Rocker arm geometry

I’m building a limited modified the the rocker arms contact point is slightly off the back of the tip of the valve almost like the pushrod is about .250 or so to short. it really pushes on the valve when it starts to open it. The rules say stock rockers and stock length pushrod. The block and head have both been cut And a .045 head gasket. the only way I know to make it better is to grind the contact point on the rocker. I was going to see if anyone else has a better solution.
 
As Brian said try shortening the top of the valve. But if that doesn’t work buy the reformed rocker arms from a speciality engine shop.
 
For some reason I was thinking there was a minimum length on the valve so I didn’t think they could be ground but I looked back at the rules and didn’t see it listed. That will definitely get me closer by cutting the tip but I don’t think it will be enough to get it where it needs to be. I’m going to pull the cam back out and check the base circle it kinda seems like it has been cut smaller than what it should be. Would the reformed rockers change the lift? There is a .307 lift check off of the retainer.
 
Is there a Length check on the push rods ?
something dosent add up , A push rod 1/4 " too long seems excessive .
 
Yeah 5.638-5.656 in the rules.they both measure 5.650 and it seems like the pushrod is to short not to long I’m going to pull it apart and check the cam something seems way off.
 

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It’s a mod1 the base circle is .815 I called dyno and randy said .815 is right but it looks like the lifters are .166 shorter than the billet lifters dyno sells for a animal I don’t have any others to compare it to but that seems like most of the problem at this point.
 
Yeah 5.638-5.656 in the rules.they both measure 5.650 and it seems like the pushrod is to short not to long I’m going to pull it apart and check the cam something seems way off.
Shorter or longer 1/4" is a lot .
Stock animal lifter should be
1 .515-1 .525 "
 
This is interesting, with my all stock lifters, push rods and valves. And mod 1 cam. The poly lock set screw is down inside the poly lock.
 
If max valve lift is your only rule you have some good options to make more power. Call an engine shop who knows what’s going on, they are far and few.
 
Be interesting to know if they are over length valves .
I can't imagine theres been that much milled off the block and head . Now as i say that ; Ido have a head with . 100 milled off so it's possible .
 
This is interesting, with my all stock lifters, push rods and valves. And mod 1 cam. The poly lock set screw is down inside the poly lock.
I had just screwed the nut on by hand to zero lash just to show how bad it was.
3.362 valve length . Minimum.
WKA limited rule , says any lifter .
We use Akra rules at our track. There is no valve length min or max in the rules I see but it does call out a min and max on lifter length 1.526 the lifters in the engine measure 1.359 so someone has either cut them or they are for a different type engine I should have a stock length set maybe Sunday I think that will fix the problem the deck has been cut probably more than it needs to because I had to mill .015 off of a wiseco c piston. And still have .005 pop up. With the Milling of the deck and head that should have helped my problem.
 
hey sir. R those dynocams 36# springs kit. Thats what i got for this 310 cam i purchased from them. My spring kit is green too. But the 4 retainer keepers in my the kit don’t look correct. They r plain in color and r quit big looking. R your retainer‘s black or plain colored. If u have the same spring kit?
 
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hey sir. R those dynocams 36# springs kit. Thats what i got for this 310 cam i purchased from them. My spring kit is green too. But the 4 retainer keepers in my the kit don’t look correct. They r plain in color and r quit big looking. R your retainer‘s black or plain colored. If u have the same spring kit?
Yeah they are dynos 36# the keepers mine are black. Put them around the valve by their self and see if they fit good.
 
I got the lifters today the ones in the engine were .180 shorter than the factory’s. I’m not sure what they were out of I can’t find that length lifter anywhere and they don’t appear to have been cut down but anyway the rockers look good now.
 
Yeah they are dynos 36# the keepers mine are black. Put them around the valve by their self and see if they fit good.
Dyno sent clone split locks by mistake. Plain in color and r for a smaller valve Stem. I got the correct black ones. Thank’s! Fitting all the parts together correctly is part of the challenge.
 
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