Re: Rockers for stock Eliminator 5.0 SBF
 

The subject of rocker arms in Ford blocks has been a debate for many years because different tech folks at NHRA have made different rulings throughout the years.

Many years ago, in the early 1990's, Jim Skelly approved the Crane conversion system shown earlier, for Cleveland and Windsor engines and there were many cars running the conversion.

Also, Mopar Big Blocks were allowed to run adjustable rockers because they were used on the Max Wedge and small blocks were allowed also because the 273 engine.

Some years ago when the rules were changed to allow guide plates and studs, there was not clarification for the use of the original configuration, therefore, many went ahead and followed the rule book and did so.

When the rule book was changed again a few years ago to allow roller rockers, then many racers started to ask NHRA about the configuration. Therefore, NHRA then again, revised the language adding that the engine must maintain its OEM configuration without taking into consideration the previous rule book change prior to the allowance of roller rockers that allowed the use of guide plates and rocker arm studs.

Re: Rockers for stock Eliminator 5.0 SBF
 

Do roller rockers really make any more horse power ? Or is it a matter of covenience. Seems to me that the stock rockers would be more reliable. Once there set-up I can't see how they could lose there adjustment.
Slickfoot

Re: Rockers for stock Eliminator 5.0 SBF
 

You would think they would make more power, but I 've seen several examples where they didn't.
The reason for the change is that NHRA doesn't want cars breaking on their track, and slowing down the show.
We've seen stamped sheet metal rockers split in two , or punch out the push rod cups, with the springs they allow you to run now.
But the main point should be.. Everybody ...or nobody.
Garden variety Chevies didn't come with screw in studs and guide plates. If they can modify the heads, why can't everyone else?
Shafts where shafts were, studs and guides everywhere else.
End of story.

Re: Rockers for stock Eliminator 5.0 SBF
 

I agree Mark, It should be the same for everyone. It's been 45 year since I raced in stock and was the same back than. They will cater to who will put the most asses in the seats. That being said, there has to be something done , because the two best legal roller sets the Ford M-6564-B351-C and the Comp 1052-16 are no longer made.
Slickfoot

Re: Rockers for stock Eliminator 5.0 SBF
 

Is the crane conversion kit worthwhile?

Re: Rockers for stock Eliminator 5.0 SBF
 

Thanks Bobby
I don't know anything about it. I'll will see if I can find on line and check it out.
Slickfoot

Re: Rockers for stock Eliminator 5.0 SBF
 

If I was determined to go that route I would can the conversion and just have the pedestal bases machined down for standard screw-in studs. http://www.mediafire.com/view/mq88m1...M-6564-All.pdf

Re: Rockers for stock Eliminator 5.0 SBF
 

Then why does the Marion Stephenson/Don Forester 1980 Olds get to run screw in studs and pass tech? The engine in this car has been thru teardown many times with screw in studs and guide plates, never having an issue.

The "must retain OEM design" wording in the rule book was put there to keep everyone from switching to shaft rockers. You are allowed to switch from pedestal to stud mount. You are not allowed to switch from pedestal or stud mount to shaft mount.

Re: Rockers for stock Eliminator 5.0 SBF
 

When I had my Mustang l made the stock rockers adjustable using screw in studs and guide plates and it was OK.

Re: Rockers for stock Eliminator 5.0 SBF
 

Well it seem as clear as mud ! If the Div. one tech person gets back to me, we get a ruling on this. Do you think they will put it down in writing ?
I have never been through a tear down,I don't know how crazy they get on a ruling by a different tech.
Slickfoot