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Roller Rockers

You really do. The thermostat housing will contact the valve cover without it.
 
This sorta shows it.

Trust me its necessary.

2012-01-21_17-26-53_33.jpg
 
More stable valve train (e.g. you get the advertised ratio, and a stronger rocker with less flex), setting preload is precise and a breeze, reduced heat going to the oil, and possibly a little HP. They are rebuild-able and Harland Sharp's support is excellent. I don't have roller lifters as you would need a roller cam setup for it and the only one available is 505's over priced cast cam kit. You may need longer push rods that stock though.
 
I'm not the engine builder on our team - but I can probably at least partially field this question.

We used them to get adjustable rockers. We are running Comp Cam's 'Pro Magnum' lifters which have less compression in them - so we can run much higher RPM's without getting slop in the valvetrain. IIRC they only pump up about .005 - no way you can run them without some manner of adjustable rocker. As it was, we ended up running .050 shorter push rods in a couple of holes to get things adjusted right.

We don't have a tach in the KOH car, but comparing our engine to competitors who do run a tach, we have to be pushing about 7,500 RPM's on the high end. Who knows, maybe higher.

Also, the generate less friction, you have more control over valve train geometry and rocker ratio (you can get them in multiple ratios)..and they make more sexy.

If you wanted to get more info, give Russ Pottenger a call at Bishop-Buehl racing engines.

Bishop-Buehl Racing Engines
West Covina, California 91790
Work (626) 967-1000
Fax (626) 967-7836
Email RussBnBracing at yahoo.com
 
Yes.. it too bad all that sexy in the engine is hidden.
5.jpg


In Cal's case, they most likely adjusted the valves with the engine off. In your application, did you adjust them with the engine running?

Back when I was a marine mechanic, hydraulic lifters were adjusted with the engine running (most of the time) and solid lifters with the engine off. We used to use the Chevy small block or big block as a base and add after market parts and go do amature racing on week ends.
 
You adjust them to .002 ish beyond 0 lash, so I don't think you could physically manage it with the engine running.
 
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I am not running the Pro Magnum lifters, so the preload is as factory. I set them with the engine off. It would be a little bit difficult to set them with the engine running as the adjuster is over the pushrod, not over the pivot like most.
 
Just an additional FYI... If you are looking to improve valve train performance, consider using at least a double wound valve spring. They replace the single wound with a pair of thinner diameter springs. Upshot is that you can run higher lift cams without the worry of binding the valve springs. Also, reduces the likelyhood of both valve bounce and float. If you are really after it, Titanium spring keepers and push rods will reduce the valve train weight making control easier.
 
I am not running the Pro Magnum lifters, so the preload is as factory. I set them with the engine off. It would be a little bit difficult to set them with the engine running as the adjuster is over the pushrod, not over the pivot like most.


I have done it both ways. With the engine running, I use a box wrench and an allen wrench. Simply loosen the adjusting screw until the valves tap a bit, tighten the screw until the tapping go away then 1/4 to 1/2 turn to move the valves in the lifter to the center of its travel before tightening the lock nut. With the engine off one would rotate the enging to a set point as indicated on the timing marks and set the appropriate valves to 0 lash then 1/4 turn for the hydraulic lifters or set the solid lifters to the correct lash using a feeler guage.

It is good to know that the valves are adjustable using the rocker arms that are shown in the pictures. In addition to the benifits listed in the previous threads are there any noticeable performance gains from using rooler rockers in the un-modified 4.0L?
 
If you are really after it, Titanium spring keepers and push rods will reduce the valve train weight making control easier.
Titanium pushrods are not recommended. Titanium is springy and does not have the properties needed in a push rod. Push rod stiffness is far more important than being light weight. The weight on the cam side of the rocker is also much less important than the weight on the valve side of the rocker. Titanium retainers are beneficial for weight reduction, though.
 
With the engine off one would rotate the enging to a set point as indicated on the timing marks and set the appropriate valves to 0 lash then 1/4 turn for the hydraulic lifters or set the solid lifters to the correct lash using a feeler guage.
What timing marks? You just rotate the engine until the lifter is on the heel of the cam lobe. Which is usually TDC of the compression stroke. Or you can rotate until the exhaust lifter starts to move up, adjust the intake preload. Then rotate the engine until the intake opens and then until it almost all the way back down and set the exhaust preload.
 
What timing marks? You just rotate the engine until the lifter is on the heel of the cam lobe. Which is usually TDC of the compression stroke. Or you can rotate until the exhaust lifter starts to move up, adjust the intake preload. Then rotate the engine until the intake opens and then until it almost all the way back down and set the exhaust preload.

Yea. I know that one. It takes a bit more time since you could only set one cylinder at a time. The procedure I used enabled you to set half of the valves at a time. Rotate the engine and set the other half. For myself or my friends I set one cylinder at a time. When charging a customer $50+ per hour and at the same time want to complete the job in the alloted time per work shop manual, speed is every thing.
 
Are the rocker shafts all in line? Can a single shaft mounted system be made instead of stud mounted roller rockers? Are there any other rockers that will work? ie SBC, BBC, Mopar, etc?
 
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