EQ Magnum head max lift?

[Jonnylightening]

Hey guys have a few questions. First off im building a 360 magnum for my Aspen. Im going to be throwing on my set of EQ heads I had on my LA318. I called Racer Brown about a roller hyd. cam, hes a super nice guy. Upon talking to him he was asking about the heads. One of his questions is if the EQ heads will handle a .544 lift cam or what exactly is the max they can handle without machine work? Im using currently the PRW 1.6 roller tip rockers with hughes 1110 springs, but want to go with Hughes shaft mount conversion rockers. Which that brings me to his other question. Will the rocker hit the retainers at .544 lift? Does anyone know or can anyone tell me how to find out? My heads are currently off and the one head is completely unassembled. Any and all help is appreciated. Thank you!

 

[Bobzilla]

I never measured my EQ heads for max lift, but if I understand correctly the basic guide height is very close to stock Chrysler Magnum castings, so that .544" lift is getting close to max lift dictated by the retainer to guide clearance. Your safest option is to measure your heads since you have one apart anyway. Leave the spring out or use a light checking spring if you have one. Make sure a valve stem seal is in place. Then just measure how much the valve moves from open and touching the seal lightly to fully closed. Now subtract a safe amount for retainer to guide clearance and that will be your available max valve lift of the head. You'll need to double check the actual valve spring for coil bind while assembled too, but this is how you can easily get the real numbers for your heads and valve parts.
Hopefully that helps, because it feels like I may have been rambling on.

 

[Jonnylightening]

I never measured my EQ heads for max lift, but if I understand correctly the basic guide height is very close to stock Chrysler Magnum castings, so that .544" lift is getting close to max lift dictated by the retainer to guide clearance. Your safest option is to measure your heads since you have one apart anyway. Leave the spring out or use a light checking spring if you have one. Make sure a valve stem seal is in place. Then just measure how much the valve moves from open and touching the seal lightly to fully closed. Now subtract a safe amount for retainer to guide clearance and that will be your available max valve lift of the head. You'll need to double check the actual valve spring for coil bind while assembled too, but this is how you can easily get the real numbers for your heads and valve parts.
Hopefully that helps, because it feels like I may have been rambling on.

Thank you. I had done that and gave my specs to Racer Brown...hes a super nice helpful guy

 

[mchartier105]

I'm running a comp 268 xtreme energy solid cam in a 98 318 Magnum block with factory replacement heads, Hughes 1110 spring kit with retainers and 1.65 rocker arms for .539 lift (.551-0.012 for lash) and it's tight but I've been running it on the street for about a month now and no clearance issues.

 

[Bobzilla]

I'm running a comp 268 xtreme energy solid cam in a 98 318 Magnum block with factory replacement heads, Hughes 1110 spring kit with retainers and 1.65 rocker arms for .539 lift (.551-0.012 for lash) and it's tight but I've been running it on the street for about a month now and no clearance issues.

Did you measure the retainer-to-guide clearance? Curious what you had on that combination.
Also, what brand of factory replacement heads? Mopar Performance Chrysler castings or something else?

 

[mchartier105]

Did you measure the retainer-to-guide clearance? Curious what you had on that combination.
Also, what brand of factory replacement heads? Mopar Performance Chrysler castings or something else?

I haven't measured but I can if everybody is interested, and they're super cheap replacement castings from rockauto, I believe CCCN or something like that, I think they were $250 CAD each for a bare head