Rockers: stud/pedistal mounting and more ?'s

plastic_cow

New Member
Sep 10, 2003
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Oshkosh, WI
So I got a decent pair of heads from a friend, machined, new seals & stems .015 over, valve springs are new, blah blah blah, got 'em cheap too... like $200 for both from a friend after he had the machine work done on them... problem is - they're stud mounted rockers, (late 70's/early 80's heads) and I have pedistal mounted (1988)
Is there a way I can convert? (Without it being more expensive than buying new rockers)
I've heard bad things about alum. rockers folding up on people, is it crap or is it a geniune consern in a 'stang?
I don't have much money left to drop into this project... but I really need to have the job done relitively quickly... within a week or two... so 'saving up' isn't much of an option, if I need replacement rockers I'd like to spend under 200 (incl. shipping) Any idea on where to find them? Links would be appreciated. (3/8" if I'm correct)
What's the difference between rockers that are 1.6 and 1.7... and if I have a GT-40 intake, and the heads above, what would you recommend?

Thanks, sorry about the mess of questions, I'm just really confused and flustered... I want to drive my stang before it snows in Wisconsin...
Thanks for the help!
 
The difference in 1.6's and 1.7's is the ratio of the rocker. "1.6" refers to the fact that for every 1 unit of lift the pushrod gives you on the short end of the rocker, the long end of the rocker pushes down with 1.6 units of lift on the valve stem. Obviously, a 1.7 ratio rocker gives you 1.7 units of lift - so for the same cam, you get a bit more peak lift, and a bit more valve-open duration. If nothing else changes, you probably also side-load the valve stem a bit more with the higher ratio.

On an engine like yours, you needn't worry about the aluminum rockers out there 'folding up'. That might happen to a cast rocker used with springs that are too strong for it. But MANY racers reliably use quality forged aluminum rockers with springs MUCH stronger than yours.

The challenge you face is that the hole drilled for the rocker stud is larger than the bolts provided for most pedestal mount rockers. I think you have 3/8" holes, and most pedestal mounts take 5/16" I believe. Easiest would be to simply pick up a set of used stud mount rockers. Check the forum classifieds - they are for sale all the time.
 
I would go stud mount. They are cheaper then pedistal. You can find them used for like $180 for a good set. I know the Trickflow rockers are $230 new. If you go with Harland Sharp they are $198 in jegs right now. I would go with a 1.6 rocker because you want the cam to do the lift, not the rockers. Also you will gain horse power from aluminum rockers.
 
What is your budget?

Steeda makes bolt down Pedestal rockers that are mini shaft mount rockers. Very strong. $350 new, complete set.

http://www.steeda.com/store/-catalog/shaftrocker.htm

shaftrockers.jpg
 
Stud mount have considerable advantages over pedestal, the best being the use of needle bearings. Consider it an upgrade/performance mod at the same time - it's the best excuse for getting to replace something :)