7/16 poly lock issue
#1
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Joined: Feb 2004
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From: MT. JULIET, TN.
Helping a friend swap to aluminum heads on his 500EFIs and had to order longer pushrods. Now the poly locs seem too short, it almost contacts the rocker body and most of the locking nut is hanging out. These are 1.125 long I believe. Do they make longer ones or can I use the stud girdle type. The roller tips are dead center on the valve tip not sure what I'm missing...Been a few years since i've dove in these things
#2
Lots of different sizes https://www.summitracing.com/search/...r%3A7-16-20-in
Is it possible that the rocker studs are too long?? That would cause the lock to stick out as well.
Is it possible that the rocker studs are too long?? That would cause the lock to stick out as well.
#4
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Joined: Sep 2009
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From: Lake Winnipesaukee, NH
I think it's the other way. If the set screws are sticking out the and locks are way down into the rockers - the heads would need longer studs to get the locks raised.which will lower the set screws. Or do I have it bassackwards?
#6
Backwards. Sounds like he needs about a 0.2 shorter stud or 0.2 longer rocker nut. Which one depends on how much of the rocker nut threads are in contact with the stud threads.
#7
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Joined: Jul 2004
Posts: 11,332
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From: chicago
Helping a friend swap to aluminum heads on his 500EFIs and had to order longer pushrods. Now the poly locs seem too short, it almost contacts the rocker body and most of the locking nut is hanging out. These are 1.125 long I believe. Do they make longer ones or can I use the stud girdle type. The roller tips are dead center on the valve tip not sure what I'm missing...Been a few years since i've dove in these things
Theres many ways to do this, but without getting too deep, put your checking springs on with adjustable pushrod, and keep lengthening the rod watching the pattern get smaller. Eventually, you'll find it start moving towards the outside of the valve stem. This varies with different head brands, valve lengths, rocker brand, and so on. Or you can do it this way, like in the video.







