Using guide plates to keep rocker tips over the valves works. Although somewhat avoided the self-aligning rockers seem to do the job and, in my opinion, are putting "control" where needed.

I have noticed that some full rollers have some side-to-side movement. So using the pushrod/guide plate method leaves some room for movement at the valve tip/rocker tip interface.

On the other hand (or side) using a self-aligning roller rocker would allow some movement on the pushrod side.

It seems it would be all around best to "control" movement on both side of the rocker. I admit it may be a slight overkill but would there be any problems as long as the guideplate was adjusted so the "play" on the valve tip was consistent with the push rod? It would require an adjustable guide plate to allow each rocker/valve/pushrod to be adjusted as needed. Any thoughts???

 

You're flirting with disaster for no potential benefit.
The roller tip doesn't have to be PERFECTLY centered on the valve stem.
IMO, guideplates and hardened pushrods are the way to go. Any wear at that interface is cheaper to deal with than the valveguide wear you get with SA rockers and stout valvesprings.
For OEM/mild spring pressures, the SA rockers are perfectly acceptable.

 

Guide plates + self aligning rockers = Broken parts.

 

ive been following a build that used both, and i'm just waiting to hear about the failure.

 

Years ago, I built a 350, with 083 heads. At the time from what I read all the centerbolts used self aligning rockers, so thats what I went with.

I did not know the 083 heads had an oval shaped pushrod hod designed to keep the pushrod aligned.

Needless to say, this mild street motor kept breaking, literally breaking hardened pushrods, and we could not figure out why.

 

Bearing in mind,
the factory alum 113 heads as used on the Vettes and ZZ4 engines have what " appear" to be guide plates with SA rockers but they are only assembly plates to hold the pushrods in place when the engine is being assembled.

 

But why? If they are not aligned properly, yes. It seems that if the tolerance on both ends were alligned it would be ok.

Now I don't actually use this combo. It will be interesting to know if someone has or hear back from those who try it.

 

bind the pushrod and see what happens

 

You've already heard back from Johnny Blaze who accidentally "tried" it.
Aligning everything at ambient temperature and not considering dynamics and deflections at operating conditions doesn't mean squat. A basic understanding of mechanical systems would convince you that it's a bad idea to restrict the system at two locations, ignoring the dynamics/harmonics/deflections that are going to occur. And I can tell you don't have that understanding from your use of the word "tolerance".

Forget it, ok?
It's like asking why is water wet.

Maybe this will help: Do you think the pushrods stay straight at high rpm?
.
.
. ..........they don't.

 

I think there may be a vid floating around showing pushrods in action. Heard there was one but havent seen it yet. From what was described however will shock most ppl. Amazing the rods stay in one piece

 

083's are iron L98's right? They did come with self aligning and thats what i used as well. That pushrod slot hole isnt really a guide tho, i never had issues when i ran self aligning 1.6's on stock pushrod/cam L98 heads.

For any highperformance build, you should stick to guideplate and non self aligning, and if you can afford it, go shaft rockers. Very nice pieces, i am convinced thats the best way to go for best geometry

 

i've been running self-aligners with no guideplates for years with no problems. from my understanding, its one or the other, cant run both or you'll put the valvetrain in a bind and break parts. i agree, pushrod deflection is something people fail to take into account.

ever look at some nascar pushrods? man, they're huge!

http://trendperform.com/products/pus...onents/nascar/

http://www.competitionplus.com/drag-...-wall-pushrods

http://www.ebay.com/itm/NASCAR-PUSHR...-/360441811586

 

Absolutely.
On my 7100 rpm LT1, I think I'm about at the limit of a guideplate setup. Running stiff 5/16" pushrods, about 155 lbs on the seat, .617 lift, well over 400 lbs over the nose. If I were solid roller and higher spring pressures, shaft rockers it would be. Stud girdles are a compromise, but IMO a poor one and a PITA compared to shaft rockers.

 

They're perfectly fine for mild valvetrains. A lot of them out there operating with mild HR setups up to ~6500 rpm.

 

I have shafts on my hyd roller. .640", 180 lbs seat, 450 open, heavy valve, 3/8" pushrods, morel lifters and 24 psi boost lol hit 7200 rpm and it will go higher if i wasnt afraid to push it. Cant beat the proper geometry and rigidity a shaft system gives you. Shame they cost so much but mine are relatively low buck at sub 750$. And dont need guideplates

 

That's what I thought too.
Check out this thread.
https://www.thirdgen.org/forums/tpi/...gning-not.html

 

I dont recall what my heads had for pushrod holes but i swear they had the lips on the ends of the rocker that all self aligning rockers have.

 

My stock rockers are long gone, but it would be interesting to see what's on a stock engine. I have a 1990 truck motor that appears stock. I'll go pull a valve cover off and see what it looks like.

The slot vs hole makes sense too me, and explains why my old engine kept breaking pushrods.

The pushrods were comp hardened. Had a small roller cam with gm lifters, matching springs and scorpion self aligning roller rockers.

 

800 miles on my fresh build, with 083 heads, no guideplates and non self aligning rockers.

When ihad them freshened up, the machinest even said, make sure you don't run self aligning rockers with these heads.