Rocker Arm Question

[Fresh Air Inspector]

Hello All,

It has been awhile, lots of projects competing for my attention. Currently I'm working on assembling my 1988 318LA engine, this is a roller cam version but NOT a Magnum.

The engine has a Howard's cam (I - 220 degrees, 0.475 valve lift, E - 225 degrees, 0.500 valve lift, both @ 0.50, LSA 112 degrees), Hughes Engines roller lifters (HUG 5006), and Hughes Engines dual valve springs (HUG 1110P, coil w/beehive damper; 120 lb. closed, 300 lb. open). Although Howards recommended 140/145 lb. closed, 350/380 lb. open.

I'm struggling with what to do with the pushrods, rocker arms, rocker shaft and rocker shaft bolts. I don't believe these components will handle the valve spring load, especially the stock pushrods (6.777" length, 5/16" diameter, ?? wall thickness).

So, any feedback from those of you that have been there before. Looking forward to the feedback.

 

[Duke5A]

Don't use the factory rocker gear and change those springs. 50lbs to 80lbs is a hell of a difference in open pressure and you're going to risk valve float. The factory roller cam only ran to 4500 and this one will probably run to 5500.

 

[7177rr]

I’ve been running the factory rockers and pushrods on a couple 360s. Factory set up hydraulic rollers with a comp cams 538, 541 224/230@ .050. Not sure of spring pressure anymore. One has aluminum heads one cast iron. Both see 6000 at times and have been together for over 6 years. I may be pushing it but it works