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Discussion Starter #1
Hey all,

Besides my S-10 I have another engine project going together and I have a question. This engine is a flat top, stock head, budget type rebuild for a truck I am building to sell. I needed a new set of rockers for the engine and found a set on ebay. They were brand new take offs from a Z34 crate engine I believe. I did not realize they were self aligning untill they showed up. Question is, will they work okay on old style SBC heads. I put them on and there are not any binding issues and it looks like they should be fine. I just want to know if there is some problem I might be overlooking.

Thanks,

Chris
 

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You'll have to drill out the push rod slots to avoid the possibility of binding. Be sure the valve tips protrude far enough that the rails don't bottom out on the retainer.
 

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Chris,
do you know if these rockers will fit my modified Scoggin-Dickey heads? They require self-aligning rocker arms with 3/8" studs. If they do fit, how much did you pay for yours? Anything good/bad about them? Are they 1.5/1.6/1.7?

I am finalizing my 383 build for my Camaro.

Thanks,
Denis
'67 Camaro RS
 

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jimfulco said:
You'll have to drill out the push rod slots to avoid the possibility of binding. Be sure the valve tips protrude far enough that the rails don't bottom out on the retainer.

Chris, Email me at [email protected] and I'll mail you a set of stock Vortec type retainers to go with it. They will fit on 1.25" springs.

They will be free. I have them running out my ears.
 

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Discussion Starter #6
Darom, I would suggest getting a quality set of roller rockers if this is anything other than a stock type rebuild. But, if you want to run stamped, I would think that these would work. They are 1.5:1 and are 3/8 studs.

I dont really see any issues with the pushrod slots. The slots actually limit side play more than the rockers. Has anyone actually done this before that can say yea or nea.

Chris
 

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Tried to Email You This

Chris,

if you have that much valve lift, I would machine the heads to accomodate more lift. I use a cutter that cuts down the overall diameter of the guide boss, so I can use a spring with a damper on it. I then machine it down with a special cutter that I can reduce the height of the valve guide by about .150" and it also re-cuts the O.D. so a .500" positive seal will fit it. If you take it to a machine shop, make sure that you check the springs that you are going to use, and verify that they will slip over the existing guide boss. If it does, you only need to cut it down, and re-establish your seal area.
 

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Discussion Starter #8
Re: Tried to Email You This

NAIRB said:
Chris,

if you have that much valve lift, I would machine the heads to accomodate more lift. I use a cutter that cuts down the overall diameter of the guide boss, so I can use a spring with a damper on it. I then machine it down with a special cutter that I can reduce the height of the valve guide by about .150" and it also re-cuts the O.D. so a .500" positive seal will fit it. If you take it to a machine shop, make sure that you check the springs that you are going to use, and verify that they will slip over the existing guide boss. If it does, you only need to cut it down, and re-establish your seal area.
Okay, thanks. I will take a better look, but I have never had an issue with .450 range cams and clearance. I thought that on standard SBC heads, a spring upgrade is all that is required for up to around .500 lift. Are you saying that with the vortec retainers I will need to do this? If so, I think that it would be easier to just get standard rockers. I am not looking to spend any money on the heads.

I guess I should have prefaced this by saying that I would rather get another set of rockers than change the heads. I only paid $15 for the self aligning ones.

Chris
 

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Fords use to run similar rockers on their motors from the late 60's to the late 70's. They were called rail rockers and they had a tendecy to chew up the valve tips. As the valve tips wore down closer to the retainer the rails would push against the retainer, pop out the keeper and drop a valve. They also didn't reccomend any higher lift than stock cams with these rockers. Chevy or Ford I wouldn't use any self aligning rocker for anything over stock.
 

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Chris,


I was under the assumption that you were using Vortec style heads. If you are not, don't worry about machining the guides. If they are Vortec heads, you should machine the guides.


Brian
 

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Discussion Starter #11
NAIRB said:
Chris,


I was under the assumption that you were using Vortec style heads. If you are not, don't worry about machining the guides. If they are Vortec heads, you should machine the guides.


Brian
Nope these are old 882 smoggers off of a 70's vette.

Chris
 

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I'll send you the retainers on Monday Chris.


I'll say a prayer for your father-in-law too.

My father in law just had hip replacement surgery on Friday, and he is struggling with it.



Brian

Oh, and by the way, if you are using self-aligning rockers, you will want to lay the heads in a drill press, and drill out the existing push rod slots to a 7/16" size. Use a high drill speed when you are doing it. This doesn't need to be a high precision job, as long as you get them opened up.
 

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Discussion Starter #13
Thanks Brian.....for both. Let me know shipping cost and I will send paypal or something. I appreciate it.

Chris
 

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The old style pushrod slot holes are similar to guidleplates. They will hold the pushrod so that the rocker stays centered over the valve tip. When you use self aligning rocker arms with the old style pushrod slots, there is a potential for binding. This is because you have two points trying to locate the pushrod.
 
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