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Beat up Mechanical Rockers


mstieg
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So it turns out that the mechanical rockers I got are chipped and not usable in their current condition.

 

Where can I get new adjusting screws for them? (or do I need a replacement set??)

 

http://www.26liter.us/gallery/albums/userpics/10168/normal_mech_rockers.JPG

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So it turns out that the mechanical rockers I got are chipped and not usable in their current condition.

 

Where can I get new adjusting screws for them? (or do I need a replacement set??)

 

http://www.26liter.us/gallery/albums/userpics/10168/normal_mech_rockers.JPG

 

 

Look into getting some of these

 

http://69.0.158.19/live/W01331633604OEA.JPG

 

A bit pricey but worth the money and keep your valves and rocker arms from smashing.

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I can recondition the rockers entirely to an upgrade condition from OEM. Better for hi-RPM and heavier valvesprings. The shafts get upgraded too, and the rockers machined to fit and bushed if needed, for a smooth as glass operation so to speak. Any performance mechanical set-up could really use this upgrade.

Price is $175 a set , plus cores, shipped.

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I can recondition the rockers entirely to an upgrade condition from OEM. Better for hi-RPM and heavier valvesprings. The shafts get upgraded too, and the rockers machined to fit and bushed if needed, for a smooth as glass operation so to speak. Any performance mechanical set-up could really use this upgrade.

Price is $175 a set , plus cores, shipped.

 

 

mmmmm interesting... might have to get back to you on that.

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My machinists who do this work are old pros who only work on rockers and rocker shaft assemblies. They know what their work is worth, and charge accordingly.

1. Professionally clean all parts to be free of oil varnish, etc... This includes all oiling holes checked to be free of varnish and completely open.

2. Recondition adjustment screw tips, and reharden. Some adjustment screws are beyond repair. The ones pictured in this thread are probably not useable, but that is determined professionally upon seeing what it will take to clean them up.

3. Professionally cut off the jet-valve arms on intake rockers.

4. Deburr/chamfer any sharp edges and replate the shafts. The plating process is for hardening, and to make them slicker.

5. Machine fit the rockers to the shafts. Sometimes this requires bushings, but both bushed and non-bushed operate the same and have the same longevity.

6. Lift the slipper pad arch for a new surface and better geometry fit with the cam lobe.

7. Other standard checks and work is done to ensure a trouble free set-up within the rocker and shaft assemblies.

Special requests? Let me know, and I'll see if we can do it.

The upgrade reconditioning is race proven on 160+ Lb seat pressure valvesprings, 9,000+RPM engines by Corky Bell, among many others.

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Thanks Tim.

 

I'm getting new mech. adjusting screws from Dad to replace that crap you see above (only $1.50 each). It does seem that these rockers could use a bit of work also.

 

Now, I have the stock hydrolic shafts currently. Would your $175 service include a swap to the mech. shafts without the extra oil hole? Did Corky run 9k on the G54b?

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I'd just drill a tiny hole in the rocker arm and spend the $$ to get elephant feet and be done with those dumb screws they will always require adjusting and replacement and you'll need to keep those hydraulic shafts but until you use them you won't understand, their clearance is just barely enough for oil clearance, no noise at all

 

http://www.b2600turbo.com/images/IM000576a.JPG

 

http://www.b2600turbo.com/images/IM000733.JPG

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Thanks Indy,

 

I might need more explaination. The hole will basically use the hydrolic shafts' oil supply to lube the rockers?

 

Those elephant screws don't need adjusting while the OEM replacement ones do? What's the diff? Please clarify more. Thanks.

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Thanks Indy,

 

I might need more explaination. The hole will basically use the hydrolic shafts' oil supply to lube the rockers?

 

Those elephant screws don't need adjusting while the OEM replacement ones do? What's the diff? Please clarify more. Thanks.

 

Things to consider.... How much can you buy a new set of rockers for if you can get them for $12 apiece why rebuild? In general they hold up very well and for a long time on most builds.

 

There are two actions that occur at the adjuster tip.

 

One is the tip presses the valve downwards.

 

Two the tip moves in an arc as it presses the valve down (since its fixed to the rocker arm that pivots in an arc on the rocker shaft). The valve stem does not move in an arc so there is lateral movment between the adjuster and the tip of the valve.

 

If the tip has a radius ground into it the side laoding of the valve in minimized (it just kind of rolls over the valve tip). The same goes for using a roller tip to push a valve down and in fact that is why they were invented.

 

If you put a wide based "foot" on the tip the unit loading goes down and you get less wear at the push point, but the tip does not roll over the valve stem as it swings in an arc (instead it has to slide), that increases the side load on the valve stem. Basicly you make one problem better but possibly create a new one and shorten the life of the valve guide.

