Roller Rocker Arm Situation

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Ronno6

Full Access Member
Joined
May 14, 2018
Posts
438
Reaction score
126
Location
South Mississippi
First Name
Ron
Truck Year
1984
Truck Model
C10
Engine Size
355
I am not really able to center the roller tips of my Scorpion roller rocker arms
over the center of the valve stems to my satisfaction.
I have read that this can be a common problem with aftermarket heads.
Question is: would it be better to get adjustable guide plates, or use self aligning rocker arms??

As is, the arms cant a bit to come close to aligning.
The Scorpion arms are very wide and square at the top end, and this is making things really
close to rubbing on the valve covers.

However, the alignment issue is first and foremost......
 

climb-101

Full Access Member
Joined
Mar 12, 2018
Posts
262
Reaction score
278
Location
montana
First Name
seth
Truck Year
974
Truck Model
c2 crew cab
Engine Size
6.0 LS
are they too close or too far, you can color the tip of the valve and put the rocker arm on and see exactly where they are hitting through the cycle.

are the pushrods the right length?
 

Ronno6

Full Access Member
Joined
May 14, 2018
Posts
438
Reaction score
126
Location
South Mississippi
First Name
Ron
Truck Year
1984
Truck Model
C10
Engine Size
355
are they too close or too far, you can color the tip of the valve and put the rocker arm on and see exactly where they are hitting through the cycle.

are the pushrods the right length?

Pushrods are the correct length.
When I set the valve covers on the head, the topmost edges of the rocker arms (toward the intake manifold) will contact the valve covers. If I move the valve covers up slightly, I can avoid contact.
But, not by much.
The Scorpion 1001 rocker arms are very wide and squared off at the pushrod end.
You must be registered for see images attach

As the valve train continuously widens c to c from lifter to valve stem, the rocker arms are not parallel to each other as they span from pushrod to valve.
My crude measuring show the following c to c dimensions at critical points:

Cam lobes (hence, lifters) 1.575"
Guide Plate pushrod slots: 1.75"
Rocker arm studs: 1.775"
Valve stems: 1.95"

This non parallel orientation means that the rocker arm ends will not be in line with each other, but rather, form a wide "V" or inverted chevron shape which leaves the outer corners of each pair closer to the valve covers.

I can either grind off a tiny amount from those corners or get other rocker arms which are not wide and square at the pushrod end of the arm.

You must be registered for see images attach
 
Last edited:

bucket

Super Moderator
Staff member
Super Moderator
Joined
Aug 3, 2010
Posts
30,439
Reaction score
28,345
Location
Usually not in Ohio
First Name
Andy
Truck Year
'77, '78, '79, '84, '88
Truck Model
K5 thru K30
Engine Size
350-454
The valve cover clearance issue, is that with or without the gasket installed?

Is it a side to side type alignment issue?
 

Ronno6

Full Access Member
Joined
May 14, 2018
Posts
438
Reaction score
126
Location
South Mississippi
First Name
Ron
Truck Year
1984
Truck Model
C10
Engine Size
355
The valve cover clearance issue, is that with or without the gasket installed?

Is it a side to side type alignment issue?

Gaskets not yet installed.
The side to side misalignment causes the cant in the rear edges of the rocker arms, causing
some corners to come closer to the rocker arms.
The misalignment cannot be eliminated due to the widening dimensions from the guide plats to the valve stems.
It is just the way it is.....
 

bucket

Super Moderator
Staff member
Super Moderator
Joined
Aug 3, 2010
Posts
30,439
Reaction score
28,345
Location
Usually not in Ohio
First Name
Andy
Truck Year
'77, '78, '79, '84, '88
Truck Model
K5 thru K30
Engine Size
350-454
Yeah, I was just wondering if it was side-side misalignment. That can be fixed with adjustable guideplates. But adjustment the other way is impossible without adjusting the pushrod length.
 

bucket

Super Moderator
Staff member
Super Moderator
Joined
Aug 3, 2010
Posts
30,439
Reaction score
28,345
Location
Usually not in Ohio
First Name
Andy
Truck Year
'77, '78, '79, '84, '88
Truck Model
K5 thru K30
Engine Size
350-454
Just how bad is the misalignment?
 

