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Self Aligning vs. Non Self Aligning Whats the diff??

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Old Jun 23, 2004 | 12:26 PM
  #1  
tanager11's Avatar
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From: Brampton
Car: 91 Z28 Vert
Engine: 305
Transmission: TKO
Axle/Gears: 3.55 10-bolt
Self Aligning vs. Non Self Aligning Whats the diff??

I know I have asked this before....but what is the difference between the 187 swirlport heads and the 416 heads in terms of using Self aligning vs. Non-Self aligning rocker arms.

I mean everything looks the same between the two.....I dont see why there needs to be a difference/some modification between the two types of heads to allow them to use either/or???

It "looks" like I can just take my Self aligning arms and toss them on my 416....everything looks the same...am I missing something??

Help?

D
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Old Jun 23, 2004 | 03:28 PM
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From: clinton,tn
Well the differance is small and hard to pick up if you don't know where to look. The pushrod holes in the 416's are the guides for the pushrods and are oval in shape. The pushrod holes in the 187's are round and the guided rockers keep the pushrods in line, this is true for all sbc roller motors. You can do either if you want to use the 416 heads, use the non guided rocker and don't mod the heads or drill the pushrod holes out to the same size as the 187's and use the self guided rockers. Do not by any means use the unmodded 416's and the self guided rockers together unless you want bent pushrods.

Steve
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Old Jun 23, 2004 | 03:37 PM
  #3  
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From: Moorestown, NJ
Car: 88 Camaro SC
Engine: SFI'd 350
Transmission: TKO 500
Axle/Gears: 9-bolt w/ 3.23's
My '88 LO3 came like that. Had guide slots and SA rockers from the factory. Definatly easy to see where the pushrods have beed grinding against the slots due to each wanting to alighn just a little bit different.
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Old Jun 23, 2004 | 06:22 PM
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From: Glen Allen, VA
I personally feel that SA is better. You'll have less friction loss from no pushrods rubbing on the guide plates.
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Old May 3, 2011 | 03:27 AM
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From: Grenade - France - Europe
Car: Buick RMW 92
Engine: L05 5.7L V8
Transmission: 4L60
Axle/Gears: 2.73
Re: Self Aligning vs. Non Self Aligning Whats the diff??

Digging in the grave yard ... sorry.

I have same question with a L05 engine, casting number 14102193
It has got no pushrod aligning plate of course, only tight holes from casting.

I want to buy narrow body full roller rockers but I still cannot understand how the Self Aligning feature works ...

Then I can't figure out what to order !!!!! If someone could explain a bit more !?
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Old May 3, 2011 | 04:17 AM
  #6  
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From: West-Central
Car: 91 Trans am
Engine: built 360 TBI
Transmission: built 700r4
Axle/Gears: 10bolt/3.23
Re: Self Aligning vs. Non Self Aligning Whats the diff??

187 and 193 castings have guide slots and SA rockers from the factory, I would go with SA rockers.

I found some posts of people using these type heads without SA rockers, not that I reccomend it.

Pics and more https://www.thirdgen.org/forums/tbi/...ers-stock.html
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Old May 3, 2011 | 12:10 PM
  #7  
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From: Pacific NW
Car: 89 K3500 Fleetside
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Transmission: TH400
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Re: Self Aligning vs. Non Self Aligning Whats the diff??

Originally Posted by Jabpir8
I want to buy narrow body full roller rockers but I still cannot understand how the Self Aligning feature works ...
someone could explain a bit more !?
At the valve stem end of the rocker, stamped rockers have small protruding bulges that keep the rocker aligned with the valvestem, with roller tip rockers small washers at the ends of the tip roller serve the purpose.

Neither does anything to assist with controlling pushrod deflection.
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Old May 3, 2011 | 01:27 PM
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From: Grenade - France - Europe
Car: Buick RMW 92
Engine: L05 5.7L V8
Transmission: 4L60
Axle/Gears: 2.73
Re: Self Aligning vs. Non Self Aligning Whats the diff??

Hello Thomas1976 !!

And again for the heads ! (free donation ... my car loves them already !!!)

Reason why I ask about SA Rockers and non SA Rockers is because those have a mix of SA and non SA stamped rockers. let's say on exhaust valves they are all SA and on Intake stems they are all non SA.
Dunno why the machine shop did that !!!
But then could not figure out which model to buy !

I guess non SA will be OK because the pushrod guide holes are quite tight and the posts in the links often explain that guides + SA rockers can cause geometry mismatch (can't figure out why but ...)

so I will be conservative and will get non Self Aligning full roller rockers.
STATE OF THE ART
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Old May 3, 2011 | 02:41 PM
  #9  
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From: West-Central
Car: 91 Trans am
Engine: built 360 TBI
Transmission: built 700r4
Axle/Gears: 10bolt/3.23
Re: Self Aligning vs. Non Self Aligning Whats the diff??



Conservative would be with SA rockers, that is how they came from the factory.

The guys who did the rebuilt in the USA just used what was laying around.

If you feel like using guide plates and screw in rocker studs http://www.maxchevy.com/tech/2007/ii_12-stud-1.html
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