 

The radius ground into the adjusters tip is important. The guys at the factory did think about this. :character0285:

 

To improve the performance of the rocker shaft bushing your have a few choices.

 

1: Use a better bushing material in the rocker arm

 

2: Harden the rocker shafts (from the factory they are wimpy soft).

 

3: Do both

 

4: get hardened shafts and needle bearings for the rocker arms. To fit the needle bearings you may need to fab up a set of rockers from scratch.

 

The upside is the parts holdup very well stock. Bang for the buck is to send the shafts out for nitriding, second is to use bronze bushings in the rockers. My motor? Its harden the shafts first.

 

Best choice? IMHO Dad's fresh set of adjusters.

 

Curious about your motor, how much cam , spring pressure and RPM range you are running?

 

I hope this made sense,

 

Kevin C

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new screws are not gona solve your problem,, they were worn because of valve float,,you need new springs

 

Yes they will, since those rockers sure didn't come off of my engine. I bought them from another member over a year ago, and they've been sitting. =)

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OEM rockers leave a lot to be desired for a performance application. They gall on the shafts especially with HD or heavier springs. The pads are too low and need lifted.

If you drill the rocker, be sure to chamfer the inner hole or it will gall on the shaft. Manufacturing machine work is more the problem than oiling. The rockers don't properly fit the shafts, and the shaft to rocker mating surfaces are not smooth enough, etc... Too many imperfections in manufacturing. You want them smooth as glass, which I have never seen outside of the upgraded sets.

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OEM rockers leave a lot to be desired for a performance application. They gall on the shafts especially with HD or heavier springs. The pads are too low and need lifted.

If you drill the rocker, be sure to chamfer the inner hole or it will gall on the shaft. Manufacturing machine work is more the problem than oiling. The rockers don't properly fit the shafts, and the shaft to rocker mating surfaces are not smooth enough, etc... Too many imperfections in manufacturing. You want them smooth as glass, which I have never seen outside of the upgraded sets.

 

Curious how you lift brazed on pads? Perhaps you are refering to off-setting the bushing in the arm? The factor thats normally off is the base circle of the cam was ground too small.

 

A very simple solution to the bushing problem that works better and costs less: Run a hardened rocker shaft and the bushing issue goes away, the softer rocker beds into the shaft without scoring even using higher spring pressures ( the same reason the factory went to a nitrided crank), this setup will work signifigantly better than bushed rockers on a soft rocker shaft. Even a bushed set of rockers will work a lot better with hardened rocker shafts!

 

If you want to try this setup I can point you to a company that can nitride the rocker shafts.

 

Kevin

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Yes, the shafts do get hardened. It is a type of chroming that also makes them slicker. I'm not the expert on the process. I just know it is proven, and done by professionals who only work on rocker assemblies. Many for race applications. They've been doing it for many many years, and don't like to tell all when it comes to their process. I don't like asking either. As long as it works, I wouldn't think of going anywhere else. They treat me pretty good.

 

Yes, the issue is the smaller base of a performance cam, and a worn slipper pad on used rockers. New rockers still don't get near the smoothness on the shaft as the refurbished/upgraded ones. I figure why get new ones if I need to have them worked too.

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Curious about your motor, how much cam , spring pressure and RPM range you are running?

 

I hope this made sense,

 

Kevin C

 

Sorry, I missed answering this before

 

- HD Schneider Springs

- TEP's street/strip performance cam (came with their head setup when I got the longblock 2nd hand)

- The cam is a .435 lift x 272 Intake and 274 Exhaust (according to them that is - don't have a caliper to measure myself) TEP recommended 10-12 deg. advance

 

Any tuning suggestions for this cam would be helpful. The engine is forged .20 over, no jet valves or Bal shafts, and will begin new life as MPI using the Hawk ECM along with a new Chad header and S256 turbo this weekend.

 

So it sounds like the screws will do it for now, and I should consider getting those shafts nitrided and the rockers re-manned later.

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Thanks Tim.

 

I'm getting new mech. adjusting screws from Dad to replace that crap you see above (only $1.50 each). It does seem that these rockers could use a bit of work also.

 

Now, I have the stock hydrolic shafts currently. Would your $175 service include a swap to the mech. shafts without the extra oil hole? Did Corky run 9k on the G54b?

 

I missed your post, sorry!

Yeah, the stock replacement screws will work very well. Another reason they start looking like the ones in your picture is because they never get readjusted and have too much lash. When periodic adjustments are made, the contact point on the screw moves around to not wear the same place all the time too.

They tell me the hydraulic shafts don't really help or hurt anything. I usually try to use mech shafts, but it really doesn't matter. Another gain from the rework is the proper oil pressure from the right clearance to get a better oil barrier between rocker and shaft.

They said it was a Toyota engine, but I forgot which one. Maybe a 22R? If I remember next time I talk to them, I'll ask.

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