Phoenix440
Well-Known Member
Slowly getting the top end sorted on a 440 that had a load of issues.
Im fairly new to the hobby and am realising how much there is to know.
I really appreciate the help from the members on here, have learnt a lot, but have a long way to go.
I have a question regarding pushrods removed from the motor.
The lengths vary by up to 0034"on one, with quite a few between .0010 and 0020" shorter than the longest.
The longest rods are pretty close to standard which I believe is .9315".
After watching UTGs video on Youtube: " the tuning issue you never knew you had" I have spent some time attempting to match pushrods to valve heights.
realised I should check for straightness before going any further.
After measuring on a sheet of glass with feeler gauge, I measured some rods weren't straight. Some were out by .004 or .005".
I ended up buying some stock Mellings replacements.
After measuring on a sheet of glass I noticed some of the Mellings pushrods also had a gap of up to .004" and .005"from the glass.
They arnt as bad as a few of the og but I would have expected them to be straighter.
The mellings appear to have a gap of up to .005" when i measure to the glass unless my measuring is out.
Does anyone know what kind of factory tolerance there would have been if there was one orawhat is an acceptable amount of run out on pushrods?
If my measuring is right the run-out on the worst of the Mellings is 2x .005" , so 010".
I have read on some other non mopar forums that .003" run-out would be acceptable even on new pushrods but these appear outside that.
Eventually I want to upgrade to adjustable rockers, so will need new pushrods again most likely, but just wanting to make this the best it can be for now.
Motor has a 480 " lift cam, matched valve springs.
Thanks in advance.
Im fairly new to the hobby and am realising how much there is to know.
I really appreciate the help from the members on here, have learnt a lot, but have a long way to go.
I have a question regarding pushrods removed from the motor.
The lengths vary by up to 0034"on one, with quite a few between .0010 and 0020" shorter than the longest.
The longest rods are pretty close to standard which I believe is .9315".
After watching UTGs video on Youtube: " the tuning issue you never knew you had" I have spent some time attempting to match pushrods to valve heights.
realised I should check for straightness before going any further.
After measuring on a sheet of glass with feeler gauge, I measured some rods weren't straight. Some were out by .004 or .005".
I ended up buying some stock Mellings replacements.
After measuring on a sheet of glass I noticed some of the Mellings pushrods also had a gap of up to .004" and .005"from the glass.
They arnt as bad as a few of the og but I would have expected them to be straighter.
The mellings appear to have a gap of up to .005" when i measure to the glass unless my measuring is out.
Does anyone know what kind of factory tolerance there would have been if there was one orawhat is an acceptable amount of run out on pushrods?
If my measuring is right the run-out on the worst of the Mellings is 2x .005" , so 010".
I have read on some other non mopar forums that .003" run-out would be acceptable even on new pushrods but these appear outside that.
Eventually I want to upgrade to adjustable rockers, so will need new pushrods again most likely, but just wanting to make this the best it can be for now.
Motor has a 480 " lift cam, matched valve springs.
Thanks in advance.
