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I was just trying to get my pushrod size today and had some weird things happen.
The heads are c9ve (same as dove's), 1.73 harland sharp roller rockers,ARP 1.75 chev big block studs, comp 3/8 stud mounted guide plates, 10 new valves- stock size, head has been machined but i dont know know how much, com 282s cam - .57 lift and 282 duration both intake and exhaust, comp solid lifters,comp double valve springs, comp doulble roller timing chain set, the heads were machined to fit the valve springs and seals, i gave them a mild port job and poilish- mostly to get rid of the exh hump.

Ok, now thats all sayed and done :)

I installed the guide plates and studs. put the roller rockers on and started adjusting the polly locks until the roller was just slightly to the intake side of the vlave stem. I then installed the adjustable pushrod and adjusted the length, locked everything and turned the engine over then checked the partern on the valve tip. The intake side went ok but I was a little concerned with only having aprox 1/16 of adjustment until the rocker bottoms out on the stud. Next i set up the exhaust side and used the pushrod adjusted to the same size as the intake- it was too long and i found the pushrod hits the guide plate then gets jammed. i ground out the exhaust side guide plate so the pushrod no the exhaust side longer gets jammed against it. Then continued and adjsuted the pushrod for the exhaust side. Every thing seems ok but I did notive the pushrod is on much more of and angle to the pocket on the rocker. i did transfer the pushrod back to the intake side and recheck the pattern - it looks ok, its just slightly to the exhaust side- very slight.

My major concern is the anlge of the rockers. As far as I can see it all comes down to the length of the roller side of the rockers, its too long. if it were shorter I would be able to tighten the rockers down less without loosing centered valve tip pattern. this would fix the pushrod/pocket angle. It would also fix the pushrod hitting guide problem. It would fix the rocker to stud clearance also.
Has anybody else ran into these problems before? Please help.

Sorry for such a long post but i wanted to give you all the info you needed.

Thanks
Dave
 

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I have the exact same problem. I'm just running a solid roller with dove heads.
The shortest pushrod I could go with was 8.450 and that's only so it wouldn't bottom on the rocker stud. Also like you said when the valve is closed the rocker and pushrod just start to bind in the ball and socket. So I thought I would go with these pushrods from Crower, 71845R. They have a 210deg radius on the top so the rocker and pushrod won't bind, the only problem with this is that their tapered towards the top, now when valve is closed there is a lot of play from side to side, when the valve starts to open then it centers the rocker. The only solution to fixing this that I could think of was to buy flat guide plates, but I can't seem to find anybody who has them, only raised.
 

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Most roller rockers are not designed for Ford canted valve heads they are for BBC's. The geometry is different. To make things worse the Ford heads valve geometry is different between the exhaust and intake. This realy requires different rocker arms on the intake and differently configured rockers on the exhaust.
If you measure the lift at the valve and compair it to the cam spec's they will most always be less than advertised no mater what you do. Sometimes the pushrod holes in the heads have to be ground out. A cam with more lift might be needed to acheave the lift wanted.
If you set the cam at half lift and the rocker stud is not centered in the rocker slot geometry is wacked. Many canted valve Fords end up with the stud centered at valve closed position and as the valve opens the slot moves towards the stud.
One fix might be to go with 1.8 rockers or find proper geometry ones. Last I knew someone in FLA was making seperate geometry rockers for intake and exhaust for Fords and were around 500 a set back in the earkly 90s.

Also have had some geometry issuses using checker springs instead of the actual springs to be used.
 

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"the rocker bottoms out on the stud"
........................................................
The rocker hits the hex of the stud ? If so, have you mill down the ht. of the stud boss pad of the head?
 

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"the rocker bottoms out on the stud"
........................................................
The rocker hits the hex of the stud ? If so, have you mill down the ht. of the stud boss pad of the head?
If you machine the boss down, won't you run into more of a geometry problem with the ball cup binding?
The push rods I have are the 8.450 w/210 radius which solved the problem of the binding but now because of the taper at the top of the push rod it allows more play side to side on the valve tip when closed. When it starts to open the valve it has to force the rocker to center on the valve tip because of the raised guide plate. I didn't think this would be very good for the roller tip.

I don't mean to hi jack his thread, just thought it would also help Dave out too.

Lance
 

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I don't think it was a good idea to grind the guideplate... might have been a better idea to split it in the middle, align it to the best location, and tack weld it back together. I believe by grinding on it, you have made a rough spot to gouge a pushrod.

Tom
 

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If you machine the boss down, won't you run into more of a geometry problem with the ball cup binding?
The push rods I have are the 8.450 w/210 radius which solved the problem of the binding but now because of the taper at the top of the push rod it allows more play side to side on the valve tip when closed. When it starts to open the valve it has to force the rocker to center on the valve tip because of the raised guide plate. I didn't think this would be very good for the roller tip.

I don't mean to hi jack his thread, just thought it would also help Dave out too.

Lance
The angle will still be the same......no geo. issues.
 

