I need a resource for engine component differences!

I'm changing my head on my Duke. I thought I had an 86 head, but the 86 head I bought has different valve heights and the rocker arms from my old head do not fit the new one. Any help?


The valves on the new head are roughly 1/4 inch taller than on the old head but the point where the rocker arm bolts to the head is at the same height. This doesn't allow proper motion for the original rocker arms.

I'm hoping to find rockers and maybe push rods to order that work with it.

Thanks for any advice.

-Michael

I would do the conversion to adjustable rocker arms since you have to replace them any way. I haven't done it yet but I am told it really quiets the motor. It entails buying rocker arms for a 1966 Chevy 4 cylinder and studs for an LS GM engine.

You can put big block chevy roller rockers on a duke...

But you'll also need a bigger valve cover.

quote Originally posted by TopNotch: You can put big block chevy roller rockers on a duke... But you'll also need a bigger valve cover.

I didn't need a bigger valve cover?

Just do the conversion to adjustable rockers you can use your existing valve cover

quote Originally posted by TopNotch: You can put big block chevy roller rockers on a duke... But you'll also need a bigger valve cover.

is there a benefit to doing this other than appearance? Sure does look nice!

quote Originally posted by DLCLK87GT: is there a benefit to doing this other than appearance? Sure does look nice!

Well, the roller rockers + the Accelerated Motion camshaft + the '92 head = better performance. It used to gasp at 4500 RPM. Now it still pulls at 5000 RPM. I'm afraid to go faster than that, though, because, you know... it's a duke.

I notice you have a spacer between the intake and head. For what? And where did you find that valve cover?

P_

The spacer allows the EGR valve to clear the valve cover. The valve cover is the Super Duty 4 (SD4) cover. Still available from some online sellers. Google GM 10031327.

the problem with changing rockers arms is to have the good sets i saw too many times people trying anything and like me ( i speek french ) and i bought a wrong rockers sets take the good oem one or if you want roller rockers take the good sets that have the application for your engine or someone who is a master that you trust to guide you with the rockers for your needs . it is a good idea to buy a valvespring height micrometer i bought one to make sure because older heads will not have the proper height ( machine seat spring pockets special retainer ....... you must have .040 minimum clearance between your retainer and the rocker arm and check the pushrods length for your need with a pushrods length checker tool too to have a good rockers contact point