Stud mount vs. Pedestal mount

Topic: Stud mount vs. Pedestal mount (Read 6566 times) previous topic - next topic

Stud mount vs. Pedestal mount

February 24, 2005, 08:19:38 AM

Can anyone post picks to show the diference in these two rocker styles, and what some advantges/disadvantages are between the two?

Inquiring minds want to know!

Re: Stud mount vs. Pedestal mount

Reply #1 – February 24, 2005, 09:25:32 AM

You probably figured out they're the same price, right?

Stud Mount: The studs are stronger and more dependable than bolts, so there's a plus. They're also a little quieter than bolt-ons. The down side is that you will need to also buy the studs at the extra cost. There can be a little trickiness to this as well...there's 3/8" and 7/16" for Ford heads, for example. So everything must match.

Bolt-On: Just like the Dark Side of the Force....quicker, easier, more seductive. Just bolt them on like the name says. They are noisier though. And the potential for the bolts to back out is higher.

A few general things about roller rockers. It's so easy for a roller tip to slide off the top of the valve that you need something to keep the rockers in place. For most situations you'll need machine work to the heads to shim down the pedestals for guideplates (you MUST run guideplates with most roller rockers). You'll also need to run hardened pushrods made for use with guideplates. And of course you'll have the added expense of buying the guideplates and hardened pushrods. Some aftermarket roller rockers have a ridge on the edges of the rollers, to theoretically eliminate the need for guideplates. The ridges keep them from slipping off the valves. They're a little more expensive but are the way to go if you don't want to do the extra machine work. There's also shaft-mounted rollers that are really, really expensive but do not require machining, and are the ultimate in bolt-on longevity for roller rockers.

On the convertible I am running ported E7 heads with 7/16" stud-mounted Crane 1.6 roller rockers, Motorsport guideplates and Crane hardened pushrods. It's a rock-solid combination that has been very dependable. The Crane rockers (and I'm sure, other companies by now) have the double-set locking screw setup that makes it sooooooo easy to set the valve lash and keep things locked down nicely. That's the setup you'll want to use.

Re: Stud mount vs. Pedestal mount

Reply #2 – February 24, 2005, 09:04:12 PM

To be honest it depends on what heads you are running. Are you going to run stud mount or bolt down mount rocker heads? If you are running stock E7 heads than I would simply run a set of Crane 1.7 Cobra boltdown rockers. For the money you cant beat them. Now if your going with aftermarket heads(AFR, World/Dart, TW, Edelbrock,etc), they will usually come ready for stud mount rockers. Stud mounts are much easier to install, simply bring to zero lash and then preload them(I go 1/2 turn). Tighten the locks and your set, no shimming and checking torque and all that. I run Scorpion stud rockers, they are good quality. In other words, I wouldnt pay to have someone install studs/guideplates on a set of stock heads, I would simply run some aftermarket boltdown rockers. However, if you are deciding between stud/boltdown heads, go stud.

Re: Stud mount vs. Pedestal mount

Reply #3 – February 25, 2005, 04:47:43 PM

and a couple pics of my 289/302 build for a friend of mine........
the only tricky part of these roller rockers is the babysitting of your set screw on each valve till you get it right. If you use these types of roller rockers,, id suggest you dont add silicone to the valve covers till you think you have all the rockers quite.

Re: Stud mount vs. Pedestal mount

Reply #4 – February 25, 2005, 08:38:52 PM

I think i'm gonna agree on having one pic of each! I get it but I don't get it for some reason. I'm sure it's not the explainations, just that i'm a visual learner type and need to see what's being talked about. So if ya got pics, post 'em!!

Re: Stud mount vs. Pedestal mount

Reply #5 – February 25, 2005, 09:29:24 PM

well,, the only picture left not shown is whats under your valve cover now,, pedistal type. Those take a bolt/fulcrum that passes through the rocker arm and tighens to the hole in the head.

and only one more variation would be that the below picture would have a roller wheel where it touches the valve stem.

looking at the first pic of the roller rocker with the 289 heads.........previous post above
drop the rocker in place over the "STUDED HEADS YOU SEE"
add your fulcrum
add that big hex nut
add the set screw in the top of the hex nut
postion your pushrod
snug down the hex nut
tighten the set screw
rotate engine and re adjust each rocker with valve closed
tweek in your set screw after a few warm up's cause the lifters will pump up most slack ect ect.

looking at the second pic of chris's stock rocker there are three parts
the bolt
fulcrum
rocker
no studs present at all.
no roller where the rocker touches the valve.

courtisy of chris1987lx

now,, need some more cofussion? remove the valve cover off an old plymouth duster,,like 1974 and your will see that these types of valves are adjustable by a lock nut and bolt where the rocker and valve stem touch.,,,just another variation of whats out there except these mopar and not to be poked fun of

Re: Stud mount vs. Pedestal mount

Reply #6 – February 26, 2005, 12:59:42 AM

Actually, I really hadn't checked into pricing and such, as I really had no idea what I would be checking prices on. The photos made things a little clearer as to visually see what the differences are.
I'm just starting the planning stages of a stroker 351 build, and I'm thinking either AFR's or TW's, but had no idea what the differences were between stud mount and pedestal mount heads were. But when Eric and chrome302jr mentioned "bolt-down" and "shaft-mount", I'm really letting myself get cornfused now.

