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Discussion Starter #1
I finally took a few pics of what Im dealing with,the heads are afr 190s and Im wondering if this is a problem or not. The roller rockers dont sit strait on the head, they seem to be "crow footed". this doesnt look right to me but the rollers lign up fine with the stem of the valve. I got right under three thousands taken off the bottom of the head to bump up the compression and Im wondering if thats why. I didnt think that should make a difference but Ive been thinking about it for a little while now and Im stumped. thanks Ryan

http://i60.photobucket.com/albums/h33/383rrs/DSC00193.jpg
http://i60.photobucket.com/albums/h33/383rrs/DSC00195.jpg

oh and as you can see in the pic I cut a few of the guide plates and adjusted them slightly and got the rockers as strait as I could while still making full contact with the valve stem.
 

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just a thought but could these heads have been designed for offset rockers?:confused:
 

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Discussion Starter #3
I dont think so but I cant be positive, I called AFR hoping for a easy fix or simple explanation but I was a little disappointed. the guy I talked to kept saying the heads dont come new with the valve guides adjusted which I know and I checked them over plenty of times. he told me that afr offsets the valves slightly for better flow through the head and they might look crow footed but it seemed like an answer just to get me out of his hair. ha
 

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Discussion Starter #5
I colored the stem with a felt tip and and got a mark that started right at the center and went a hair towards the inside of the valve stem. Ive tried to do as much reading as i could about pushrod lenth and Im thinking its ok. Im worried about the side loading on the pushrods against the guide plates and rockers. I almost wish the rollers didnt line up with the valve stems so well so I would know theres a definit problem. Ive never really heard anything about the rockers HAVING to be perpendicular to the head but I would think that would have be the condition for best geometry:eek:
 

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I'm going to go out on a limb and say they are OK. Aftermarket heads often move the pushrod over from true center to straighten the port for better flow.
At some point offset rockers are required but those are probably OK as long as you pushrod length is correct and the guide plates are adjusted.
 

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Paul Wright said:
I'm going to go out on a limb and say they are OK. Aftermarket heads often move the pushrod over from true center to straighten the port for better flow.
At some point offset rockers are required but those are probably OK as long as you pushrod length is correct and the guide plates are adjusted.
I have a set of new Dart Platinums that I'll be putting on in a few days and have heard they do the same thing in order to get better flow. I have seen pictures taken looking over the lifter valley towards the intake of the heads showing the pushrods going off at quite angle. Dart recommends to push the guide plates over to the intake side as far as posible.

Is it normal to have the push rods rubbing on the guide plate?
 

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Discussion Starter #8
Thanks pual, Im glad youve heard of relocating the valves slightly, it gives a little more credibility to what the guy down at afr was saying. I wanted to believe him...I really did.lol but you know how you get the "your interupting my lunch break" feeling....anyway, Im going to get them as close as I can and go from there. I know the situation isnt to an extreme but I planning on having a higher rpm motor when im done and the valvetrain is one area I dont want to cut any corners in.
 

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Discussion Starter #9 (Edited by Moderator)
slight wear is normal, and the reason for hardened pushrods but excessive isnt. I would call normal "shiny" spots on the inside of the groove where the pushrod touches. If you have any type of grooves Id start looking things over.
So dart recommends putting them all the way to the intake; thats probably where they lign up the rockers with the valve stems the best I would guess

....thinking about this topic as a whole...man, what wont we do for better flow!! ha
 

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You'll be OK!

I have the same problem with my Ebrock RPM heads. I adjusted the guide plates the best I could, to center the rocker. Haven't had any problems.

You'd think after paying big bucks for a set of heads they'd get it right!
 

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.....I just read over my last post....take out that "will":rolleyes:
I did it for you but just use the "edit" buttom next time ~ pual the mod
maybe more people see this than I thought. after I sat the rockers on and checked alignment it was like poopin' with your pants up...it just didnt make sense. Im thinkin it might work out though
 

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loneagle said:
You'll be OK!

I have the same problem with my Ebrock RPM heads. I adjusted the guide plates the best I could, to center the rocker. Haven't had any problems.

You'd think after paying big bucks for a set of heads they'd get it right!
I'm not sure what you are saying with that last line.
Look at a stock Chevy head and you'll see the port has to make a bend around the pushrod. This inhibits flow. To get more flow from the stock Chevy design they have to move the pushrod over. If they lined up the pushrod and the valve stem you wouldn't get the flow. High performance has trade offs. Misaligned rockers are an example of one.
 

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Discussion Starter #14
I shouldve said decked. for a second I thought that might effect it but considering the correct amount of pushrod lenth change I dont think it would.
 

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ready2run said:
loneagle, did you machine your heads at all?
No machine work done. The block has been decked .020 Used stock length pushrods.

Paul,
If that's the way there designed, then I have no complaints. Just thought it looked strange when I installed my rockers. I understand your point on the runner design. If it makes more power then that's good. :)
 

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I've seen some circle track guys that have adjustable guide plates. Not sue what brand but it helps line the rockers up better.

Carl
 
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