Ronno6

Full Access Member
Joined
May 14, 2018
Posts
438
Reaction score
126
Location
South Mississippi
First Name
Ron
Truck Year
1984
Truck Model
C10
Engine Size
355
Yeah, I was just wondering if it was side-side misalignment. That can be fixed with adjustable guideplates. But adjustment the other way is impossible without adjusting the pushrod length.

I have ordered a set of Comp Cams adjustable guide plates.
That is not going to completely eliminate the situation, but may help.
They were the lesser of two evils, cost-wise.
At least if the clearance is not sufficient, I will not have to purchase self aligning rockers
should I opt to change the Scorpions.
 

Ronno6

Full Access Member
Joined
May 14, 2018
Posts
438
Reaction score
126
Location
South Mississippi
First Name
Ron
Truck Year
1984
Truck Model
C10
Engine Size
355
You must be registered for see images attach
Just how bad is the misalignment?
Here is a pic I borroowed fromanother website. It is representative of mine:


Thew dimensions I gave show a .300 wider spacing at the valve stems than at the guide plates,
so it is a bit of a big deal.
I have read that aftermarket heads reposition the intake ports/valves..

Quoted from the Jegs catalog"
"These Comp Cams Adjustable Guide Plates are made to minimize modifications associated with high performance factory aftermarket aluminum or cast iron cylinder heads where the intake ports have been relocated from their original factory position." (except for 1 spelling correction....)
 
Last edited:

bucket

Super Moderator
Staff member
Super Moderator
Joined
Aug 3, 2010
Posts
30,439
Reaction score
28,345
Location
Usually not in Ohio
First Name
Andy
Truck Year
'77, '78, '79, '84, '88
Truck Model
K5 thru K30
Engine Size
350-454
It's for intake runner clearance. As long as the rocker tips are over the valve stems, it doesn't much matter if the rockers are parallel to each other.
 

Honky Kong jr

Super Sarcastic Man
Joined
Jun 14, 2016
Posts
14,968
Reaction score
9,828
Location
Denver,PA
First Name
J-me
Truck Year
87
Truck Model
V10
Engine Size
Lil BB 407
I had Scorpions on my vortec heads and they fit under stock center bolt valve covers. I just put them on my big block and had to get tall valve covers. Also if you run valve covers with droppers it will break them off when you crank it over.....ask me how I know lol
 
Last edited:

Ronno6

Full Access Member
Joined
May 14, 2018
Posts
438
Reaction score
126
Location
South Mississippi
First Name
Ron
Truck Year
1984
Truck Model
C10
Engine Size
355
It's for intake runner clearance. As long as the rocker tips are over the valve stems, it doesn't much matter if the rockers are parallel to each other.

Yessir. I understand that. It has to be that way, no question. Only problem is that the tips of the rockers closest to the intake are coming dangerously close to the inside if the valve covers, and will hit if I do not move the covers up as far as they will go. I may even have to slot the valve cover holes a tad to be able to move up further........
 

Ronno6

Full Access Member
Joined
May 14, 2018
Posts
438
Reaction score
126
Location
South Mississippi
First Name
Ron
Truck Year
1984
Truck Model
C10
Engine Size
355
I had Scorpions on my vortex heads and they fit under stock center bolt valve covers. I just put them on my big block and had to get tall valve covers. Also if you run valve covers with droppers it will break them off when you crank it over.....ask me how I know lol

Some models of Scorpion rockers are narrower than others............
 

82sbshortbed

Fuckemall!!
Joined
Mar 1, 2018
Posts
15,828
Reaction score
53,156
Location
SE Texas
First Name
Doug
Truck Year
1982, 1984
Truck Model
1500 shortbed, 1500 longbed
Engine Size
454, 305
Tall valve covers wouldn't solve your valve cover issue? I know it does nothing for your side to side issue but, at least rockers wouldn't hit your covers. They're pretty cheap. I've got a set on mine.
 

Latest posts

Forum statistics

Threads
44,163
Posts
950,648
Members
36,276
Latest member
2manysquares2care
Top