The attached pic is of a D8OE head that I have. When I got theses heads there were no rockers included. From what has been said, therse are a shaft mount set-up? And if I go aftermarket with this type of set-up, I should invest in guide plates and hardened push rods?

Sorry for the :dunce: type of repetitive q's but to many choices hurt my wittle bwain. I swear, sometimes I feel that this is my brain on life :flame:

Thanks for bearing with me on this folks! :bowdown:

Re: Stud mount vs. Pedestal mount

Reply #7 – February 26, 2005, 07:28:58 PM

K, jcassity... The first pic you posted was stud mount, the second was pedestal. Now if I understand right, heads have to come designed for stud mount rockers? And for pedestal mount the pedestal is more or less the stud? And what do the stock 302 heads come with?

Re: Stud mount vs. Pedestal mount

Reply #8 – February 26, 2005, 10:54:03 PM

more specifically, our engines for the models and years we deal with are stock pedistal.

Pedistal with a roller where it touches the valve
pedistal with no roller,, just plain friction type.

the first pic is..
where a threaded 7/16 bolt is screwed in/ancd to the head
this means the FLUCRUM does not rest on the head.
this also means one side of the rocker rests on the pushrod
the other side rests on the valve stem.
assembley-
drop rocker on valve and pushrod
add fulcrum
add nut
adjust nut till there is slight tension and stop
tight lock or set screw in the top of nut.
the set screw bottoms out on the top of the stud.
run engine a while then retweek the set screws.

the second is on a 3.8L on chris1987lx , same on the SO 5.0
differences in assembly will be obvious.
place rocker on the pushrod and valve stem
insert fulcrum (which rests on the head)
insert bolt and tighten up till it stops (around 20ftlb i think.

the third type of rocker is laying there sideways. It will be positioned on a long runner tube which is accompanied by other rockers just like it to the tune of 12 for a slant 6. Its a friction type and as you can see, there is a small nut and an adjustable screw which allows you to gap your valves. You would use a feeler guage on these types and i dont really recall the tolerances but they needed to be gaped just like points.

the heads you show could be studed very easily by just installing a threaded bolt of a grade 8 or better. the threads per inch here are the second important part. The more threads, the better adjustment range you have.

All in all,, you gotta just drop this issue till you handle and feel and see for yourself cause there aint no real explaining it till you see all the variations. Bone yard hoping is a good place to get a better look at what different types of valve trains are out there. Once you get most of it down,, you soon learn why it is that our RPM range is so limited with the average tapet valve system.

once you see the problems,, you'll soon wanna invent.,modify,,change,,adjust, and it never really stops.

Re: Stud mount vs. Pedestal mount

Reply #9 – February 27, 2005, 05:50:44 AM

Quote from: jcassity

All in all,, you gotta just drop this issue till you handle and feel and see for yourself cause there aint no real explaining it till you see all the variations. Bone yard hoping is a good place to get a better look at what different types of valve trains are out there. Once you get most of it down,, you soon learn why it is that our RPM range is so limited with the average tapet valve system.

Are you saying we who have questions shouldn't bother asking, and just figure it out for ourselves? :bs:
Funny, I thought the whole purpose of message boards was to have a place to ask questions, give answers, and in general share knowledge about a common interest?
As for my original question, I asked about general differences between two types of setups, and how to identify them. Simple answers like "Hey first pic shows stud mounted type, second shows pedestal type...." would have sufficed, along with "this type is stronger than this, etc, etc."
Eric and chrome302jr. were cool enough to go a step further by explaining some personal experiences and some additional hardware that can be associated with performance setups. For that I thank them.
What I don't need is BS, like 'figure it out yourself', and I don't think anyone else here deserves that kind of mentality. It's kind of hard to go galavanting around bone yards (which I would love to do)when I have a 16 month old daughter to care for, so you don't have to be bothered with my questions.
You post alot of buttstuffitical, engineering sounding mumbo jumbo expecting the average guy to understand it, then tell them to figure it out for themselves cause they didn't understand much of what you said in the first place.

Yes, I'm done venting now.

(Flame off....)

Re: Stud mount vs. Pedestal mount

Reply #10 – February 27, 2005, 07:47:52 AM

Quote

Can anyone post picks

Who, me????
Sorry the rockers don't actually move, but I'm tired.

I think everything was explained already, but anyway....

Stud mount:
Stud is threaded into head, and becomes "as one" with it.
Rocker is dropped over stud, sits on valve tip and pushrod tip.
Fulcrum is dropped over stud, sits loosely in rocker.
Nut is screwed down stud, until all lash is gone.

