[dataway]

Here are some photos.

Poly-locks with the drip cover are going to be a no go it looks like. The drip dimples practically touch the top of the studs.

I decide to lap a few of the Comp roller tips and see what the result was. Used a slow speed drill, valve grinding compound and a little arbor setup I made. Fairly dramatic difference after lapping. When dry, and unlapped, if you put the ball washer in the rocker and pivot it with your finger you can feel the coarseness, and feel it occasionally hang up. No better with oil. After lapping about two minutes, rocking the arbor back and forth to mimic rocker arm movement, pull it apart, clean it, and there is no more coarseness, the ball washer slides smoothing in the rocker, with oil, feels very slick and smooth.

One picture shows the high areas that were taken down by lapping.

I saw quite a bit of variance from one rocker to another, some very good, some not so good. I'm guessing the failures noted were pieces that were unusually bad for some reason, combined with higher spring pressures, creates a hot spot that escalates.

I think the Comp roller fulcrums are formed as good as OEM, problem is, the texture of the metal on this CC pieces is considerably rougher than the stamped steel OEM pieces. Combine that roughness with a malformed piece, some heavier than stock springs and I could see how failures could take place. I think the lapping will make all the difference in the world. The actual roller tip on the set I have all looks good, round, rotate smoothly, installed in the rocker straight and perpendicular to the groove. Certainly not a show piece of craftsmanship, but with lapping should be as good as OEM, although I don't know if you could put 100K miles on the tips like you could OEM rockers.

[78w72]

you can probably get by with the thick 1/4" felpro valve cover gaskets but maybe the drippers hang too low.

& lapping the rocker nuts is a good idea, ive read about some of teh heat issues with these rockers... but i have 2 sets in use for a long time & no heat blueing or other indications of problems.

[dataway]

Originally Posted by 78w72

you can probably get by with the thick 1/4" felpro valve cover gaskets but maybe the drippers hang too low.

& lapping the rocker nuts is a good idea, ive read about some of teh heat issues with these rockers... but i have 2 sets in use for a long time & no heat blueing or other indications of problems.

There doesn't appear to be one in my set that I could point to as being bad enough to fail. And seems as though if they last the first 100 hours ... they would probably last a long time after.

[78w72]

some guys here hate them & have issues with teh nut area turning blue from heat, never really heard of a true failure as they keep operating even if they got hot.

the one set i have are over 20 years old & been in 2 engines, a 455 that got the day lights beat out of it back in the 90's & now in my current 400 for almost 10 years & they look like new still. im sure yours will be fine after lapping in.

they also sell actual spacers for the valve covers if the 1/4" gaskets dont give enough clearance.

[tom s]

You can get thicker aftermarket gaskets.I run H&S full roller 1.65s under stock covers all the time.Tom

[78w72]

ytes the 1/4" felpros i mentioned, & tin indian makes a 1/4" rubber gasket too.

i run h/s full rollers with poly locks on stock valve covers too... but i think the drippers might create an issue, based on his pic it doesnt look like the 1/4" gaskets would provide enough clearance for poly locks.

[dataway]

Keep in mind the drippers attach to the head ... so a thick valve cover gasket is no help. I'm most likely going to go with the BBC crimp nuts, if any of them are in doubt, they are easy enough to replace. And the likely hood is that if this engine starts and runs properly, it will not be taken apart or modified for many years. Possible it will need a valve adjustment after it's got some run time. But that will hopefully be the last time the valve covers are off for a long time.

When you look close at those drippers you see why they used them ... it must direct a ton of oil from the pushrod up on to the shield where it runs directly down onto the stud/pivot.

[Formulajones]

I haven't used those drippers in a Pontiac build in decades. Didn't even realize there were people still trying to utilize those things.

Removing those would make your life much easier. Then run any poly lock/rocker arm you want, double the valve cover gasket for clearance and you're done.

[HWYSTR455]

I initially used the roller tip rockers on my Olds build, I got a deal on the kit to convert to adjustable valvetrain. I was aware of the issues with the fulcrums, rockers, etc, and did the same, close inspection, and lapped the fulcrums into the rockers in the same way.

I also touched up the slots, there was casting flash, and some of the slots were not centered properly, which caused them not to ride on the valve tip right. Some the roller was off the tip to one side or the other, but you can only touch them up so much without making the slot too big. I eventually switched over to the Scorpions. (I need to check those now that I think bout it, they have probably 15k miles on them now).

Keep an eye on the studs, where the rockers are, and if you start seeing wear there, you should probably replace, or work the slot a little more. The nuts can back off too, so you might be taking a cover off a lot sooner than you think you might have to.

I will look, I might have some poly locks, if I do, I will PM you, will send them as a project donation.

.

[dataway]

Yes I love the drippers, I think they might be there for a reason . They didn't use them on anything but the 4bbl engines correct? Back in the day pulling apart 2 bbl 350's and such I don't recall ever seeing one there.

I could be way off base ... but people have rockers failing at the pivot, but have removed the device the factory installed to oil the pivots, sometimes I feel there might be a connection there somewhere. The design of those things put a LOT of oil on the pivot, must have kept a good tablespoon of oil in the rocker recess all the time.

Did the BBC that used the crimp nuts have a bottle neck stud that allow the nut to be torqued down like a stock Pontiac? Just wondering if the nuts were a problem in regular use on the BBC, or if they had some other way they kept them from backing off.

HWYSTR ... Thanks, if it comes down to that I might take you up on that offer.

[Formulajones]

Originally Posted by dataway

Yes I love the drippers, I think they might be there for a reason . They didn't use them on anything but the 4bbl engines correct? Back in the day pulling apart 2 bbl 350's and such I don't recall ever seeing one there.

