Canfield cylinder heads screw-in rocker studs problem.

[Loves302Chevy]

What are your thought on using guideplates vs. self-aligning roller rockers? The reason I ask is that I bought some used Canfield 220 aluminum heads for a Gen1 SBC and discovered that the 4 center rocker stud bosses were welded and repaired using thinwall e-z lock inserts on both heads. Whoever did the repairs did an excellent job and they also installed the inserts for the rest of the 16 screw-in studs. I can't imagine what could of happened to cause this damage, but I do know the heads came off a 383 Chevy that was in a Nova running low tens, so I assume there was a big solid roller cam in there. The heads came with the triple valve springs and Jegs 1.6 ratio .150 offset intake/std exhaust roller rockers. I picked these up to use on a future, much milder street 383 for myself with most likely a flat tappet camshaft like an XE274H. I'm thinking that I should use the self-aligning rockers so that I could eliminate the guideplates and install the studs once and for all (with red loctite and thread sealer) and not have to work the threads anymore by having to adjust the Isky guideplates. I also have stud girdles to fit these heads (separate purchase), but I don't think the previous owner used girdles. What do you think? Mike.

 

[mathd]

If you can use guide plates i say go for guide plates with some chro-moly push-rods.
Stud girdle can't hurt too

 

[Indycars]

What are your thought on using guideplates vs. self-aligning roller rockers? The reason I ask is that I bought some used Canfield 220 aluminum heads for a Gen1 SBC and discovered that the 4 center rocker stud bosses were welded and repaired using thinwall e-z lock inserts on both heads. Whoever did the repairs did an excellent job and they also installed the inserts for the rest of the 16 screw-in studs.

I'm not sure why you are worried if the inserts were done properly. Steel threads should be considerably stronger than the original aluminum threads.

I can't imagine what could of happened to cause this damage, but I do know the heads came off a 383 Chevy that was in a Nova running low tens, so I assume there was a big solid roller cam in there. The heads came with the triple valve springs and Jegs 1.6 ratio .150 offset intake/std exhaust roller rockers. I picked these up to use on a future, much milder street 383 for myself with most likely a flat tappet camshaft like an XE274H.

You will need to change out the springs to something more appropriate for a hydraulic camshaft. Looks like to me that the heads are too big when considering the port size for that CompCams XE274H. Although I can't find any specs on that head, so I'm only guessing without more data.

I'm thinking that I should use the self-aligning rockers so that I could eliminate the guideplates and install the studs once and for all (with red loctite and thread sealer) and not have to work the threads anymore by having to adjust the Isky guideplates. I also have stud girdles to fit these heads (separate purchase), but I don't think the previous owner used girdles. What do you think? Mike.

 

[grumpyvette]

If you can use guide plates i say go for guide plates with some chro-moly push-rods.
Stud girdle can't hurt too

DITTO! I didn,t see this post before or Id have responded, but MATHD is correct Id use guide plates ans a rocker stud girdle in preference to self aligning rockers
and INDYCARS is correct you need to use the correct spring load rates and clearances and a rocker stud girdle will help stability

read these

viewtopic.php?f=52&t=181

viewtopic.php?f=44&t=2839&p=12739&hilit=adjustable+plates#p12739

viewtopic.php?f=52&t=4962&p=13816&hilit=rocker+stud+girdle#p13816

viewtopic.php?f=52&t=181&p=1065&hilit=rocker+stud+girdle#p1065

 

[Loves302Chevy]

Thanks guys. OK, I'll go with the guideplates and the girdle. And of course I would change to the proper springs set up with the correct geometry.

I'd like your opinions on whether to:
a) loctite the insert into the head and to use thread sealant on the screw-in stud, or
b) loctite the screw-in stud to the insert and when "dry" install this assembly into the head with
thread sealant (like the machine shop did). Yes, the guideplate must be already on the stud
with this option.

My concern is that if I loctite the insert into the head, then if for some reason I had to remove it, it would be nearly impossible. But, then maybe that is what I really want? Mike.

 

[grumpyvette]

Ive used either one of these two products, applied on clean dry rocker stud threads by dipping the stud threads just prior to assembly on those threads, waiting a minute for the stuff to start to get tacky,then screwing them in for decades

Ive never had a leak or loose stud, never had any issues removing them if required ,with the proper socket and breaker bar later either,
BTW, remember to visually verify the stud length and cut them a bit shorter if required you don,t want the lower end protruding into the intake port and any threads doing that do NOTHING to increase the stud rigidity but they sure can reduce port flow rates if left sticking down into the air flow path

ID ALSO POINT OUT THAT A ROCKER STUD GIRDLE ADDS A GOOD DEAL MORE STABILITY TO THE VALVE TRAIN
viewtopic.php?f=70&t=4836&p=13219&hilit=indexing+plugs#p13219

its very common to find you'll gain a couple horsepower with the addition of a rocker stud girdle employed,
as youll have both more precise valve train control and less deflection, Ive seen guys instantly gain an extra 150 rpm-200 rpm,
before they started feeling valve float or loss of valve train control and its certainly less stress on the cylinder head casting and rocker studs.
the one thing ID suggest is that before you buy any rocker stud girdle you ask questions, many cylinder head designs use non-standard rocker stud spacing.

 

[Indycars]

Ive used either one of these two products, applied on clean dry threads by dipping the stud threads just prior to assembly on those threads, waiting a minute for the stuff to start to get tacky,then screwing them in for decades

Ive never had a leak or loose stud, never had any issues removing them if required ,with the proper socket and breaker bar later either,

I assume you are talking about the rocker stud threads, what about the inserts ???

Seems like blue loctite would work well on the thread inserts.

 

[Loves302Chevy]

Thanks Grumpy. I never thought of using either one of these - and I have both.
I just didn't want to red loctite the insert in and have to use oxy-acetylene to
get it out if I ever had to. Mike. :mrgreen: :mrgreen: :mrgreen:

 

[mathd]

What insert are you reffering to?
on my guide plate setup all i have is.. guide plates and rocker stud nothing else.
I just set the guide plate so the pushrod/rocker stud/valve tip is aligned as much as possible then i tighten the rocker stud so it dont move.

 

[Indycars]

What are your thought on using guideplates vs. self-aligning roller rockers? The reason I ask is that I bought some used Canfield 220 aluminum heads for a Gen1 SBC and discovered that the 4 center rocker stud bosses were welded and repaired using thinwall e-z lock inserts on both heads. Whoever did the repairs did an excellent job and they also installed the inserts for the rest of the 16 screw-in studs.

In his first post he talks about the threads for the rocker studs being repaired using inserts.

 

[mathd]

What are your thought on using guideplates vs. self-aligning roller rockers? The reason I ask is that I bought some used Canfield 220 aluminum heads for a Gen1 SBC and discovered that the 4 center rocker stud bosses were welded and repaired using thinwall e-z lock inserts on both heads. Whoever did the repairs did an excellent job and they also installed the inserts for the rest of the 16 screw-in studs.

In his first post he talks about the threads for the rocker studs being repaired using inserts.

Ahhh, ok thanks for making it clear to me.