Pedestal mount:
Fulcrum is dropped through rocker, pokes out the bottom.
Bolt is dropped through fulcrum, pokes out the bottom too.
Assembly is positioned on head, bolt tightened until bottomed.
Fulcrum becomes "as one" with head.
Shims under fulcrum and/or different pushrods used to adjust lash.

Shaft mount:
All rockers are assembled on shaft together.
Entire assembly is bolted down all at once.
Screw adjusters or different pushrods used to adjust lash.
.

Re: Stud mount vs. Pedestal mount

Reply #11 – February 27, 2005, 12:53:49 PM

Quote from: Warbird9

Yes, I'm done venting now.

(Flame off....)

good, cause i dont really understand why you did in the first place. Its only a matter of time before words without physical substance become overkill.
I only thought it was a good point in the coverstation to bring up the next step,,,,,,ie - time to investigate. I thought you might come back with a "yea, i hope to real soon" or maybe "theres a bone yard near by, maybe ill do that here real soon cause i just gotta sort it out". Thats what i had to do and some seem to evade the work part of it by thinking the computer can tell them all they need to know ,, and when something bad happens then you can blame it on a computer somewhere.
instead,, you get worked up. Nonesense., i felt comfortable handling the first half of your question. Notice i did not even do a flyby on your second half cause im not qualified.

Some believe that the computer is the be all and end all when in fact, manual labor will soon demand a preimium dollar cause there aint none of us going to know which end of the hoe to grab or the difference between a threaded rod or a connecting rod.
Right now, most of us dont know which end of a horse the hanes go on.......and if you dont know, then your there.

Back to the topic,,, there would be one other type of rocker out there that involves overhead cams and they eliminate a lot of typical parts you'd see.

as for the kids part,,, been there done that ,, still doing that......
you cant walk around a junk yard with and 18mo old? you'd be surprised how many brownie points you'd get for involving your kids in your life.

Re: Stud mount vs. Pedestal mount

Reply #12 – February 28, 2005, 12:10:23 AM

MasterBlaster......THANK YOU! That was what I was looking for. Thanks to you, Eric and chrome302jr for your input. Most informative.
As far as I'm concerned, thats all I needed to know.

Ther are a couple of things, however, I feel still need to be addressed.
jcassity:
1.

Quote from: jcassity

"Thats what i had to do and some seem to evade the work part of it by thinking the computer can tell them all they need to know ,, and when something bad happens then you can blame it on a computer somewhere." "Some believe that the computer is the be all and end all when in fact, manual labor will soon demand a preimium dollar cause there aint none of us going to know which end of the hoe to grab or the difference between a threaded rod or a connecting rod.
Right now, most of us dont know which end of a horse the hanes go on.......and if you dont know, then your there."

If you have such a problem with using the internet as an information tool (which is exactly how I view the internet, as a tool) then why are you here? It sounds to me like you belive that the internet will lead to the fall of civilization (which it very well could), so why would you contribute to that downfall be trying to answer q's?

2.

Quote from: jcassity

Its only a matter of time before words without physical substance become overkill.
I only thought it was a good point in the coverstation to bring up the next step,,,,,,ie - time to investigate.

How do you figure my post had gotten to 'overkill' status? There were only three posts aside from yours that had information regarding the question!

3.

Quote from: jcassity

as for the kids part,,, been there done that ,, still doing that......
you cant walk around a junk yard with and 18mo old? you'd be surprised how many brownie points you'd get for involving your kids in your life.

First of all, taking a toddler to a junkyard? That's just downright assenine, let alone completely irresponsible! Second, my 13 year old step son has helped me plenty tearing down my parts cars. I don't consider it brownie pts, it's an honor! An honor that that he chooses to spend time with me, sharing a common interest. Hmm, kinda sounds like a message board community, the sharing a common interest part. Hell, even the honor part. At least with the bulk of the members I feel it's an honor to share in the wealth of knowledge the people here are willing to share. Well, at least the people who don't act condescending about it.
jcassity, you no longer irritate me. You just plain bore me.

Alright, time to shut this one down. "Lock 'er down warden!" :locked:

Re: Stud mount vs. Pedestal mount

Reply #13 – February 28, 2005, 01:02:43 AM

here's where this went bad.......Ill quote myself from a previous post incase anyones confused....

"""""All in all,, you gotta just drop this issue till you handle and feel and see for yourself cause there aint no real explaining it till you see all the variations."""""""

ill attempt a reword in order to smooth out the edges...........

All in all,, there are many types of rocker systems out there so you might wanna take the information you have from here and compare to the real world like in a bone yard or somewhere.

im a nice person and id give the shirt off my back to you but man your really wiggin on something not meant as an insult, it was meant as a constructive suggetion. Ive noticed over the past few years that even that part of respect for others is becoming lost in the past as well. if someone shared a bunch of stuff with me then told me where the physical evidence was at,, id be on it like stink. Matter of fact, your no where near g me or anyone off so no need on locking a thread that aint up in flames yet because of one person.

i really wish you had not come on so hard back there cause i had no idea you were offended, then you busted my balls before i had a chance to say sorry.