash and what ever tightness past that (like 90 degrees etc) which means that at any point in the valve position I should not have a gap.
3. I measured a 0.016 gap on two valves. This indicates that either the vales are loose or I have a solid lifter which is typically gapped in that range ie .010 to .020 range.

Right?

The intake rockers appear to be the OEM 273 rockers, the exhaust appear to be either aftermarket (brand?) or OEM. Check both intake & exhaust to see if the area under the lock nut is machined. All those rockers are stronger IMHO than the stock stamped hydraulic rockers. Having lash sure indicates a solid lifter cam. If it is a hydraulic, you have serious problems. Lash recommendations vary widely from one cam grind to another. Would be nice to know what the cam actually is. Using the interference fit adjusters, I'd sure check the lash fairly frequently. Others on this site will have much more knowledge than me on the SB rockers and the need for lash checking.