I could be way off base ... but people have rockers failing at the pivot, but have removed the device the factory installed to oil the pivots, sometimes I feel there might be a connection there somewhere. The design of those things put a LOT of oil on the pivot, must have kept a good tablespoon of oil in the rocker recess all the time.

Did the BBC that used the crimp nuts have a bottle neck stud that allow the nut to be torqued down like a stock Pontiac? Just wondering if the nuts were a problem in regular use on the BBC, or if they had some other way they kept them from backing off.

HWYSTR ... Thanks, if it comes down to that I might take you up on that offer.

Older BBC have adjustable valve trains so no bottle neck studs on those. Later models up into the late 1980's however did have a non adjustable valvetrain. I have a new 502 crate engine sitting here with it's factory roller cam, rockers are non adjustable on those too.

The drippers I'm not so sure. You see them on some Pontiac engines, others you don't. Not sure why that deal was hit and miss for Pontiac. In any event, I've never viewed them as necessary when you have many other brand engines out there not using them and they run just fine. The valve covers on SBC's didn't start utilizing drippers until 1970 on the solid lifter engines. BBC's had drippers spot welded on the bottom of the steel valve covers but I've seen so many of those removed for more rocker clearance, and so many reproduction valve covers that don't even have them to start with.
The rockers get a ton of oil, matter of fact, if you ever prime an engine with the covers off you'll see they are flooded in no time. My 69 Z/28 never had drippers from the factory, and we haven't built our Pontiacs with them here in decades, and they get a ton of miles on them. We are usually building performance type stuff here and the Pontiac style drippers always get in the way of something. But I completely understand if you want the drippers, by all means keep them in place.

[dataway]

Anyone ever thought of using a jam nut on top of the BBC crimp nuts? There is room after they are adjusted to put probably a 1/4" thick, 7/16 jam nut on the stud. Tons of the vintage stuff I've worked on used some type of jam nut for keeping valve adjustment.

Although I would hate to see one come loose and float around the engine internals. The bike engines I built had rocker adjustment at the valve tip end. Rocker was threaded, a hardened steel tappit screwed in and was secured with a jam nut ... you could turn them 14,000 rpm and they wouldn't budge.

[Formulajones]

Not a bad idea Dataway, and better than those crimp nuts by themselves.

Polylocks are dirt cheap to buy separately so I just prefer to use those, just so much easier to adjust valves with them, besides they always come with the full rollers anyway.

[ponyakr]

" Anyone ever thought of using a jam nut on top of the BBC crimp nuts? There is room after they are adjusted to put probably a 1/4" thick, 7/16 jam nut on the stud..."

Don't see any problem with that. 2 crimp nuts may be even better. If a 2nd crimp nut is too thick, you can grind 'em down some.

I suppose that if you really wanted to use poly-locks, you could fab up some shorter studs & nuts. I think some of the poly-locks for alum rockers are a bit shorter. But, if not short enuff, just grind 'em down.

These are .865 tall.

https://www.summitracing.com/parts/c...s-16/overview/

These are .874 tall.

http://www.ebay.com/itm/Wolverine-WG...dZFOa7&vxp=mtr

The shortest 7/16 studs I know of are 1.68. So, if you need 'em any shorter, you'll have to shorten 'em yourself. I have no idea how short the studs & poly-locks would need to be to do what you want.

http://www.jegs.com/i/JEGS-Performan...20584/10002/-1

[dataway]

Those .865s would almost work ... would need to shorten the stud the same amount as the set screw is tall.

I did find quite a selection of 1/4" thick jam nuts, and some 5/16" thick lock nuts, both "nyloc" and the type with the segmented locking top.

Without going down and checking ... my guess is that jam nuts are not common used because getting a wrench down in the rocker arm well to hold the lower nut while you tighten the jam nut might not be possible with normal tools.

So .. there were BBC that had adjustable valve trains and just used crimp nuts to secure the rockers?

[78w72]

Originally Posted by dataway

So .. there were BBC that had adjustable valve trains and just used crimp nuts to secure the rockers?

yes, BBC's used the crimped & they work great. probably not a multi use thing but i have them on one of my t/a's for almost 10 years & they havent moved a bit, lots of drag strip runs & hard street use.

no need to over think rocker nuts... if the poly locks fit use them, if not the crimped nuts are perfectly fine.

have you considered the 1/4" thick gaskets or spacers?

[dataway]

My problem is the dripper shields ... they attach to the heads so thicker cover gaskets won't help, and I insist on using them

I'll most likely be going with the crimp nuts and see if any problems arise. I don't really expect them to move, they are pretty snug on the studs.

[ponyakr]

"...the crimped nuts are perfectly fine..."

They are not ALL perfectly fine, as I, and many others, have discovered. Some will stay put. Some won't.

I assume that the EXACT size and/or condition of both the stud & nut could determine whether the nut will back off or not.

This may have already been mentioned. But I'm not gonna go back thru the thread to find out. Can you just use shims under the drippers, plus thick valve cover gaskets ?

[dataway]

Pony ... hey... freakin good idea. Probably have a decent amount of room to shim up the drippers before they contact the valve covers ... good idea.

[ponyakr]

Edelbrock 7590 VC gaskets are 5/16 thick.

https://www.summitracing.com/parts/edl-7590

$23.99 + tax, from Advance Auto Parts, is the cheapest shipped price I can find.

https://shop.advanceautoparts.com/p/...E&gclsrc=aw.ds

$26.88 shipped from an Amazon seller.

https://www.amazon.com/Edelbrock-759.../dp/B000VDLSD4

http://butlerperformance.com/i-24453...-edl-7590.html

Butler also sells some 5/16 cork gaskets, $5 cheaper. Don't know what the shipping charge would be.

http://butlerperformance.com/i-24453...tegory:1234816