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Most roller rockers are not designed for Ford canted valve heads they are for BBC's. The geometry is different. To make things worse the Ford heads valve geometry is different between the exhaust and intake. This realy requires different rocker arms on the intake and differently configured rockers on the exhaust.
If you measure the lift at the valve and compair it to the cam spec's they will most always be less than advertised no mater what you do. Sometimes the pushrod holes in the heads have to be ground out. A cam with more lift might be needed to acheave the lift wanted.
If you set the cam at half lift and the rocker stud is not centered in the rocker slot geometry is wacked. Many canted valve Fords end up with the stud centered at valve closed position and as the valve opens the slot moves towards the stud.
One fix might be to go with 1.8 rockers or find proper geometry ones. Last I knew someone in FLA was making seperate geometry rockers for intake and exhaust for Fords and were around 500 a set back in the earkly 90s.

Also have had some geometry issuses using checker springs instead of the actual springs to be used.
He said he is using Harland Sharp 1.73 rockers. Harland is one of the companies that make Ford specific rockers. So unless the OP ordered Chevy rockers, there shouldn't be a problem with the geometry.
 

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He said he is using Harland Sharp 1.73 rockers. Harland is one of the companies that make Ford specific rockers. So unless the OP ordered Chevy rockers, there shouldn't be a problem with the geometry.

Havent used any Harlands on a canted valve Ford. There is still the issue are they the correct geometry for the intake or exhaust?
 

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STOP using the valve tip wipe pattern as your MAJOR criteria for getting the valve train geometry correct or, you'll NEVER get it right.

IF those C9VE heads have NEVER had the stud pedestals milled then they need to be cut about .190" / .230" to be correct.
 

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I had this exact same issue 4 years ago and gave up!!! My build, Scott's first set of ported DOVEs, comp solid roller, Harland Sharp roller rockers, Comp stepped guide plates. The exhaust side would bind in the guide plate so I ground a little meat out of the guide plate stud hole so I could rotate it away from the push rod. It worked in theory but have had nothing but problems with the motor since. Rockers walking off. Loose studs. A dropped valve!!!

So whats the fix? Milling the pedestals down? I used the swipe method to determine pr length and came up with 8.4. Randy whats the correct method? Do I need to switch to different rockers on the exhaust side? My HS rockers are the Ford part but I've heard people have issues with them.

I'm not trying to thread jack but this is the first time in 4 years someone else has had the same problem I have!!
 

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I had this exact same issue 4 years ago and gave up!!! My build, Scott's first set of ported DOVEs, comp solid roller, Harland Sharp roller rockers, Comp stepped guide plates. The exhaust side would bind in the guide plate so I ground a little meat out of the guide plate stud hole so I could rotate it away from the push rod. It worked in theory but have had nothing but problems with the motor since. Rockers walking off. Loose studs. A dropped valve!!!

So whats the fix? Milling the pedestals down? I used the swipe method to determine pr length and came up with 8.4. Randy whats the correct method? Do I need to switch to different rockers on the exhaust side? My HS rockers are the Ford part but I've heard people have issues with them.

I'm not trying to thread jack but this is the first time in 4 years someone else has had the same problem I have!!
Sometimes you can get away with NOT milling the pedestals and it will work but, it is NOT correct.
Harland Sharp has TWO part numbers for a big block Ford rocker arm. One will NEVER have a wipe pattern more than halfway toward the intake flange side of the valve tip when the rest of the geometry is correct. However, that rocker arm will exhibit the best valve and guide wear scenario.
Geometry on the PUSHROD side of a ROLLER rocker arm is much more important to be near correct than ANY other single place. The pushrod should be perpendicular to the rocker arm cup recepticle at 1/2 to 3/4 valve lift. Some compromise is usually necessary to have all the geometries close to right.

EDIT: Everything in the industry seems to revolve around the small block Chevy and for some reason people tend to think this will be correct for every engine in the marketplace.
 

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The best I can tell they have a 1.73 and a 1.8 rocker. I know 1.73 is factory ratio and thats what I'm running so why am I having this binding issue? I'm still very confused
 

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The best I can tell they have a 1.73 and a 1.8 rocker. I know 1.73 is factory ratio and thats what I'm running so why am I having this binding issue? I'm still very confused
You're having problems because you are treating your engine as if it was a small block Chevrolet ... when the geometry is close to right and the pedestals have been milled correctly there are no problems.

They may have 1.73's and 1.8's in BOTH part numbers; I believe they are S4073 and S4005.
EDIT: these part numbers are from memory so they may not be exactly correct.
 

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The best I can tell they have a 1.73 and a 1.8 rocker. I know 1.73 is factory ratio and thats what I'm running so why am I having this binding issue? I'm still very confused
A lot more than just the ratio to consider. These are not my pics. Thanks to the guy that did this, who ever you are!
 

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I took some pic's of the intake and exhaust valves open and closed.
Does the geometry look right to you guy's?
Because I did the same thing as torinoman did, grinding a little from the guide plate so the pushrod wouldn't bind up against it when the valve closed.
This is my first BB build so I just want to make sure it's right.:)

Thanks for the help.
 

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